During the second world war the British not so famously (it's not like it's something you brag about) spent a lot of money and effort building extremely heavy tanks or assault guns designed to help a spearhead a breach of the Siegfried line. They turned out to be mostly unnecessary due to a combination of factors that can be roughly summed up as "quantity has a quality all its own" and the projects were steadily cancelled as the war in Europe wound down.
It's likely that some of these big unknown problems will similarly evaporate or prove to be easily solved once we actually do stuff like put humans in deep space ad on the moon for serious chunks of time.
It really puts the frustration I have with Musk's constant "we're going to Mars" in context. Yes, a big rocket is necessary prerequisite for Mars. No, it is not the only problem you need to solve.
And also having worked with the reality of human spaceflight operations, we are just not ready yet to send a spacecraft into deep space for months on end. It's easy to throw out blithe statements that we "just need a big spaceship", or we'll use ion drives or some other such tech, but the reality is way more messy than that. We just aren't ready yet and we won't be for some time.
The large rocket adddresses basically all the problems.
Time between resupply? Well, you can just take a bunch of resupply missions with you. Most stuff is packed ahead of time, except fresh veggies and fruits, but deep freezers can keep the nutritional value of those nearly as well as being fresh.
Redundancy/reliability? Bring the spare pool with you instead of keeping it on the surface for resupply flights. Bring two different systems.
Long duration life support? Enough mass allows you to avoid it all together if you like. This still has not sunk in to most of the fairly educated people who opine on this topic. Simple life support systems are VERY reliable, and the advantage of advanced life support systems is they reduce mass. If you don’t need the mass reduction, you don’t need the advanced life support.
Far from medical care? Small crew sizes are a mass constraint. More mass means you can afford large crews with dedicated medical personnel. And the equipment to go allow with it.
Also applies to radiation shielding (mass) and even partial gravity (centrifugal gravity is well known as a replacement but for some inexplicable reason is avoided… and yea, even short arm centrifuge is useful and could be used on the surface… the disorienting effects are actually manageable, and while in space, a tether can be used to enable long arm centrifugal gravity with little Coriolis effect).
Transit times can also be reduced significantly with refueling. 80-120 day transits are feasible, not just the most efficient 150-210 day transits for long stay. The surface of Mars also has significant radiation shielding in spite of the thin atmosphere. The Mars rover Curiosity measures the same radiation equivalent on Mars’s surface as on ISS today. Mars rover Perseverance also demonstrated production of unlimited oxygen from the Martian CO2 atmosphere using electricity. Regolith could also be used to enhance radiation shielding. This is before discussing water mining (and even that can be done without touching regolith, just the air using the WAVAR technique… useful for crew consumption although this method doesn’t scale up to producing enough for propellant very well).
There is no a single hazard or obstacle to a Mars mission that isn’t at least partially mitigated by having a lot more mass capability, ie a big and cheap reusable rocket (capable of landing on Mars and aerobraking).
Well there is the "one-way trip" version which takes out some risk but trades the risk of losing 4 astronauts for the risk of losing 400 or more.
Since it's not plausible that you could bring anything back from Mars that would be worth enough to make colonization practical from the perspective of Earth, Mars colonists would always have to assume that the last rocket that was launched is the last that will arrive. From their point of view, they'd want to be able to manufacture absolutely everything locally as soon as possible.
It's one thing to say "we can make unlimited oxygen from the soil never mind the atmosphere", it's another to find a source of nitrogen or other inert gas that makes it possible to live in an atmosphere that doesn't make everything into a firetrap. It's one thing to spin the kind of science fiction that Gerard K. O'Neill did, but his disciple Eric Drexler realized just how bad the problem of 'advanced manufacturing' is and went off to follow his own El Dorado, writing a fascinating book [1] about a class of systems that 'just don't work' [2]
Not to say that the goal of "a population of 10,000 people being able to make everything that 8,000,000,000 can make" is unattainable, even if we can get it down to an advanced industrial base being supported by 10,000,000 people it would be a game-changer here on Earth. I can see paths there, but it's by no means a bird in the hand.
It would probably be smarter to launch multiple payloads than have everything in one big payload, a fire can take out the primary and redundant supplies for example.
That said, throwing more money and gear against the problem will likely be the way to go. Besides, it doesn't actually have to be done all in one go, if the vision of SpaceX is that of mass production, they can launch a whole chain of Spaceship sized payloads towards Mars years before a human crew is sent that way, giving them supplies and whatnot on the way, in orbit, and on the surface. That'll require a lot of planning and automation though.
This is irrelevant and completely ignores the OP. We've had rockets capable of going to Mars since the 60s. More rockets do not solve the problem. Cheaper rockets do not solve the problem. Please read the article.
We send spacecraft to deep space for decades on end, not just months. Oh, you meant CREWED spacecraft…
We are in fact far more ready for sending crewed missions to Mars than we were to sending crewed missions to the Moon when JFK made his Moon speech. We had only barely launched an astronaut on a suborbital flight at that time! And yet 7 years later…
On the one side, you have a point, but on the other... as the article mentioned, a moon round trip can be done in the span of a week, they can set the craft on a trajectory so that it has a free return even if the thing becomes uncontrollable. Not so for Mars trips, after a few hours they're committed to the trip. The article then mentions everything that can go wrong.
I'm confident that if they tried to launch a Mars mission with current-day technology now, the crew wouldn't make it. Nobody's ever been in space for that long, to start - yet Musk wants to deorbit the ISS, the only viable platform at the moment to even try and simulate a two year space trip.
“Current day technology” is sort of poorly defined because you can make new technology in one day. “Current tech” is a fake constraint, because even preparing for a launch in two years, you’d be developing new technology all along the way.
The annoying thing is that we could’ve been simulating long duration partial gravity using artificial gravity for decades, but NASA has refused to do so. For inexplicable reasons. If I had to guess, it’s due to the microgravity research community fiefdoms who have made a career of microgravity health effects and so don’t like the idea of directly addressing them using artificial gravity as it makes a whole career’s worth of work largely obsolete.
Not if you want it dependable enough to entrust a multi billion dollar project and several people’s lives to it.
People talk about the moon mission like some massive conquest of space, but we needed to get the fuck off the moon much past sunrise or astronauts would have cooked. It was based on extremely limited oxygen supplies and involved significant radiation exposure that was only ok because again we ran away from an extremely inhospitable environment before things went wrong.
Even today the ISS benefits from earths magnetic field, its space light not a true replica of a mars mission.
The "To the Moon" speech was made in 1962 when we had basically no knowledge of space. We'd only sent a man into Low Earth Orbit for the first time a few months prior. 7 years later we'd land a man on the Moon. And we'd repeat this several times over until Nixon effectively cancelled the human space program in 1972. Obviously 7 years is not one day, but I think 1 day was clearly figurative rather than literal.
The biggest problem is that people have really lost the ability to think big. There's always infinite reasons to not do something, and there will never be a perfect time. So at some point you simply have to choose to push forward. Like Kennedy put it:
"We choose to go to the moon. We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others, too."
> The "To the Moon" speech was made in 1962 when we had basically no knowledge of space.
Talk about hyperbole.
The moon mission has been prepared for before that speech took place. It wasn’t just starting from scratch and hitting the moon in 7 years, instead the speech was more public disclosure of a deadline that looked achievable but would hit after his presidency (1960 + 8 being less than before the decade is out: 1970).
The biggest problem is we already did the easy stuff. Playing tag with the moon is unbelievably easier than a permanent moon base or landing on Mars and getting back to earth.
Obviously we'd been wanting to go to the Moon before that speech, but there was no secret technology that we were just being coy about. We still knew nothing, had nothing and were in the process of figuring out what John Glenn's fireflies were during a flight where, if he wasn't such an uncannily good pilot, he probably would have died.
Saying we'd be on the Moon in 7 years was not something that looked achievable except to the most fanatical of enthusiasts. To the average layman it would have sounded no less impossible than me saying we'll have a man on Mars in 7 years from today. And landing on Mars in many ways will be much easier than the Moon. Not only is the terrain broadly more hospitable, but you have an atmosphere to enable aerobraking which simplifies both landing and braking and enables various options (like some sort of parachute staging or backup). The biggest and really only complexity with Mars is its distance. Outside of that it's easy mode.
On the contrary, we can easily get people there alive. What exactly do you think is beyond our capacity to send crew to Mars while still being alive? Crew regularly do year long expeditions on ISS (edited for clarity), with total radiation dose similar to Mars transit (and show no measurable effects of that radiation).
Again, I’m addressing the point “getting them there alive”. Unquestionably, we know how to get crew to Mars alive, and even for the full mission duration, radiation isn’t even in the top 10 of the hazards that could actually kill them during the mission. (It’s a long term hazard, comparable to lung cancer if you’re a cigarette smoker.)
The world record duration still sits at 438-days after 35 years. We limit people below that due to medical issues, suggesting no we don’t know how to safely do multi year space flight.
It’s possible people spending significant time on the surface of mars would recover, but that’s more speculation than proven.
No one has ever done a "years long" expedition to ISS, and the radiation flux in transit to Mars, in particular GCR dose, is much higher than experienced on the space station.
I’m well aware, just mistyped. The total equivalent radiation dose on a fast transit to Mars is less than some ISS expeditions.
Note that the magnetic field only deflects lower energy galactic cosmic rays which have a lower gyro radius than the real whoppers. The magnetic field is less important to overall radiation shielding than the earth’s atmosphere.
No, NASA also didn't think it was possible at the time. There's an informative little paper here. [1] It only gets more informative from the first sentence, "Mathematical risk analysis was used in Apollo, but it gave unacceptably pessimistic results
and was discontinued." By the time of the launch to the Moon NASA's internal estimates were looking at around a 50% chance of success based on Gene Krantz's (mission controller) "Failure is Not an Option" book.
It was a mission they dedicated themselves to, and humans have this way of making things happen when we actually set our minds to tasks. A reality that's often been lost in modern times as we have mostly moved away from pursuing, let alone achieving, great things in the real world. One of the many reasons to get humans on Mars.
You’re confusing specific low odds of success for “didn't think it was possible.”
The Apollo missions got unbelievably lucky in that none catastrophically failed despite multiple close calls. However, if you’re willing to try multiple times the odds any mission being successful is much better than every mission being successful.
IE: Six missions landed on the moon. If they each had independent 50% odds then six heads is a long way from impossible ~1.6%, but at least 1 head is quite likely ~98.4%. I doubt we would have tried for a 6th mission after 5 failures in a row, but the point is definitions of success matter a great deal here.
Similarly failures improve odds of success in the future because you learn from mistakes and success means the system is functional eliminating some risks.
What I'm demonstrating is that we indeed knew basically nothing. There was no secret tech or expectation of success. Mathematical models doomed the entire idea to failure, and all the way up to the day of the launch people who spent years in a bubble of optimism still didn't really expect more than a 50% chance of success.
On that specific launch, which is another way of saying they believed the project had a very good chance of having someone walking on the moon. Failure there wouldn’t even mean people died, just that they didn’t walk on the moon and then safely get back on that mission.
It does not; see the paper cited in my other reply to you. GCR dose is 1.5-2x on Mars compared to ISS.
The mention of "quality factor" here just begs the question. The reason we need research on biological effects of high-Z ion exposure is that it has a different mechanism of damage, not captured by that paradigm.
A significant part of that is because it’s much further from the sun.
A hypothetical 500 day mars mission is ~1 Sv optimistically which is something like 5% fatal cancer risk. A 3 year mission you’re well above that even before considering solar storms etc.
I think many would sign up for a mars mission especially as treatment improves, but there’s only so much wiggle room here.
> We send spacecraft to deep space for decades on end, not just months. Oh, you meant CREWED spacecraft…
The track record for successfully landing on Mars isn't that awesome:
> Historically, counting all missions by all countries, there has been about a 50% success rate at Mars — and the odds of successfully landing on Mars are only about 1 in 3.
That isn't a very useful statistic - all you should really glean from it is that landing on Mars is hard. The US has done it 9 out of the 10 times it tried, so it seems reasonable that it would succeed.
It was done by NASA, who have a culture of triple/ quadriple checking and being very careful about mitigating risk in ways that may seem inefficient to some. I don't see NASA leading the effort to Mars in any meaningful way besides being a conduit for money from the treasury.
> We are in fact far more ready for sending crewed missions to Mars than we were to sending crewed missions to the Moon when JFK made his Moon speech
When JFK made the speech, it was in the middle if the cold war and there was a realistic fear that the "capitalist way if life" could be beaten by command economics of the Soviet Union in cutting edge science and rocketry, justifying the huge amounts invested in the space race. What is the impetus now? We're all about government efficiency in cutting the social-safety nets, scientific research, but we'll carve out a Mars mission "because it's hard"?
No, the biggest hurdle is having astronauts survive the journey (health and successful landing/departure of Mars). It would be over 3 years in space to round trip to Mars with current tech. We haven't had an astronaut in space continuously over ~1 year...the body suffers tremendously in a low gravity environment and you would have to handle SO many side effects and redundancies in life support etc.
Artificial gravity would address those issues. The big rocket (ie mass margin) also addresses life support redundancies (and allows you to use simpler, much more reliable methods like used on short duration spaceflights).
No, the big rocket is the easy bit which has been done many times before.
Designing a mission involving 1000 days in space with no prospect of resupply is the hard bit. And it's the likes of ESA and NASA that have visibly been spending money on research and testing for that bit, not the very successful private launch vehicle supplier and LEO constellation operator.
It's easy if you use additional payload available with bigger rockets.
Just like invention of the rocket engine enabled all kinds of rockets, the ability of having a lot of payload available for the mission enables all kinds of solutions for existing problems. Robotbeat is correct.
I'm sure this question has been addressed already, but why not try a 1-year moon base first? With a hot standby ready to either rescue them or drop a brand new habitat.
Not to mention launching to Mars from the moon is easier (in some respects, not all).
This is exactly what NASA has had on its timeline since the Obama era ("Constellation"). Trump #1 didn't like the slow timeframe (get to the moon faster - "Artemis"). Current plan from Trump/Elon ("let's scrap the space station and the moon and go to Mars ASAP") sounds like an even more accelerated abandonment.
On the contrary, Constellation is from the Bush era. Obama tried to cancel it (with good reason, to be fair!), and then Trump started an accelerated Artemis, which basically combined both the Obama program of record with Constellation.
I think a moon colony would be awesome. We could watch them in near real time. Learn what it actually takes to maintain a habitat while still having a safety net. Yes I know NASA and others have been researching that since the 60s anyway, but it needs a dress rehearsal with modern technology. Go to moon, prove we can sustain N humans, process the waste, recycle the water, make O2, etc. Do it on the lunar surface, then go big.
I do see Trumps side, that if they take decades to get anything done, maybe the project should be scrapped. But space-x has proven they can launch rockets reliably and cheaply, I believe we should use their innovation but to the moon before the red planet.
> It really puts the frustration I have with Musk's constant "we're going to Mars" in context.
This is just the latest version of The Music Man and Marge vs. the Monorail.
Musk is serious about getting rich but not about going to Mars. It's always been a ploy to trick naive tech nerds into sacrificing themselves for the goal of "saving the world".
Tesla is a perfect example of this. A low-cost no-frills electric car would do a lot more for the environment than the vehicles produced by Tesla, which are luxury-priced and continue to (falsely) promise "Full Self Driving". The market is obvious: well-off tech nerds who are made to feel good about themselves that their luxury purchase, with cool technology, is "saving the Earth". (A similar strategy is used by Apple, by the way. Apple convinces people that buying a new iPhone every year or few years is "carbon neutral" and that it's somehow ok to eschew device repairability, upgradability, user battery replacement, etc.) We're told that the plan was to sell cheaper Teslas "later". It's always later. Yet other auto manufacturers have produced cheaper electric vehicles without the self-driving crap, and still for Tesla it's "later". So Musk has $44 billion to spend on Twitter but not on taking lower margins on Tesla vehicles?
We're told now, by Musk, that the biggest barrier to the Mars project is not, say, the gravity on Mars, or the radiation, but rather "the woke mind virus". Uh huh. Con man.
I'm not denying Musk's accomplishments, any more than I'm denying that Trump managed to get himself elected POTUS twice. But they're both con men, and their real goals—power, self-enrichment, self-aggrandizement—have never been the same as what they tell to their followers. They're surely among the best con men on the planet. It feels like all of the top con men are coming together now for the big heist, like Ocean's Eleven.
For sure; as the article points out, a viable trip to Mars requires a ton of investments yet, but Musk is currently helping dismantle NASA and the ISS, probably with the intent of sending more high value contracts to SpaceX.
Any stage in making a mars trip viable is a multi-billion dollar project. Actually arriving on or around mars has no value in itself other than the achievement and some science, but the runup will possibly make SpaceX the wealthiest company in the world. Or at least pull tens, hundreds of billions out of the US economy.
What you're saying doesn't even make any logical sense. Musk is the primary contractor for ISS contracts and given the shit show that Boeing has turned into it's safe to call him the exclusive contractor for ISS contracts.
And most of NASA's budget is not spent doing stuff, but on thinly veiled graft like the SLS which obviously will not be redirected to SpaceX because the goal isn't to achieve anything, but to spend money on interests tied to the people directing the spending.
> What you're saying doesn't even make any logical sense. Musk is the primary contractor for ISS contracts
It makes lots of sense to torch a crowded market & lean-in on heavy-lift first-mover advantage. He will be the only contractor for a hypothetical Mars missions and will have a blank check as soon as the government commits to it - if he doesn't write the bill himself.
SpaceX will lap Blue Origin on heavy lift, while having NASA pay for R&D that will be used by SpaceX to go the asteroid belt and mine precious metals or whatever post-Mars yarn will be spun to make SpaceX a trillion-dollar company, realistic or not.
> Musk is the primary contractor for ISS contracts and given the shit show that Boeing has turned into it's safe to call him the exclusive contractor for ISS contracts.
Just because they're doing fine now, doesn't mean we want to give SpaceX a monopoly in the future.
Reminder: SpaceX was not a thing a few years ago, and NASA throwing money at them could have been considered 'wasteful' when there was a solution that worked already. We are where we are now because the government spread the money around a bit: some of those 'bets' worked out, some did not.
The commercial crew program started in 2011, the same year that the Space Shuttle was retired. From 2011 to 2020 (when SpaceX first sent astronauts to the ISS) we were 100% dependent upon Russia. That's undesirable not because of Russia, but because it's plainly ridiculous for any superpower to not have the power to independently send humans to space! SpaceX also won the exclusive contract for commercial crew. Boeing managed to get this overridden with political connections forcing NASA to not only also accept their bid but to pay their dramatically larger asking price.
All that aside, I actually agree with you in principle! The SpaceX of tomorrow will not necessarily be the SpaceX of today. And having a space economy full of good healthy competition is a great thing for everybody, including SpaceX. But this was not a case of that. This was just an old dysfunctional company relying on some old corrupt politicians to butter some bellies.
Blue origin is doing pretty well. Got partly reusable rocket to orbit recently. NASA has no reusable rocket in development. This is fine, as the private market is doing it, but SLS needs to be retired soon. Maybe after the manned moon landings?
> Musk is the primary contractor for ISS contracts and given the shit show that Boeing has turned into it's safe to call him the exclusive contractor for ISS contracts.
From Musk's perspective, NASA is an unnecessary, inconvenient middleman. Eliminate the public middleman, and everything goes to private companies, in other words, to SpaceX. And it's not just about NASA; the current administration wants to privatize the entire government, including the US Postal Service, for example.
> And most of NASA's budget is not spent doing stuff, but on thinly veiled graft like the SLS which obviously will not be redirected to SpaceX because the goal isn't to achieve anything, but to spend money on interests tied to the people directing the spending.
Musk/DOGE currently controls all federal spending.
> Tesla is a perfect example of this. A low-cost no-frills electric car would do a lot more for the environment than the vehicles produced by Tesla, which are luxury-priced and continue to (falsely) promise "Full Self Driving".
Even getting all cars to be hybrids would be a huge win (either parallel or series / range-extended).`
I don't see any problem in companies making huge profit. We live in a free market there is always an opening for new competitor to offer something at low price point that can be repaired. Nobody is stopping anybody to start such a company.
The reason nobody is able to compete because it takes lot of capital to bring new technology in market. If you cannot hire the best people you will not get the best technology. And no engineer wants to work at a company at pays less.
More profit buffers company from random market events.
We live in a capitalist society. Tesla/Apple are just a by product of the system.
Also, whatever Elon says is should be taken with a grain of salt. He is a salesmen. Hyping stuff up so that people buy.
> I don't see any problem in companies making huge profit.
I didn't say there was. But there is a problem in lying to people, claiming that your goal is to "save the US" or "save the Earth" or "colonize Mars" when it's really profit maximization.
> Also, whatever Elon says is should be taken with a grain of salt. He is a salesmen. Hyping stuff up so that people buy.
Have you tried the latest version of FSD. I recently got a Tesla with it and it is about at the level of someone who has been driving for a few months. Has made one or two non-accident mistakes over the last few months but nothing serious. Sort of a dangerous uncanny valley I have to be careful of and not just forget I need to pay attention still (it tracks your eyes to make sure you look at the road most of the time but you can still zone out if you are not careful).
The proof will be robotaxis in Austin this June. I hope to be able to send my Tesla out to be an Uber to earn money when I sleep sometime late this year or next. Time will tell but we do have re-usable first stages and Starlink already and it is pretty great.
Maybe Musk has no interest in getting humans to Mars, but if this con man builds a rocket that gets cost to orbit in the $10/kg, con me some more please.
I think a lot of people just approaching this topic from largely ignorance are unaware of how hardcore Falcon 9 has actually delivered on its promises, in spite of being mocked by its competitors.
Starship is already well on its way to succeeding, in the big picture
Falcon 9 proved the concept of reusability. Almost everyone does not understand what Starship will do for space travel. Like Musk says, imagine air travel where you throw away the plane after each flight. That is where space travel was at. Hope to go to a space station or the moon in my lifetime (dream about Mars).
Just to play devil's advocate, Isn't he getting the ball rolling? Put aside his unrealistic timelines, at least he's trying to solve the rocketry part of the equation. I feel like this extreme hatred is unwarranted.
It doesn't make sense to send humans except many humans want to go. Those humans are working on the project to go to Mars, not send robots to Mars. We can do both of course.
I would like people to start a civilization on Mars. I would like to go to Mars. I will pay for the privilege to do so or see it happen for othera. Maybe it will. There are many people like me.
I think people are more enthusiastic about robots than justifiable, because they see things like the Atlas robot and imagine that's the future. In reality the first man on Mars will likely discover far more in a week than we have in more than 50 years of probes, or in all probability would in 50 more.
The fundamental problem is that moving parts break. This results in things like rovers being exceptionally conservative in both their design and behavior, out of necessity. For instance Curiosity's drill can only drill to about 6cm, and even then it broke after 7 limited activations, which then took a team of scientists 2 years to come up with a partially effective workaround. A guy on the scene could have fixed it a few minutes, or done just as effective 'drilling' himself with a spoon. We're literally not even scratching the surface of what Mars has to offer.
Another issue is in mobility. That involves lots of moving parts. So Curiosity tends to move around at about 0.018 mph (0.03 km/h) meaning at its average speed it'd take about 2.5 days to travel a mile. But of course that's extremely risky since you really need to make sure you don't bump into a pebble or head into a low value area. So you want human feedback on a ~40 minute round trip total latency on a low bandwidth connection - while accounting for normal working hours on Earth. So in practice Curiosity has traveled a total of just a bit more than 1 mile per year. And as might be expected its tires have also, broken. So it's contemporary travel time would be even worse.
Imagine trying to dig into all the secrets of Earth by traveling around at 1 mile per year, and once every few years (on average) being able to drill hopefully up to 6cm. And all of these things btw are bleeding edge relative to the past. The issue of moving parts break is just an unsolvable issue for now and for anytime in the foreseeable future.
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Beyond all of this, manned spaceflight is inspiring, extremely inspiring. Putting a man on the Moon inspired an entire generation to science and achievement. The same will be true with the first man on Mars. NASA tried to tap into this with their helicopter drone on Mars but people just don't really care about rovers, drones, and probes. It'd be nice to live in a world where kids don't aspire to be friggin streamers when they grow up.
In reality the first man on Mars will likely discover far more in a week than we have in more than 50 years of probes
We can't be so sure. The probes have discovered that Mars has no channels and vegetation. That water is uncommon (then discovered that it is still there in some quantity). They found out precise atmospheric composition, mapped out all major surface features, observed the climate over decades. They discovered perchlorate toxicity of the soil for humans, something that would have been a nasty surprise to a manned crew.
Am not opposed to Mars expeditions in principle, it's an exciting thought. But I just can't see humans contributing all that much on the odd few landings, with a high chance of contaminating whatever traces of life there could be.
For those that were able to attend last week NASA Ames and USGS held the Offworld Resources workshop. Mining companies, advanced sensor tech (like muon tomography), and even genetically modified organisms to capture metals. Many of the questions and thoughts posted in this thread were covered.
Initial manned missions anywhere will never depend on in situ resource utilization, like soil, anywhere. And they will also assume that the environment is toxic until proven otherwise. You want redundancy to ensure that when things go wrong, which they will, it doesn't necessarily mean everybody dies.
Of course though you're completely right that mapping out the rough surface and climatic patterns is critical, but that would have been capable with the first probe to Mars - launched some 53 years ago. There's just really extreme diminishing returns with probes and rovers. For instance these [1] are NASA's highlights for what Perseverance, the latest Mars rover, has achieved in 4 years. To call them uninspiring would be an understatement.
This is because there are increasingly fewer big discoveries to be made. No, an astronaut with a shovel won't excavate a lost Martian city, it'll be more of ISS science but in gravity and with sanitizer smelling dust.
We haven't even realistically begun to explore Mars. There are vast underground cave systems, it's still unknown what lays under the moist surface areas, and so on endlessly. Heck, we haven't even been able to expose subsurface strata. Even searching for metal deposits will be extremely important. But these are things we can't realistically do with rovers anytime in the foreseeable future.
>The fundamental problem is that moving parts break.
So do human bodies, and the extensive life support systems they would depend on in space, which I think was the theme, more than anything, of this particular article.
The only unique think I can personally add here that we're probably a lot more comfortable with high failure rates for machines than even low rates of failure for humans.
This seems to be a problem with rocket/lander technology resulting in a ~900kg weight limit on Curiosity.
According to Internet searches, Starship can bright 100 tons to Mars surface.
A common large Earth backhoe seem to weight 20 tons, so with Starship you can just ship one and it will be capable of driving at normal speeds (up to 100km/h), excavating for meters and not centimeters, etc.
(obviously it would need adaptations since diesel engines need air that isn't present on Mars and EV batteries might have problems with the cold, but it would be a similar weight magnitude)
It's not just the lack of air. You'd need an entirely different power and hydraulic system. And any sort of maintenance, liquid changing, etc is completely out of the question. And you need to be able to ensure you can capably operate it with a ~40 minute round trip time between action and getting a response. And then you need to be able to do all of this with temperatures that regularly drop down to -60C with high radiation levels, and so on.
These issues are why things that act like really poor performing go-karts with a few gizmos attached end up costing billions of dollars and taking years to develop and finally manufacture.
Big part of the problem is how big of a hurdle it is to actually send a robot to Mars. I imagine that once we have a cheap and reliable platform to reach the surface, we could iterate the robots much faster.
If you had a budget for one human mission, or a dozen new robots every two years, which one would you consider more beneficial?
General public interest will vanish once people realize that the journey will last two years and likely start 30 years from now. Oh, and they won't see the event live anywways.
The trip to the Moon was a free trip to Jurassic Park in comparison.
We are self-healing, regenerating, low-power, versatile, autonomous, and most of us have a pretty decent array of sensors built-in, along with some communications equipment that's capable of interpreting the signals from our sensors and transmitting that information to other humans in a remarkable variety of ways. All of these are approximate and relative of course, if someone replies with e.g., "but actually we're not as low power as...", it will be easy to ignore.
Specialized machines can do things humans can't, of course. No single human could have survived as long in the Martian environment as any of the rovers have.
But nobody has yet designed a machine that can do all the things humans can do.
Take the single problem of mobility: many very smart engineers have worked together to develop a set of wheels that can usually move the rovers around their environment without getting stuck or damaged, or at least have a chance of getting unstuck. A human that hasn't climbed a set of stairs in a decade can still outpace the rovers, and do so over more varied terrain, and with less chance of getting stuck.
So, yes, from an engineering point of view, building new robots that can do things and shipping them to Mars to do those things presents a lot of very interesting technical challenges to solve. It's all endless puzzles and little unsung feats of science and engineering -- assuming there is a country left with both the will and the resources and the talent to pursue such things.
But from a human exploration perspective -- our instinctive drive, or compulsion, or whatever it is, that has spread our species across the entire planet -- no machine will ever quite satisfy the desire to have that experience with the sensors we were born with.
My enthusiasm for a human mission to Mars has waned quite a bit in the last few years, largely owing to its most vocal advocate. Still, all the same, I think we should acknowledge that robots are poor substitutes for geologists.
I can certainly agree that humans, regarded as perfected creatures of biological engineering, would make for an extraordinary Mars rover. You can make the case that we even the best among all animals for that job here on Earth (we are that good, a fascinating convo for another thread).
The trouble is space itself is really rough in new and different ways. Even if everything is going right, the radiation is extremely dangerous, both on the journey and on Mars itself. And there's bone decalcification which happens very fast. And life support systems issues become very quickly entangled with all the other engineering issues that can cause cascading failures between systems, so even if you didn't think of (say) engineering failures of how power gets to some component as a life support issue, it can become one due to the interdependence of systems.
> Take the single problem of mobility: many very smart engineers have worked together to develop a set of wheels that can usually move the rovers around their environment without getting stuck or damaged, or at least have a chance of getting unstuck. A human that hasn't climbed a set of stairs in a decade can still outpace the rovers, and do so over more varied terrain, and with less chance of getting stuck.
Yeah, we’ve got great fine motor skills and high dexterity, but are obviously still too dumb to emulate those parts effectively.
What's the timeline on "exhausting all the science collection abilities of robots?" Ten years? Fifteen? There are a lot of potential future robot abilities...
Yes, well, maybe logically speaking that would be true. Practically speaking hardly anyone blinks an eye when 'society' daily sends young (mostly) men into harm's way whether that be by employing them in known dangerous professions such as logging (etc.) or by sending them to war. According to the Geneva Declaration on Armed Violence and Development, more than 526,000 people die each year because of the violence associated with armed conflict and large- and small-scale criminality [1] while the world just keeps on turning. Nobody would even blink an eye if that number changed to 525.000 per year by putting dangerous criminals behind bars and keeping them there or by eradicating some terrorist group somewhere nor would they loose sleep if it changed to 527.000 per year after some conflict somewhere flared up again. Life is not as precious as it is often thought to be by most of us here on this site. Seen in that light it makes a lot of sense to choose 1000 volunteers out of the millions who would show up if asked to go on a mission to Mars, success not at all guaranteed and quite likely to be a one-way trip for the foreseeable future. Mars has been explored by a multitude of probes and rovers so sending the next one, no matter how advanced, will not cause much of a stir. Sending 1000 people to Mars with the intent of establishing an outpost will 'rock the world'. If successful (which is not at all a given) it would be one of the greatest achievements of our species while a successful robot mission would just be another tick on the list.
I think the person you're responding to had a solid point, but he derailed it with his own examples. It's not about "throwing out the value of human life" but appreciating that risk is something that, in many endeavors, is going to remain relatively high even if you make every effort to minimize it.
When we went to the Moon, the obituary for the astronauts was written before they even took off. And the astronauts themselves felt they had somewhere from a 50% to 70% chance of success. Everybody was well aware of the extreme risks, but they still voluntarily participated, because they felt the achievement was worth the risk. And indeed those brave men inspired an entire generation to science and achieved what many believe was still the greatest achievement in humanity's entire history.
The first missions to Mars will always be high risk, because the fundamental issue is that you're always going to be doing a bunch of things that no other human ever has. There's just so many unknown unknowns there that we're going end up getting surprised by something. So all we can do is make sure we have highly capable people and try to prepare as well as we can. But in the end, even when you work to minimize risk as much as you possibly can, that mission will always qualify as 'risky.'
Conversely humans are absurdly bad at statistics - i.e. "an astronaut feels he has a 50 to 70% chance of success"...isn't a real prediction. It isn't based on any failure analysis.
The actual failure analysis and engineering was substantially more confident, because otherwise why go? 50% is a coin-flip, but those odds were already proven wrong by the missions before Apollo 11 anyway (since there was more then 1).
You're doing some improv here based on your intuition when history has a way of surprising us. So what was the "actual" failure analysis and risk percent? It didn't exist. "Mathematical risk analysis was used in Apollo, but it gave unacceptably pessimistic results and was discontinued." [1]
Of course there were working assessments internally and they generally put the figure at about 50%. That figure is from Gene Krantz's excellent book "Failure Is Not an Option." The reason you go is because you cannot find any other practical way to significantly reduce the risk, and are willing to accept the risk you end up with.
Also I feel you're somewhat denigrating the astronauts with your comment by saying their estimations weren't "real". These weren't just adrenaline junkies looking for a wild ride - they were extreme intellectual outliers with higher degrees in aerospace engineering and extensive backgrounds in the development and application/flight of all sorts of aerospace systems. Like that paper also mentions, "The only possible explanation for the astonishing success [of the Apollo Program] – no losses in space and on time – was that every participant at every level in every area far exceeded the norm of human capabilities."
You show a Hollywood quote, I'll raise you a better one:
Space: the final frontier. These are the continuing voyages of the starship Enterprise. Their ongoing mission: to explore strange new worlds; to seek out new lifeforms and new civilizations; to boldly go where no man has gone before
You missed the 'volunteer' part it seems. People have volunteered for expeditions with uncertain outcomes since, well, forever. Some people do their utmost best to tempt fate by climbing skyscrapers and masts without any safety devices, they jump off cliffs in clothing which gives them a slight advantage over gravity, they get into devices which are supposed to keep them alive at depths which would crush them to ¼ of their size if they were to be exposed and more. People used to embark on sailing vessels to trek to unknown places, a practice which started when sailing vessels became a thing. People want to explore frontiers and some people are willing to take great risk to be among the first to do so.
No silly quote from a Hollywood production will keep them from following their drive to boldly go where no man has gone before. Or woman, for that matter.
If you think robots should do everything then you might as well retire the human race. Why even bother to live. Why explore the stars when you can get a robot to do it for you?
If the goal is "put man on Mars" then that's what you gotta do. It's harder to make the argument that you need to do that in the service of science, or even offworld colonies, given the unsuitability and impracticality of those both.
Colonies on Mars are what drove the founding of SpaceX. Elon was looking up NASA's plans about sending humans to Mars and found that they simply didn't exist. He wanted to send a greenhouse to Mars while streaming its growth to get people inspired and thinking big again. NASA wasn't interested, Russia wanted too much $$$, so SpaceX was born. A colony doesn't mean you live there forever - it simply means a permanent human establishment. Some people will want to go back to Earth, some will want to stay on Mars indefinitely.
This is a big part of their obsession with lowering costs to space. When the launch costs are not such a huge economic factor, you have much greater leverage with doing things like building, resupplying, or even engaging in interplanetary commerce.
His main motivation was about making humanity a multiplanetary species, largely as a means of ensuring humanity's continuation. It sounds hyperbolic, but Earth has gone through multiple mass extinction events and we're rather overdue for another. And while those mass extinction events were all natural, there's also endless ways you can imagine us all managing to kill ourselves off. And, critically, all of these hyperbolic scenarios will seem extremely improbable up to the very day that one does inevitably happen. So the best time to start would be 50 years ago. But the second best time would be right now.
So the most logical place to start for this sort of 'humanity guarantee' would be Mars, which shares an oddly large amount in common with Earth. There's a verbose (and rather entertaining read) with lots of first party commentary here. [1]
This has been covered before but saying that Mars would be a “humanity guarantee” is actually extremely illogical, not the most logical. Short of the Earth getting blasted to tiny pieces in some way there is no scenario where Mars is more habitable than Earth. This is the sort of sci-fi Utopianism that this sober article is standing in opposition to. Mars may be the second most habitable place in the solar system and it’s infinitely less habitable than a nuked-out fallout-ridden earth or an overheated green house earth. There is no magic scenario where Mars suddenly ends up with a magnetosphere and an atmosphere.
This logic does not necessitate Mars ever being more habitable than Earth. Imagine one of the countless doomsday scenarios - a large asteroid impact. What kills you is not necessarily the asteroid, but it flinging debris into the sky that blots out the sun, not only creating a massive cold, but also rapidly killing all plants which starts a rapid series of extinction events on up the food chain.
If that happened Earth itself would still, even during the extinction event, be a dramatically more pleasant place than Mars. But nonetheless that event would kill off the overwhelming majority of people on Earth, and very possibly 100%, because it's such a significant change from the status quo we expect to continue on Earth. But having a parallel society or societies would ensure that even in the 100% scenario, life could get back up and organized relatively quickly. And even in the "only" 99% of people killed scenario, the outside help could help to reestablish order and kickstart society.
You could build a better 'colony' on earth to survive that event for way less money/effort/risk than a colony on mars. You aren't going to have a colony on Mars contributing back to the home planet in any meaningful way, and 1% of people left on Earth is still 80,000,000, many more than will be in a Mars colony.
Building colonies in-planet that could survive all possible scenarios would probably be impossible. But even if it were you'd face a pretty simple problem - who would ever want to live for there? You'd likely end up living in conditions that would make life on Mars look pleasant, without any of the upsides that might take people to Mars - adventure, ideology, commercial aspirations, perhaps even religious (you know the Mormons will want a planet or two), and of course 0.3g!
And who knows what the future holds in terms of population sizes? I also strongly disagree on the colonies not being able to engage in exchange. For a silly but very practical example sports in 0.3g are going to be insane. Jordan could jump something like 11ft and stay airborn for several seconds on Mars. That's going to be just be stupidly awesome to watch and play. MMA will look like a something out of a Chinese martial arts movie. For more mundane things, as the price of shipping cargo decreases the number of things available for trade increases. For example wine made in 0.3g will taste very different. Whether that's better or worse is yet to be discovered, but obviously such ideas will have no difficulty finding a market.
For better or for worse Mars (or the Moon) will also probably make amazing retirement places, especially if we can work on the scenery a bit. Taking that load of old bones might not only provide comfort but even increase longevity enabling a weaker heart to keep pumping a bit longer. And so on endlessly.
For me first logical step is to ignore the getting there part. And prove that we can actually build colony here. In suitable location say for example Sahara or Antarctica. After those technological challenges are solved next step is to see how to get it to orbit or make same in orbit. And then we can start thinking how to get all the stuff over there.
There's not really a plausible path to colonies on other planets (or on moons of Jupiter or Saturn) that needs to send humans there soon. Establishing such a colony and getting it working well enough to actually last would be a long term project, and it would be decades before it got to sending people.
Before that there would be a lot of work off Earth, including manned work, but it would be in space or on the Moon.
They key is Lagrange points. Each pair of bodies (Sun/Earth, Earth/Moon, Sun/Jupiter, etc) have 5 points where the gravitational forces from the two bodies balance out in a way that makes it possible for something to orbit that point, even though there is no massive body at that point.
Two of the Lagrange points are stable, meaning that if something in orbit around them is disturbed it still stays around that point. The other three are unstable. Disturbing something there will cause it to get farther and farther away.
You can use this to move things from Lagrange points of one pair (Sun/Earth for example) to Lagrange points of another pair (Sun/Jupiter say) very cheaply. Get it to the starting point, and then nudge it into an unstable orbit that will have it getting farther and farther away. We can calculate these unstable orbits well enough to pick one that at some point is nearly tangent to an orbit of the destination Lagrange point that moves toward that point rather than away. A little nudge them can move our ship into that latter orbit.
The catch is that this is slow. It might take decades or more to make the trip.
The way you would use this in a colonization program is to build a series of unmanned cargo ships. Say a new cargo ship is completed every year. It would be stuffed full of supplies the colony will need, send to an appropriate Sun/Earth Lagrange point, and nudged onto its journey.
Let's say these ships take 30 years to reach the destination. After we've been doing this for nearly 30 years then we'd send a ship with the colonists. That ship uses a fast but expensive orbit. It would only need to carry the colonists, the supplies they need during the trip, and fuel and supplies for an emergency return trip in case when they get there they find some reason that they cannot stay.
Note that it doesn't need to carry any material to actually build the colony, or food and water for the colony. All that is in the cargo ships that are now arriving yearly. (If we are sure that the cargo ships are making it the human transport ship could even omit food, water, and fuel for an emergency return. Those can be on the first cargo ship).
You'd want to build the cargo ships on the Moon, or build them in space using resources from the Moon, because getting from the Moon to Lagrange points takes a lot less energy than getting from the Moon to Lagrange points.
The most plausible path then is to greatly expand industrialization of the Moon and the space near Earth. Probably then expand that to include space bases at some of the Lagrange points.
Then it is time to start working on colonization.
Unfortunately we'd probably not do Mars this way. If I recall correctly the low energy Lagrange transfer orbits to Mars are particularly slow--over a thousand years if I remember correctly.
Seems like the most conservative approach would be to send the return vehicle first, empty. Once it's landed safely on Mars and all systems look good, it would be reasonable to send the human crew in a 2nd vehicle?
I had the same thought, but this has no effect on necessary delta-V. In terms of risk, I suspect it's already baked in to his analysis at some level. The risk comes from human-time-on-planet or time-in-space, which having a return vehicle doesn't change.
Eh, we've done it before. Read up on Magellan's circumnavigation, the colonization of Australia or the Shackleton era of Antarctic exploration.
Of course, the difference is that compared to the conditions that await on Mars, a roaring blizzard on Antarctica is a balmy spring day. The air may be cold but at least it's breathable.
I'm picturing that the safe way forward is to send a 1000 day duration mission to LEO which would remain autonomous except in case of critical failure. Probably a series of them.
Aluminum is a poor material choice for thick radiation shielding, since it produces lots of secondary radiation and it's inefficient due to its high atomic mass. Polyethylene, which is nice and hydrogen-rich, is widely understood to be superior.
An aluminum hull is nice because it does double duty, but you don't need to make it thicker than the structure requires just for radiation purposes. Instead you would add internal shielding. It's also smart to use food (and the resulting waste) and other consumables as shielding, since you need to carry that mass anyway.
I think you misunderstood a diagram; grams of Al per square centimeter is a standardized unit of shielding in the literature, not an engineering choice.
That doesn't matter though. Since it's not representative of the real shielding, it's an inapplicable standard to use for this problem.
You should realize that there's no simple way to convert from aluminum to polyethylene: it's not as simple as "PE is X times better." Due to secondaries aluminum stops improving after 30 g/cm^2,[1] hence why their chart (bottom line) levels out. PE doesn't have that problem, and lower dose rates are achievable versus what the author states.
TL;DR regardless of if you call it a "standard" or not, the author is still using bad math to overstate the actual risk.
I didn't choose AL shielding as the reference standard to use in the literature; I'm sorry it bugs you.
You can read the author's other work, that goes into great detail about different types of shielding, if you want to gain confidence in his math. The upshot is you need many meters of polyethylene to effectively shield the heavy ion component of GCR, which is what the fuss is about.
But the point of that particular diagram is not shielding, but to illustrate the 2-3x uncertainty in estimates of tumor risk based on our poor understanding of high-Z ion exposure.
>I didn't choose AL shielding as the reference standard to use in the literature; I'm sorry it bugs you.
It's not that it "bugs me," it's that it deceptively exaggerates the radiation risk that is achievable by a reasonable thickness of radiation shielding.
>You can read the author's other work, that goes into great detail about different types of shielding
Maybe so, but that doesn't make this paper any less deceptively written.
> The upshot is you need many meters of polyethylene to effectively shield
The diminishing return is reached after only 20-30 cm. See the paper I linked above.
>But the point of that particular diagram is not shielding, but to illustrate the 2-3x uncertainty in estimates of tumor risk
Then it's poorly written. You can illustrate that point without exaggerating the absolute tumor risk (see the vertical axis).
The author puts a Mars mission into a realistic perspective but also, I think there are people who are wired differently than they are.
I'm not a test pilot but I'm a licensed pilot and I'd sign up for a Mars mission in a heartbeat, even if there was a 70% chance of success.
We send people under the ocean for years at a time to live on nuclear submarines in arguable more dangerous and isolated circumstances and they don't blink at the opportunity. To be the first person on another planet? What an incredible, fantastic opportunity. I feel like we will need to return to a place (As a society) where we accept risks that push the boundaries of the human race. Something we had a lot of in the 1960s but not a lot of today.
I don't think any single crew deployment reaches a year.
> more dangerous and isolated circumstances
I think Mars is massively more dangerous and isolated. A submarine can plausibly return to port or surface to breathable air. There is no such option on Mars. Nuclear submarines are much larger than spacecraft and have much more room for comfort options. They have a much larger crew, and the knowledge that this happens all the time from many nations must be of some comfort.
> arguable more dangerous and isolated circumstances
I guess technically anything is arguable, but this seems absurd. Sure there's pressure and cold, but a submarine can hold 100+ people and surface in 10 minutes.
Mars is 10 months away with maybe 10 people. There's no surface. You can't scrub oxygen from the water, hell there's almost no water at all. You won't be crushed by pressure but you'll be bombarded by radiation.
I reluctantly upvoted this for the wealth of scientific/engineering knowledge it contains despite strongly disagreeing with some of its conclusions:
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In recent years, there’s been a remarkable division in space exploration. On one side of the divide are missions like Curiosity, James Webb, Gaia, or Euclid that are making new discoveries by the day. These projects have clearly defined goals and a formidable record of discovery.
On the other side, there is the International Space Station and the now twenty-year old effort to return Americans to the moon. These projects have no purpose other than perpetuating a human presence in space, and they eat through half the country’s space budget with nothing to show for it. Forget even Mars—we are further from landing on the Moon today than we were in 1965.
In going to Mars, we have a choice about which side of this ledger to be on. We can go aggressively explore the planet with robots, benefiting from an ongoing revolution in automation and software to launch ever more capable missions to the places most likely to harbor life.
Or we can stay on the treadmill we’ve been on for forty years, slowly building up the capacity to land human beings on the safest possible piece of Martian real estate, where they will leave behind a plaque and a flag. But we can’t do both.
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1. SpaceX/Starship lower the cost of human space exploration by possibly two orders of magnitude over the Apollo/Space-Shuttle era
2. We can increase the amount of resources allocated to space exploration.
For both of these reasons, we absolutely can pursue both tracks.
I remained neutral on it since I also thought it was an interesting and clearly well researched article, but I think it leaned a bit too heavily on some somewhat inappropriate analogs to things like like with the ISS. It's a deteriorating old station where astronauts need to constantly prepare for orbital reboosts, receiving cargo, running commercial experiments, literally plugging holes more recently, and so on. This doesn't really translate meaningfully to the responsibilities on an interplanetary mission on new hardware.
Similarly alot of his stuff about microgravity just handwaves away the fact that a lot of the mission will be spent in 0.3g. And, in terms of overall effects on the body 0.3g will almost certainly end up being closer to 1g than 0g. It'll make it much easier to do things like exercise and all the "normal" physics of things would be much closer to the environment we all evolved in, than in 0g where everything just gets super funky. In fact I wonder about the viability of simply wearing body weights while on Mars, something that obviously would not work in 0g.
The radiation stuff has also been pretty well researched and isn't likely to be a show-stopper, especially with normal measures for protection like using the water supplies as a shield.
Most of the major negative effects from time in 0g are pretty easy to derive from first principles - like the loss of bone density and muscle mass. The cause is simply a lack of muscular exertion. In 0g you don't really have much of any recourse against this except lots of mostly elastic based exercise, so astronauts on the ISS spend 2+ hours every single day just exercising, and it still isn't enough. On Mars the deterioration will obviously be lesser. And you also have much easier solutions not only in terms of working out but also passive, like the proposed body suits.
Also I'd add that even the less well understood issue like vision decline generally has to do with things 'not going the right way' -- in this specific case 'stuff not going down' increasing the pressure on your ocular region (ever noticed how astronauts all seem to have kind of bloated heads while on the ISS?). On Mars (or any other body with some reasonable degree of gravity) these sort of things won't be a problem.
Good point, we don't have to exactly follow the "astronauts in a small tin can, where everything must work flawlessly" way. With Starship (or its future iteration/successor) we can:
- assemble a quite large interplanetary craft in orbit, with plenty of redundancy in HW and supplies
- drop 50 tons of cargo on Mars beforehand: food (and/or food-growing necessities - packaged soil, hydroponic equipment?), medical supplies, etc.; so that in case of problems, astronauts can survive on Mars for years if need be
napkin for ion drive powered by solar - tech available today (and nuclear as the power source for the ion drive instead of the solar - tomorrow for Mars and beyond) - looks much better than chemical even for Mars. As SpaceX already using ion drives on Starlinks, and the SpaceX will be the one going to Mars, i'd expect that it will be ion drive.
Solar electric propulsion has great specific impulse [i.e., efficient use of propellant] but very low thrust. You're forever spiraling away from and then down into gravity wells.
It's terrific for cargo, but not viable for crews.
I expect the best way to use ion thrusters would be to combine them with chemical engines.
Use chemical engines for the high thrust trans-Mars injection burn so you can exploit the Oberth effect, then use ion thrust to continuously accelerate the ship for a (modest but still helpful) reduction in travel time.
You need about 10KWt per 100kg, i.e. 50m2 of panels. For 10 tons it would be under 5000m2, ie. like 70x70m. The panels do need to be relatively thin. Less than half the mass - 4 tons is the expelled mass (using say those NASA drives with 3500 Isp). And if you get panels at 0.5kg/m2, you'd get to 15km/s in under 2 months with about 3.5 tons for the rest of the ship including payload. More panels - either thinner ones or with less payload - faster time to Mars. Nuclear with ion drive - even better (and the only choice beyond Mars), can get you 35km/s+ (Voyager) or like 70km/s+ with 2 stages in under year.
i'd say i hope for the hybrid - nuclear (especially fusion once we get to it) generates power while something like in your second link collects the mass for expelling from the drive. The nuclear can work far beyond Solar system while the running out of the expelling mass is the main limiting factor here.
You've definitely missed some decimals somewhere and/or are not considering the amount of thrusters needed. Ion thrusters total thrust is measured in the millinewtons and they have a very poor thrust:weight ratio (which does not account for the energy source mass). They're also relatively unreliable making them generally unfit for round trip missions without excessive redundancy which further increases the mass and thus the number of thrusters needed. Almost like a sort of microcosm of the tyranny of the rocket equation.
7KW NASA drive weight about 10kg. At 10KW it would expel about 8milligram/second for 0.3N thrust (even with paltry 50% efficiency). It will get ship of 100kg total starting mass to 15km/s in under 2 months spending under 40kg expelled mass. The arithmetic is very simple. (my favorite arithmetic here is 3 stage nuclear powered ion drive ship with increased voltage resulting in ~35000 Isp and thus getting 1000-1500km/s in 100 years, and thus 1000 years fly-by to Alpha Centauri, with the tech basically available today :)
>They're also relatively unreliable
Given their simplicity i think it is among the most reliable pieces of tech around. 5 years non-stop - no issues :
Note that all this is just NASA so far without SpaceX/Musk applying their engineering magic yet which i think would significantly improve the mass, efficiency, etc.
Acceleration = 0.0000236m/s (acceleration = force / mass)
Seconds in 2 months = 5259600
Final Velocity after 2 months = 277 miles per hour (0.124km/s)
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This is an extremely naive and optimistic calculation since I'm assuming the engine is weightless and does not require fuel or power. It's easier that way and still emphasizes the point perfectly fine. You're gonna need a lot more engines to get anywhere. And of course a 10 ton ship is not practical. The goal for Starship is to to have a payload in the hundreds of tons, let alone the entire vessel's mass.
You also only have half the distance to accelerate, because you then need to turn around and decelerate the remaining distance. And we're also ignoring landing/takeoff which obviously isn't happening.
>I'm assuming the engine is weightless and does not require fuel or power.
10KW 10kg engine plus 40 kg expelled mass per 100kg total starting mass. Thus for 10000kg - 1000kg of 100 x 10kg 10KW engines, 4 tons expelled mass, 2.5 tons - solar panels providing power. 1 engine - 0.3N, 100 engines - 30N. 15km/s in under 2 months, plus 2 months deceleration. The same for 100ton ship or 1000ton.
>landing/takeoff
that is by local chemical Starships "shuttles" which would transfer people and cargo to/from the interplanetary ships. Using Starship shuttles to fuel the interplanetary Starship, though chemical one, has long been in the published SpaceX/Musk plans.
Has there been discussions on who to send on a "man"ned mission? Apollo had height and weight limitations for an average male, and now that DEI is dead, I wonder if it's more prudent to proritize sending smaller people (really light women) because sexual dimorphism seems to be a thing in the military.
Women tend to be substantially more susceptible to radiation related issues. [1] In reality though I think the main issue (outside of competence/merit) will be making sure people stay psychologically sound being tens of millions of miles away from Earth, for years. So in that case I wouldn't be surprised if they end up prioritizing highly capable couples.
I think if long term supplies bottleneck, one would pick for physiology that requires less, i.e. 100lb person consumes ~50-60% calories as 200lb person. Or for same supplies you get much more brains/work done. Light lesbians with no need to worry about pregnacy fits the bill.
During the second world war the British not so famously (it's not like it's something you brag about) spent a lot of money and effort building extremely heavy tanks or assault guns designed to help a spearhead a breach of the Siegfried line. They turned out to be mostly unnecessary due to a combination of factors that can be roughly summed up as "quantity has a quality all its own" and the projects were steadily cancelled as the war in Europe wound down.
It's likely that some of these big unknown problems will similarly evaporate or prove to be easily solved once we actually do stuff like put humans in deep space ad on the moon for serious chunks of time.
This is a very good article.
It really puts the frustration I have with Musk's constant "we're going to Mars" in context. Yes, a big rocket is necessary prerequisite for Mars. No, it is not the only problem you need to solve.
And also having worked with the reality of human spaceflight operations, we are just not ready yet to send a spacecraft into deep space for months on end. It's easy to throw out blithe statements that we "just need a big spaceship", or we'll use ion drives or some other such tech, but the reality is way more messy than that. We just aren't ready yet and we won't be for some time.
The large rocket adddresses basically all the problems.
Time between resupply? Well, you can just take a bunch of resupply missions with you. Most stuff is packed ahead of time, except fresh veggies and fruits, but deep freezers can keep the nutritional value of those nearly as well as being fresh.
Redundancy/reliability? Bring the spare pool with you instead of keeping it on the surface for resupply flights. Bring two different systems.
Long duration life support? Enough mass allows you to avoid it all together if you like. This still has not sunk in to most of the fairly educated people who opine on this topic. Simple life support systems are VERY reliable, and the advantage of advanced life support systems is they reduce mass. If you don’t need the mass reduction, you don’t need the advanced life support.
Far from medical care? Small crew sizes are a mass constraint. More mass means you can afford large crews with dedicated medical personnel. And the equipment to go allow with it.
Also applies to radiation shielding (mass) and even partial gravity (centrifugal gravity is well known as a replacement but for some inexplicable reason is avoided… and yea, even short arm centrifuge is useful and could be used on the surface… the disorienting effects are actually manageable, and while in space, a tether can be used to enable long arm centrifugal gravity with little Coriolis effect).
Transit times can also be reduced significantly with refueling. 80-120 day transits are feasible, not just the most efficient 150-210 day transits for long stay. The surface of Mars also has significant radiation shielding in spite of the thin atmosphere. The Mars rover Curiosity measures the same radiation equivalent on Mars’s surface as on ISS today. Mars rover Perseverance also demonstrated production of unlimited oxygen from the Martian CO2 atmosphere using electricity. Regolith could also be used to enhance radiation shielding. This is before discussing water mining (and even that can be done without touching regolith, just the air using the WAVAR technique… useful for crew consumption although this method doesn’t scale up to producing enough for propellant very well).
There is no a single hazard or obstacle to a Mars mission that isn’t at least partially mitigated by having a lot more mass capability, ie a big and cheap reusable rocket (capable of landing on Mars and aerobraking).
Well there is the "one-way trip" version which takes out some risk but trades the risk of losing 4 astronauts for the risk of losing 400 or more.
Since it's not plausible that you could bring anything back from Mars that would be worth enough to make colonization practical from the perspective of Earth, Mars colonists would always have to assume that the last rocket that was launched is the last that will arrive. From their point of view, they'd want to be able to manufacture absolutely everything locally as soon as possible.
It's one thing to say "we can make unlimited oxygen from the soil never mind the atmosphere", it's another to find a source of nitrogen or other inert gas that makes it possible to live in an atmosphere that doesn't make everything into a firetrap. It's one thing to spin the kind of science fiction that Gerard K. O'Neill did, but his disciple Eric Drexler realized just how bad the problem of 'advanced manufacturing' is and went off to follow his own El Dorado, writing a fascinating book [1] about a class of systems that 'just don't work' [2]
Not to say that the goal of "a population of 10,000 people being able to make everything that 8,000,000,000 can make" is unattainable, even if we can get it down to an advanced industrial base being supported by 10,000,000 people it would be a game-changer here on Earth. I can see paths there, but it's by no means a bird in the hand.
[1] https://www.amazon.com/Nanosystems-P-K-Eric-Drexler/dp/04715...
[2] https://latecomermag.com/article/what-happened-to-molecular-...
The atmosphere of Mars is 3% nitrogen, so nitrogen can be extracted just from the atmosphere.
And I agree 10,000 is far too small for self sustaining settlement. A million is the minimum. Even 10 million would be a challenge.
It would probably be smarter to launch multiple payloads than have everything in one big payload, a fire can take out the primary and redundant supplies for example.
That said, throwing more money and gear against the problem will likely be the way to go. Besides, it doesn't actually have to be done all in one go, if the vision of SpaceX is that of mass production, they can launch a whole chain of Spaceship sized payloads towards Mars years before a human crew is sent that way, giving them supplies and whatnot on the way, in orbit, and on the surface. That'll require a lot of planning and automation though.
SpaceX has always mentioned sending multiple ships at once for redundancy, starting with uncrewed precursors sending supplies ahead of time.
This is irrelevant and completely ignores the OP. We've had rockets capable of going to Mars since the 60s. More rockets do not solve the problem. Cheaper rockets do not solve the problem. Please read the article.
Biggest problems are microgravity, radiation and lack of redundancies of various kinds. All are solvable by adding payloads.
Please read my comment. More mass makes solving virtually every challenge of Mars missions far, far easier.
https://news.ycombinator.com/user?id=jamleha
I wonder why my comment got downvoted? I thought it was pretty thoughtful and addressed the comment and article’s claims pretty directly.
We send spacecraft to deep space for decades on end, not just months. Oh, you meant CREWED spacecraft…
We are in fact far more ready for sending crewed missions to Mars than we were to sending crewed missions to the Moon when JFK made his Moon speech. We had only barely launched an astronaut on a suborbital flight at that time! And yet 7 years later…
On the one side, you have a point, but on the other... as the article mentioned, a moon round trip can be done in the span of a week, they can set the craft on a trajectory so that it has a free return even if the thing becomes uncontrollable. Not so for Mars trips, after a few hours they're committed to the trip. The article then mentions everything that can go wrong.
I'm confident that if they tried to launch a Mars mission with current-day technology now, the crew wouldn't make it. Nobody's ever been in space for that long, to start - yet Musk wants to deorbit the ISS, the only viable platform at the moment to even try and simulate a two year space trip.
“Current day technology” is sort of poorly defined because you can make new technology in one day. “Current tech” is a fake constraint, because even preparing for a launch in two years, you’d be developing new technology all along the way.
The annoying thing is that we could’ve been simulating long duration partial gravity using artificial gravity for decades, but NASA has refused to do so. For inexplicable reasons. If I had to guess, it’s due to the microgravity research community fiefdoms who have made a career of microgravity health effects and so don’t like the idea of directly addressing them using artificial gravity as it makes a whole career’s worth of work largely obsolete.
> you can make new technology in one day.
Not if you want it dependable enough to entrust a multi billion dollar project and several people’s lives to it.
People talk about the moon mission like some massive conquest of space, but we needed to get the fuck off the moon much past sunrise or astronauts would have cooked. It was based on extremely limited oxygen supplies and involved significant radiation exposure that was only ok because again we ran away from an extremely inhospitable environment before things went wrong.
Even today the ISS benefits from earths magnetic field, its space light not a true replica of a mars mission.
The "To the Moon" speech was made in 1962 when we had basically no knowledge of space. We'd only sent a man into Low Earth Orbit for the first time a few months prior. 7 years later we'd land a man on the Moon. And we'd repeat this several times over until Nixon effectively cancelled the human space program in 1972. Obviously 7 years is not one day, but I think 1 day was clearly figurative rather than literal.
The biggest problem is that people have really lost the ability to think big. There's always infinite reasons to not do something, and there will never be a perfect time. So at some point you simply have to choose to push forward. Like Kennedy put it:
"We choose to go to the moon. We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others, too."
> The "To the Moon" speech was made in 1962 when we had basically no knowledge of space.
Talk about hyperbole.
The moon mission has been prepared for before that speech took place. It wasn’t just starting from scratch and hitting the moon in 7 years, instead the speech was more public disclosure of a deadline that looked achievable but would hit after his presidency (1960 + 8 being less than before the decade is out: 1970).
The biggest problem is we already did the easy stuff. Playing tag with the moon is unbelievably easier than a permanent moon base or landing on Mars and getting back to earth.
Obviously we'd been wanting to go to the Moon before that speech, but there was no secret technology that we were just being coy about. We still knew nothing, had nothing and were in the process of figuring out what John Glenn's fireflies were during a flight where, if he wasn't such an uncannily good pilot, he probably would have died.
Saying we'd be on the Moon in 7 years was not something that looked achievable except to the most fanatical of enthusiasts. To the average layman it would have sounded no less impossible than me saying we'll have a man on Mars in 7 years from today. And landing on Mars in many ways will be much easier than the Moon. Not only is the terrain broadly more hospitable, but you have an atmosphere to enable aerobraking which simplifies both landing and braking and enables various options (like some sort of parachute staging or backup). The biggest and really only complexity with Mars is its distance. Outside of that it's easy mode.
> To the average layman
That’s a meaningless yardstick here. People at NASA definitely thought hitting that target was achievable before the speech.
> Landing on Mars
Landing isn’t the issue. Get people there alive and having enough deltaV to get back is.
On the contrary, we can easily get people there alive. What exactly do you think is beyond our capacity to send crew to Mars while still being alive? Crew regularly do year long expeditions on ISS (edited for clarity), with total radiation dose similar to Mars transit (and show no measurable effects of that radiation).
Again, I’m addressing the point “getting them there alive”. Unquestionably, we know how to get crew to Mars alive, and even for the full mission duration, radiation isn’t even in the top 10 of the hazards that could actually kill them during the mission. (It’s a long term hazard, comparable to lung cancer if you’re a cigarette smoker.)
The world record duration still sits at 438-days after 35 years. We limit people below that due to medical issues, suggesting no we don’t know how to safely do multi year space flight.
It’s possible people spending significant time on the surface of mars would recover, but that’s more speculation than proven.
No one has ever done a "years long" expedition to ISS, and the radiation flux in transit to Mars, in particular GCR dose, is much higher than experienced on the space station.
I’m well aware, just mistyped. The total equivalent radiation dose on a fast transit to Mars is less than some ISS expeditions.
Note that the magnetic field only deflects lower energy galactic cosmic rays which have a lower gyro radius than the real whoppers. The magnetic field is less important to overall radiation shielding than the earth’s atmosphere.
Total GCR dose is 3-5x in transit to Mars compared to what you get on ISS; on the Martian surface it's from 1.5-2x the ISS dose. (see https://www.swsc-journal.org/articles/swsc/pdf/2020/01/swsc2...).
On a long-stay Mars mission, that adds up to 12-18 times the accumulated GCR exposure compared to a six-month ISS increment.
No, NASA also didn't think it was possible at the time. There's an informative little paper here. [1] It only gets more informative from the first sentence, "Mathematical risk analysis was used in Apollo, but it gave unacceptably pessimistic results and was discontinued." By the time of the launch to the Moon NASA's internal estimates were looking at around a 50% chance of success based on Gene Krantz's (mission controller) "Failure is Not an Option" book.
It was a mission they dedicated themselves to, and humans have this way of making things happen when we actually set our minds to tasks. A reality that's often been lost in modern times as we have mostly moved away from pursuing, let alone achieving, great things in the real world. One of the many reasons to get humans on Mars.
[1] - https://ntrs.nasa.gov/api/citations/20190002249/downloads/20...
You’re confusing specific low odds of success for “didn't think it was possible.”
The Apollo missions got unbelievably lucky in that none catastrophically failed despite multiple close calls. However, if you’re willing to try multiple times the odds any mission being successful is much better than every mission being successful.
IE: Six missions landed on the moon. If they each had independent 50% odds then six heads is a long way from impossible ~1.6%, but at least 1 head is quite likely ~98.4%. I doubt we would have tried for a 6th mission after 5 failures in a row, but the point is definitions of success matter a great deal here.
Similarly failures improve odds of success in the future because you learn from mistakes and success means the system is functional eliminating some risks.
What I'm demonstrating is that we indeed knew basically nothing. There was no secret tech or expectation of success. Mathematical models doomed the entire idea to failure, and all the way up to the day of the launch people who spent years in a bubble of optimism still didn't really expect more than a 50% chance of success.
> a 50% chance of success.
On that specific launch, which is another way of saying they believed the project had a very good chance of having someone walking on the moon. Failure there wouldn’t even mean people died, just that they didn’t walk on the moon and then safely get back on that mission.
Note that Mars’ surface has a similar radiation dose as ISS, as measured by the Curiosity rover. (This includes the quality factor.)
It does not; see the paper cited in my other reply to you. GCR dose is 1.5-2x on Mars compared to ISS.
The mention of "quality factor" here just begs the question. The reason we need research on biological effects of high-Z ion exposure is that it has a different mechanism of damage, not captured by that paradigm.
A significant part of that is because it’s much further from the sun.
A hypothetical 500 day mars mission is ~1 Sv optimistically which is something like 5% fatal cancer risk. A 3 year mission you’re well above that even before considering solar storms etc.
I think many would sign up for a mars mission especially as treatment improves, but there’s only so much wiggle room here.
> We send spacecraft to deep space for decades on end, not just months. Oh, you meant CREWED spacecraft…
The track record for successfully landing on Mars isn't that awesome:
> Historically, counting all missions by all countries, there has been about a 50% success rate at Mars — and the odds of successfully landing on Mars are only about 1 in 3.
* https://www.lpi.usra.edu/features/ala_msl/
That isn't a very useful statistic - all you should really glean from it is that landing on Mars is hard. The US has done it 9 out of the 10 times it tried, so it seems reasonable that it would succeed.
https://en.wikipedia.org/wiki/List_of_Mars_landers
It was done by NASA, who have a culture of triple/ quadriple checking and being very careful about mitigating risk in ways that may seem inefficient to some. I don't see NASA leading the effort to Mars in any meaningful way besides being a conduit for money from the treasury.
If NASA astronauts are on board, they will be triple and quadruple checking things, like they did for commercial crew and are doing for HLS.
> We are in fact far more ready for sending crewed missions to Mars than we were to sending crewed missions to the Moon when JFK made his Moon speech
When JFK made the speech, it was in the middle if the cold war and there was a realistic fear that the "capitalist way if life" could be beaten by command economics of the Soviet Union in cutting edge science and rocketry, justifying the huge amounts invested in the space race. What is the impetus now? We're all about government efficiency in cutting the social-safety nets, scientific research, but we'll carve out a Mars mission "because it's hard"?
We are, in fact, in the middle of a Cold War again. Also, our economy is far larger and we have launch technology that makes such efforts far cheaper/
A big rocket is probably the biggest obvious hurdle. What are other people doing to get us to mars that is better than musk's approach?
No, the biggest hurdle is having astronauts survive the journey (health and successful landing/departure of Mars). It would be over 3 years in space to round trip to Mars with current tech. We haven't had an astronaut in space continuously over ~1 year...the body suffers tremendously in a low gravity environment and you would have to handle SO many side effects and redundancies in life support etc.
Artificial gravity would address those issues. The big rocket (ie mass margin) also addresses life support redundancies (and allows you to use simpler, much more reliable methods like used on short duration spaceflights).
No, the big rocket is the easy bit which has been done many times before.
Designing a mission involving 1000 days in space with no prospect of resupply is the hard bit. And it's the likes of ESA and NASA that have visibly been spending money on research and testing for that bit, not the very successful private launch vehicle supplier and LEO constellation operator.
It's easy if you use additional payload available with bigger rockets.
Just like invention of the rocket engine enabled all kinds of rockets, the ability of having a lot of payload available for the mission enables all kinds of solutions for existing problems. Robotbeat is correct.
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I'm sure this question has been addressed already, but why not try a 1-year moon base first? With a hot standby ready to either rescue them or drop a brand new habitat.
Not to mention launching to Mars from the moon is easier (in some respects, not all).
This is exactly what NASA has had on its timeline since the Obama era ("Constellation"). Trump #1 didn't like the slow timeframe (get to the moon faster - "Artemis"). Current plan from Trump/Elon ("let's scrap the space station and the moon and go to Mars ASAP") sounds like an even more accelerated abandonment.
On the contrary, Constellation is from the Bush era. Obama tried to cancel it (with good reason, to be fair!), and then Trump started an accelerated Artemis, which basically combined both the Obama program of record with Constellation.
I think a moon colony would be awesome. We could watch them in near real time. Learn what it actually takes to maintain a habitat while still having a safety net. Yes I know NASA and others have been researching that since the 60s anyway, but it needs a dress rehearsal with modern technology. Go to moon, prove we can sustain N humans, process the waste, recycle the water, make O2, etc. Do it on the lunar surface, then go big.
I do see Trumps side, that if they take decades to get anything done, maybe the project should be scrapped. But space-x has proven they can launch rockets reliably and cheaply, I believe we should use their innovation but to the moon before the red planet.
> It really puts the frustration I have with Musk's constant "we're going to Mars" in context.
This is just the latest version of The Music Man and Marge vs. the Monorail.
Musk is serious about getting rich but not about going to Mars. It's always been a ploy to trick naive tech nerds into sacrificing themselves for the goal of "saving the world".
Tesla is a perfect example of this. A low-cost no-frills electric car would do a lot more for the environment than the vehicles produced by Tesla, which are luxury-priced and continue to (falsely) promise "Full Self Driving". The market is obvious: well-off tech nerds who are made to feel good about themselves that their luxury purchase, with cool technology, is "saving the Earth". (A similar strategy is used by Apple, by the way. Apple convinces people that buying a new iPhone every year or few years is "carbon neutral" and that it's somehow ok to eschew device repairability, upgradability, user battery replacement, etc.) We're told that the plan was to sell cheaper Teslas "later". It's always later. Yet other auto manufacturers have produced cheaper electric vehicles without the self-driving crap, and still for Tesla it's "later". So Musk has $44 billion to spend on Twitter but not on taking lower margins on Tesla vehicles?
We're told now, by Musk, that the biggest barrier to the Mars project is not, say, the gravity on Mars, or the radiation, but rather "the woke mind virus". Uh huh. Con man.
I'm not denying Musk's accomplishments, any more than I'm denying that Trump managed to get himself elected POTUS twice. But they're both con men, and their real goals—power, self-enrichment, self-aggrandizement—have never been the same as what they tell to their followers. They're surely among the best con men on the planet. It feels like all of the top con men are coming together now for the big heist, like Ocean's Eleven.
For sure; as the article points out, a viable trip to Mars requires a ton of investments yet, but Musk is currently helping dismantle NASA and the ISS, probably with the intent of sending more high value contracts to SpaceX.
Any stage in making a mars trip viable is a multi-billion dollar project. Actually arriving on or around mars has no value in itself other than the achievement and some science, but the runup will possibly make SpaceX the wealthiest company in the world. Or at least pull tens, hundreds of billions out of the US economy.
What you're saying doesn't even make any logical sense. Musk is the primary contractor for ISS contracts and given the shit show that Boeing has turned into it's safe to call him the exclusive contractor for ISS contracts.
And most of NASA's budget is not spent doing stuff, but on thinly veiled graft like the SLS which obviously will not be redirected to SpaceX because the goal isn't to achieve anything, but to spend money on interests tied to the people directing the spending.
> What you're saying doesn't even make any logical sense. Musk is the primary contractor for ISS contracts
It makes lots of sense to torch a crowded market & lean-in on heavy-lift first-mover advantage. He will be the only contractor for a hypothetical Mars missions and will have a blank check as soon as the government commits to it - if he doesn't write the bill himself.
SpaceX will lap Blue Origin on heavy lift, while having NASA pay for R&D that will be used by SpaceX to go the asteroid belt and mine precious metals or whatever post-Mars yarn will be spun to make SpaceX a trillion-dollar company, realistic or not.
> Musk is the primary contractor for ISS contracts and given the shit show that Boeing has turned into it's safe to call him the exclusive contractor for ISS contracts.
Just because they're doing fine now, doesn't mean we want to give SpaceX a monopoly in the future.
Reminder: SpaceX was not a thing a few years ago, and NASA throwing money at them could have been considered 'wasteful' when there was a solution that worked already. We are where we are now because the government spread the money around a bit: some of those 'bets' worked out, some did not.
The commercial crew program started in 2011, the same year that the Space Shuttle was retired. From 2011 to 2020 (when SpaceX first sent astronauts to the ISS) we were 100% dependent upon Russia. That's undesirable not because of Russia, but because it's plainly ridiculous for any superpower to not have the power to independently send humans to space! SpaceX also won the exclusive contract for commercial crew. Boeing managed to get this overridden with political connections forcing NASA to not only also accept their bid but to pay their dramatically larger asking price.
All that aside, I actually agree with you in principle! The SpaceX of tomorrow will not necessarily be the SpaceX of today. And having a space economy full of good healthy competition is a great thing for everybody, including SpaceX. But this was not a case of that. This was just an old dysfunctional company relying on some old corrupt politicians to butter some bellies.
Blue origin is doing pretty well. Got partly reusable rocket to orbit recently. NASA has no reusable rocket in development. This is fine, as the private market is doing it, but SLS needs to be retired soon. Maybe after the manned moon landings?
> Musk is the primary contractor for ISS contracts and given the shit show that Boeing has turned into it's safe to call him the exclusive contractor for ISS contracts.
From Musk's perspective, NASA is an unnecessary, inconvenient middleman. Eliminate the public middleman, and everything goes to private companies, in other words, to SpaceX. And it's not just about NASA; the current administration wants to privatize the entire government, including the US Postal Service, for example.
> And most of NASA's budget is not spent doing stuff, but on thinly veiled graft like the SLS which obviously will not be redirected to SpaceX because the goal isn't to achieve anything, but to spend money on interests tied to the people directing the spending.
Musk/DOGE currently controls all federal spending.
> Tesla is a perfect example of this. A low-cost no-frills electric car would do a lot more for the environment than the vehicles produced by Tesla, which are luxury-priced and continue to (falsely) promise "Full Self Driving".
Even getting all cars to be hybrids would be a huge win (either parallel or series / range-extended).`
I don't see any problem in companies making huge profit. We live in a free market there is always an opening for new competitor to offer something at low price point that can be repaired. Nobody is stopping anybody to start such a company.
The reason nobody is able to compete because it takes lot of capital to bring new technology in market. If you cannot hire the best people you will not get the best technology. And no engineer wants to work at a company at pays less.
More profit buffers company from random market events.
We live in a capitalist society. Tesla/Apple are just a by product of the system.
Also, whatever Elon says is should be taken with a grain of salt. He is a salesmen. Hyping stuff up so that people buy.
> I don't see any problem in companies making huge profit.
I didn't say there was. But there is a problem in lying to people, claiming that your goal is to "save the US" or "save the Earth" or "colonize Mars" when it's really profit maximization.
> Also, whatever Elon says is should be taken with a grain of salt. He is a salesmen. Hyping stuff up so that people buy.
Exactly my point.
Have you tried the latest version of FSD. I recently got a Tesla with it and it is about at the level of someone who has been driving for a few months. Has made one or two non-accident mistakes over the last few months but nothing serious. Sort of a dangerous uncanny valley I have to be careful of and not just forget I need to pay attention still (it tracks your eyes to make sure you look at the road most of the time but you can still zone out if you are not careful).
The proof will be robotaxis in Austin this June. I hope to be able to send my Tesla out to be an Uber to earn money when I sleep sometime late this year or next. Time will tell but we do have re-usable first stages and Starlink already and it is pretty great.
Maybe Musk has no interest in getting humans to Mars, but if this con man builds a rocket that gets cost to orbit in the $10/kg, con me some more please.
> but if this con man builds a rocket that gets cost to orbit in the $10/kg, con me some more please.
Most cons would be great opportunities if they followed through, the problem is the "having no realistic path to following through" part
I think a lot of people just approaching this topic from largely ignorance are unaware of how hardcore Falcon 9 has actually delivered on its promises, in spite of being mocked by its competitors.
Starship is already well on its way to succeeding, in the big picture
Falcon 9 proved the concept of reusability. Almost everyone does not understand what Starship will do for space travel. Like Musk says, imagine air travel where you throw away the plane after each flight. That is where space travel was at. Hope to go to a space station or the moon in my lifetime (dream about Mars).
Just to play devil's advocate, Isn't he getting the ball rolling? Put aside his unrealistic timelines, at least he's trying to solve the rocketry part of the equation. I feel like this extreme hatred is unwarranted.
> The only way to explore Mars in our lifetime is to ditch the requirement that people accompany the machinery.
It just doesn't make sense to me to send humans. Exhaust the science collection of robots first.
It doesn't make sense to send humans except many humans want to go. Those humans are working on the project to go to Mars, not send robots to Mars. We can do both of course.
I would like people to start a civilization on Mars. I would like to go to Mars. I will pay for the privilege to do so or see it happen for othera. Maybe it will. There are many people like me.
I think people are more enthusiastic about robots than justifiable, because they see things like the Atlas robot and imagine that's the future. In reality the first man on Mars will likely discover far more in a week than we have in more than 50 years of probes, or in all probability would in 50 more.
The fundamental problem is that moving parts break. This results in things like rovers being exceptionally conservative in both their design and behavior, out of necessity. For instance Curiosity's drill can only drill to about 6cm, and even then it broke after 7 limited activations, which then took a team of scientists 2 years to come up with a partially effective workaround. A guy on the scene could have fixed it a few minutes, or done just as effective 'drilling' himself with a spoon. We're literally not even scratching the surface of what Mars has to offer.
Another issue is in mobility. That involves lots of moving parts. So Curiosity tends to move around at about 0.018 mph (0.03 km/h) meaning at its average speed it'd take about 2.5 days to travel a mile. But of course that's extremely risky since you really need to make sure you don't bump into a pebble or head into a low value area. So you want human feedback on a ~40 minute round trip total latency on a low bandwidth connection - while accounting for normal working hours on Earth. So in practice Curiosity has traveled a total of just a bit more than 1 mile per year. And as might be expected its tires have also, broken. So it's contemporary travel time would be even worse.
Imagine trying to dig into all the secrets of Earth by traveling around at 1 mile per year, and once every few years (on average) being able to drill hopefully up to 6cm. And all of these things btw are bleeding edge relative to the past. The issue of moving parts break is just an unsolvable issue for now and for anytime in the foreseeable future.
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Beyond all of this, manned spaceflight is inspiring, extremely inspiring. Putting a man on the Moon inspired an entire generation to science and achievement. The same will be true with the first man on Mars. NASA tried to tap into this with their helicopter drone on Mars but people just don't really care about rovers, drones, and probes. It'd be nice to live in a world where kids don't aspire to be friggin streamers when they grow up.
In reality the first man on Mars will likely discover far more in a week than we have in more than 50 years of probes
We can't be so sure. The probes have discovered that Mars has no channels and vegetation. That water is uncommon (then discovered that it is still there in some quantity). They found out precise atmospheric composition, mapped out all major surface features, observed the climate over decades. They discovered perchlorate toxicity of the soil for humans, something that would have been a nasty surprise to a manned crew.
Am not opposed to Mars expeditions in principle, it's an exciting thought. But I just can't see humans contributing all that much on the odd few landings, with a high chance of contaminating whatever traces of life there could be.
For those that were able to attend last week NASA Ames and USGS held the Offworld Resources workshop. Mining companies, advanced sensor tech (like muon tomography), and even genetically modified organisms to capture metals. Many of the questions and thoughts posted in this thread were covered.
https://www.investmets.com/nasa-workshops-aim-to-merge-on-an...
Initial manned missions anywhere will never depend on in situ resource utilization, like soil, anywhere. And they will also assume that the environment is toxic until proven otherwise. You want redundancy to ensure that when things go wrong, which they will, it doesn't necessarily mean everybody dies.
Of course though you're completely right that mapping out the rough surface and climatic patterns is critical, but that would have been capable with the first probe to Mars - launched some 53 years ago. There's just really extreme diminishing returns with probes and rovers. For instance these [1] are NASA's highlights for what Perseverance, the latest Mars rover, has achieved in 4 years. To call them uninspiring would be an understatement.
[1] - https://science.nasa.gov/mission/mars-2020-perseverance/scie...
This is because there are increasingly fewer big discoveries to be made. No, an astronaut with a shovel won't excavate a lost Martian city, it'll be more of ISS science but in gravity and with sanitizer smelling dust.
We haven't even realistically begun to explore Mars. There are vast underground cave systems, it's still unknown what lays under the moist surface areas, and so on endlessly. Heck, we haven't even been able to expose subsurface strata. Even searching for metal deposits will be extremely important. But these are things we can't realistically do with rovers anytime in the foreseeable future.
> But these are things we can't realistically do with rovers anytime in the foreseeable future.
If you read the article, you'll see that these are things that we can't realistically do with humans anytime in the foreseeable future.
>The fundamental problem is that moving parts break.
So do human bodies, and the extensive life support systems they would depend on in space, which I think was the theme, more than anything, of this particular article.
The only unique think I can personally add here that we're probably a lot more comfortable with high failure rates for machines than even low rates of failure for humans.
This seems to be a problem with rocket/lander technology resulting in a ~900kg weight limit on Curiosity.
According to Internet searches, Starship can bright 100 tons to Mars surface.
A common large Earth backhoe seem to weight 20 tons, so with Starship you can just ship one and it will be capable of driving at normal speeds (up to 100km/h), excavating for meters and not centimeters, etc.
(obviously it would need adaptations since diesel engines need air that isn't present on Mars and EV batteries might have problems with the cold, but it would be a similar weight magnitude)
It's not just the lack of air. You'd need an entirely different power and hydraulic system. And any sort of maintenance, liquid changing, etc is completely out of the question. And you need to be able to ensure you can capably operate it with a ~40 minute round trip time between action and getting a response. And then you need to be able to do all of this with temperatures that regularly drop down to -60C with high radiation levels, and so on.
These issues are why things that act like really poor performing go-karts with a few gizmos attached end up costing billions of dollars and taking years to develop and finally manufacture.
And why all the people involved cry tears of joy when they hear, "We're safe on Mars" after 7 minutes of terror.
Big part of the problem is how big of a hurdle it is to actually send a robot to Mars. I imagine that once we have a cheap and reliable platform to reach the surface, we could iterate the robots much faster.
If you had a budget for one human mission, or a dozen new robots every two years, which one would you consider more beneficial?
> In reality the first man on Mars will likely discover far more in a week than we have in more than 50 years of probes
Robots will make a lot more progress in the next decades than humans will.
Also, it if takes us 50 years to send humans to Mars vs sending a constant stream of improving robots now, then robots win.
I’m not an AGI believer, but I think the time horizon for AGI robots on Mars might actually be shorter than the one for humans on Mars.
The budget and general public interest will be 1000x greater if humans are sent.
“Robots explore Mars” is a daily news highlight.
“First humans land on Mars” is a global historical event.
General public interest will vanish once people realize that the journey will last two years and likely start 30 years from now. Oh, and they won't see the event live anywways.
The trip to the Moon was a free trip to Jurassic Park in comparison.
Humans are extraordinary machines.
We are self-healing, regenerating, low-power, versatile, autonomous, and most of us have a pretty decent array of sensors built-in, along with some communications equipment that's capable of interpreting the signals from our sensors and transmitting that information to other humans in a remarkable variety of ways. All of these are approximate and relative of course, if someone replies with e.g., "but actually we're not as low power as...", it will be easy to ignore.
Specialized machines can do things humans can't, of course. No single human could have survived as long in the Martian environment as any of the rovers have.
But nobody has yet designed a machine that can do all the things humans can do.
Take the single problem of mobility: many very smart engineers have worked together to develop a set of wheels that can usually move the rovers around their environment without getting stuck or damaged, or at least have a chance of getting unstuck. A human that hasn't climbed a set of stairs in a decade can still outpace the rovers, and do so over more varied terrain, and with less chance of getting stuck.
So, yes, from an engineering point of view, building new robots that can do things and shipping them to Mars to do those things presents a lot of very interesting technical challenges to solve. It's all endless puzzles and little unsung feats of science and engineering -- assuming there is a country left with both the will and the resources and the talent to pursue such things.
But from a human exploration perspective -- our instinctive drive, or compulsion, or whatever it is, that has spread our species across the entire planet -- no machine will ever quite satisfy the desire to have that experience with the sensors we were born with.
My enthusiasm for a human mission to Mars has waned quite a bit in the last few years, largely owing to its most vocal advocate. Still, all the same, I think we should acknowledge that robots are poor substitutes for geologists.
I can certainly agree that humans, regarded as perfected creatures of biological engineering, would make for an extraordinary Mars rover. You can make the case that we even the best among all animals for that job here on Earth (we are that good, a fascinating convo for another thread).
The trouble is space itself is really rough in new and different ways. Even if everything is going right, the radiation is extremely dangerous, both on the journey and on Mars itself. And there's bone decalcification which happens very fast. And life support systems issues become very quickly entangled with all the other engineering issues that can cause cascading failures between systems, so even if you didn't think of (say) engineering failures of how power gets to some component as a life support issue, it can become one due to the interdependence of systems.
> Take the single problem of mobility: many very smart engineers have worked together to develop a set of wheels that can usually move the rovers around their environment without getting stuck or damaged, or at least have a chance of getting unstuck. A human that hasn't climbed a set of stairs in a decade can still outpace the rovers, and do so over more varied terrain, and with less chance of getting stuck.
Yeah, we’ve got great fine motor skills and high dexterity, but are obviously still too dumb to emulate those parts effectively.
In the spirit of xkcd 1232[1]...
What's the timeline on "exhausting all the science collection abilities of robots?" Ten years? Fifteen? There are a lot of potential future robot abilities...
[1] https://xkcd.com/1232/
Yes, well, maybe logically speaking that would be true. Practically speaking hardly anyone blinks an eye when 'society' daily sends young (mostly) men into harm's way whether that be by employing them in known dangerous professions such as logging (etc.) or by sending them to war. According to the Geneva Declaration on Armed Violence and Development, more than 526,000 people die each year because of the violence associated with armed conflict and large- and small-scale criminality [1] while the world just keeps on turning. Nobody would even blink an eye if that number changed to 525.000 per year by putting dangerous criminals behind bars and keeping them there or by eradicating some terrorist group somewhere nor would they loose sleep if it changed to 527.000 per year after some conflict somewhere flared up again. Life is not as precious as it is often thought to be by most of us here on this site. Seen in that light it makes a lot of sense to choose 1000 volunteers out of the millions who would show up if asked to go on a mission to Mars, success not at all guaranteed and quite likely to be a one-way trip for the foreseeable future. Mars has been explored by a multitude of probes and rovers so sending the next one, no matter how advanced, will not cause much of a stir. Sending 1000 people to Mars with the intent of establishing an outpost will 'rock the world'. If successful (which is not at all a given) it would be one of the greatest achievements of our species while a successful robot mission would just be another tick on the list.
[1] https://databank.worldbank.org/metadataglossary/world-develo...
>Life is not as precious as it is often thought to be by most of us here on this site
starting anything by throwing out the value human life seems like a bad direction.
I think the person you're responding to had a solid point, but he derailed it with his own examples. It's not about "throwing out the value of human life" but appreciating that risk is something that, in many endeavors, is going to remain relatively high even if you make every effort to minimize it.
When we went to the Moon, the obituary for the astronauts was written before they even took off. And the astronauts themselves felt they had somewhere from a 50% to 70% chance of success. Everybody was well aware of the extreme risks, but they still voluntarily participated, because they felt the achievement was worth the risk. And indeed those brave men inspired an entire generation to science and achieved what many believe was still the greatest achievement in humanity's entire history.
The first missions to Mars will always be high risk, because the fundamental issue is that you're always going to be doing a bunch of things that no other human ever has. There's just so many unknown unknowns there that we're going end up getting surprised by something. So all we can do is make sure we have highly capable people and try to prepare as well as we can. But in the end, even when you work to minimize risk as much as you possibly can, that mission will always qualify as 'risky.'
Conversely humans are absurdly bad at statistics - i.e. "an astronaut feels he has a 50 to 70% chance of success"...isn't a real prediction. It isn't based on any failure analysis.
The actual failure analysis and engineering was substantially more confident, because otherwise why go? 50% is a coin-flip, but those odds were already proven wrong by the missions before Apollo 11 anyway (since there was more then 1).
You're doing some improv here based on your intuition when history has a way of surprising us. So what was the "actual" failure analysis and risk percent? It didn't exist. "Mathematical risk analysis was used in Apollo, but it gave unacceptably pessimistic results and was discontinued." [1]
Of course there were working assessments internally and they generally put the figure at about 50%. That figure is from Gene Krantz's excellent book "Failure Is Not an Option." The reason you go is because you cannot find any other practical way to significantly reduce the risk, and are willing to accept the risk you end up with.
Also I feel you're somewhat denigrating the astronauts with your comment by saying their estimations weren't "real". These weren't just adrenaline junkies looking for a wild ride - they were extreme intellectual outliers with higher degrees in aerospace engineering and extensive backgrounds in the development and application/flight of all sorts of aerospace systems. Like that paper also mentions, "The only possible explanation for the astonishing success [of the Apollo Program] – no losses in space and on time – was that every participant at every level in every area far exceeded the norm of human capabilities."
[1] - https://ntrs.nasa.gov/api/citations/20190002249/downloads/20...
"Many of them will die, but that's a sacrifice I'm willing to make".
You show a Hollywood quote, I'll raise you a better one:
Space: the final frontier. These are the continuing voyages of the starship Enterprise. Their ongoing mission: to explore strange new worlds; to seek out new lifeforms and new civilizations; to boldly go where no man has gone before
You missed the 'volunteer' part it seems. People have volunteered for expeditions with uncertain outcomes since, well, forever. Some people do their utmost best to tempt fate by climbing skyscrapers and masts without any safety devices, they jump off cliffs in clothing which gives them a slight advantage over gravity, they get into devices which are supposed to keep them alive at depths which would crush them to ¼ of their size if they were to be exposed and more. People used to embark on sailing vessels to trek to unknown places, a practice which started when sailing vessels became a thing. People want to explore frontiers and some people are willing to take great risk to be among the first to do so.
No silly quote from a Hollywood production will keep them from following their drive to boldly go where no man has gone before. Or woman, for that matter.
If that's the case then what is the point?
If you think robots should do everything then you might as well retire the human race. Why even bother to live. Why explore the stars when you can get a robot to do it for you?
If the goal is "put man on Mars" then that's what you gotta do. It's harder to make the argument that you need to do that in the service of science, or even offworld colonies, given the unsuitability and impracticality of those both.
What plausible path is there to offworld colonies without sending humans?
If the end game is offworld colonies, then we should craft the whole adventure as a series of one-way trips, not two-way trips.
That's a serious paradigm shift compared to what this (excellent) article describes.
Colonies on Mars are what drove the founding of SpaceX. Elon was looking up NASA's plans about sending humans to Mars and found that they simply didn't exist. He wanted to send a greenhouse to Mars while streaming its growth to get people inspired and thinking big again. NASA wasn't interested, Russia wanted too much $$$, so SpaceX was born. A colony doesn't mean you live there forever - it simply means a permanent human establishment. Some people will want to go back to Earth, some will want to stay on Mars indefinitely.
This is a big part of their obsession with lowering costs to space. When the launch costs are not such a huge economic factor, you have much greater leverage with doing things like building, resupplying, or even engaging in interplanetary commerce.
My understanding is that what drove the founding of SpaceX was a promise for more efficient use of agencies' money in space programs.
Going to Mars may have been part of the story, but I doubt that it was a strong component of the decision making in the end.
His main motivation was about making humanity a multiplanetary species, largely as a means of ensuring humanity's continuation. It sounds hyperbolic, but Earth has gone through multiple mass extinction events and we're rather overdue for another. And while those mass extinction events were all natural, there's also endless ways you can imagine us all managing to kill ourselves off. And, critically, all of these hyperbolic scenarios will seem extremely improbable up to the very day that one does inevitably happen. So the best time to start would be 50 years ago. But the second best time would be right now.
So the most logical place to start for this sort of 'humanity guarantee' would be Mars, which shares an oddly large amount in common with Earth. There's a verbose (and rather entertaining read) with lots of first party commentary here. [1]
[1] - https://waitbutwhy.com/2015/05/elon-musk-introduction.html
This has been covered before but saying that Mars would be a “humanity guarantee” is actually extremely illogical, not the most logical. Short of the Earth getting blasted to tiny pieces in some way there is no scenario where Mars is more habitable than Earth. This is the sort of sci-fi Utopianism that this sober article is standing in opposition to. Mars may be the second most habitable place in the solar system and it’s infinitely less habitable than a nuked-out fallout-ridden earth or an overheated green house earth. There is no magic scenario where Mars suddenly ends up with a magnetosphere and an atmosphere.
The whole "let's by insurance for humankind" story is totally valid in my opinion.
This article is however very useful to bring pragmatism to the discussion.
Maybe the best insurance for humankind is to start shipping a continuous stream of robots to Mars to prepare human landing in many (many) years.
We could buy insurance for humankind underground here on Earth much sooner and much cheaper. Plus that could kick start post human Eloi so win win.
This logic does not necessitate Mars ever being more habitable than Earth. Imagine one of the countless doomsday scenarios - a large asteroid impact. What kills you is not necessarily the asteroid, but it flinging debris into the sky that blots out the sun, not only creating a massive cold, but also rapidly killing all plants which starts a rapid series of extinction events on up the food chain.
If that happened Earth itself would still, even during the extinction event, be a dramatically more pleasant place than Mars. But nonetheless that event would kill off the overwhelming majority of people on Earth, and very possibly 100%, because it's such a significant change from the status quo we expect to continue on Earth. But having a parallel society or societies would ensure that even in the 100% scenario, life could get back up and organized relatively quickly. And even in the "only" 99% of people killed scenario, the outside help could help to reestablish order and kickstart society.
You could build a better 'colony' on earth to survive that event for way less money/effort/risk than a colony on mars. You aren't going to have a colony on Mars contributing back to the home planet in any meaningful way, and 1% of people left on Earth is still 80,000,000, many more than will be in a Mars colony.
Building colonies in-planet that could survive all possible scenarios would probably be impossible. But even if it were you'd face a pretty simple problem - who would ever want to live for there? You'd likely end up living in conditions that would make life on Mars look pleasant, without any of the upsides that might take people to Mars - adventure, ideology, commercial aspirations, perhaps even religious (you know the Mormons will want a planet or two), and of course 0.3g!
And who knows what the future holds in terms of population sizes? I also strongly disagree on the colonies not being able to engage in exchange. For a silly but very practical example sports in 0.3g are going to be insane. Jordan could jump something like 11ft and stay airborn for several seconds on Mars. That's going to be just be stupidly awesome to watch and play. MMA will look like a something out of a Chinese martial arts movie. For more mundane things, as the price of shipping cargo decreases the number of things available for trade increases. For example wine made in 0.3g will taste very different. Whether that's better or worse is yet to be discovered, but obviously such ideas will have no difficulty finding a market.
For better or for worse Mars (or the Moon) will also probably make amazing retirement places, especially if we can work on the scenery a bit. Taking that load of old bones might not only provide comfort but even increase longevity enabling a weaker heart to keep pumping a bit longer. And so on endlessly.
For me first logical step is to ignore the getting there part. And prove that we can actually build colony here. In suitable location say for example Sahara or Antarctica. After those technological challenges are solved next step is to see how to get it to orbit or make same in orbit. And then we can start thinking how to get all the stuff over there.
I agree. That was the sense of my comment too.
There's not really a plausible path to colonies on other planets (or on moons of Jupiter or Saturn) that needs to send humans there soon. Establishing such a colony and getting it working well enough to actually last would be a long term project, and it would be decades before it got to sending people.
Before that there would be a lot of work off Earth, including manned work, but it would be in space or on the Moon.
They key is Lagrange points. Each pair of bodies (Sun/Earth, Earth/Moon, Sun/Jupiter, etc) have 5 points where the gravitational forces from the two bodies balance out in a way that makes it possible for something to orbit that point, even though there is no massive body at that point.
Two of the Lagrange points are stable, meaning that if something in orbit around them is disturbed it still stays around that point. The other three are unstable. Disturbing something there will cause it to get farther and farther away.
You can use this to move things from Lagrange points of one pair (Sun/Earth for example) to Lagrange points of another pair (Sun/Jupiter say) very cheaply. Get it to the starting point, and then nudge it into an unstable orbit that will have it getting farther and farther away. We can calculate these unstable orbits well enough to pick one that at some point is nearly tangent to an orbit of the destination Lagrange point that moves toward that point rather than away. A little nudge them can move our ship into that latter orbit.
The catch is that this is slow. It might take decades or more to make the trip.
The way you would use this in a colonization program is to build a series of unmanned cargo ships. Say a new cargo ship is completed every year. It would be stuffed full of supplies the colony will need, send to an appropriate Sun/Earth Lagrange point, and nudged onto its journey.
Let's say these ships take 30 years to reach the destination. After we've been doing this for nearly 30 years then we'd send a ship with the colonists. That ship uses a fast but expensive orbit. It would only need to carry the colonists, the supplies they need during the trip, and fuel and supplies for an emergency return trip in case when they get there they find some reason that they cannot stay.
Note that it doesn't need to carry any material to actually build the colony, or food and water for the colony. All that is in the cargo ships that are now arriving yearly. (If we are sure that the cargo ships are making it the human transport ship could even omit food, water, and fuel for an emergency return. Those can be on the first cargo ship).
You'd want to build the cargo ships on the Moon, or build them in space using resources from the Moon, because getting from the Moon to Lagrange points takes a lot less energy than getting from the Moon to Lagrange points.
The most plausible path then is to greatly expand industrialization of the Moon and the space near Earth. Probably then expand that to include space bases at some of the Lagrange points.
Then it is time to start working on colonization.
Unfortunately we'd probably not do Mars this way. If I recall correctly the low energy Lagrange transfer orbits to Mars are particularly slow--over a thousand years if I remember correctly.
Hah! I wrote my comment sort of quickly and I knew someone would pick that out!
Don't miss part 1 (2023) for context.
https://idlewords.com/2023/1/why_not_mars.htm
Seems like the most conservative approach would be to send the return vehicle first, empty. Once it's landed safely on Mars and all systems look good, it would be reasonable to send the human crew in a 2nd vehicle?
I had the same thought, but this has no effect on necessary delta-V. In terms of risk, I suspect it's already baked in to his analysis at some level. The risk comes from human-time-on-planet or time-in-space, which having a return vehicle doesn't change.
An interesting and fun read along these lines that examines many aspects of colonizing Mars, is A City On Mars, by the Weinersmiths
Unfortunately, in spite of a lot of good material in it, it’s also deeply flawed.
How so?
Would love to see a (robotic) sample return mission, pick up some of the piles of specimens from one of the rovers.
Sounds potentially horrific to test with humans:
> able to communicate home by radio, but forced by unalterable cycles of nature to wait months or years for a rescue ship.
Eh, we've done it before. Read up on Magellan's circumnavigation, the colonization of Australia or the Shackleton era of Antarctic exploration.
Of course, the difference is that compared to the conditions that await on Mars, a roaring blizzard on Antarctica is a balmy spring day. The air may be cold but at least it's breathable.
I'm picturing that the safe way forward is to send a 1000 day duration mission to LEO which would remain autonomous except in case of critical failure. Probably a series of them.
a variable not covered: mental well being on the long voyage.
Aluminum is a poor material choice for thick radiation shielding, since it produces lots of secondary radiation and it's inefficient due to its high atomic mass. Polyethylene, which is nice and hydrogen-rich, is widely understood to be superior.
An aluminum hull is nice because it does double duty, but you don't need to make it thicker than the structure requires just for radiation purposes. Instead you would add internal shielding. It's also smart to use food (and the resulting waste) and other consumables as shielding, since you need to carry that mass anyway.
I think you misunderstood a diagram; grams of Al per square centimeter is a standardized unit of shielding in the literature, not an engineering choice.
That doesn't matter though. Since it's not representative of the real shielding, it's an inapplicable standard to use for this problem.
You should realize that there's no simple way to convert from aluminum to polyethylene: it's not as simple as "PE is X times better." Due to secondaries aluminum stops improving after 30 g/cm^2,[1] hence why their chart (bottom line) levels out. PE doesn't have that problem, and lower dose rates are achievable versus what the author states.
TL;DR regardless of if you call it a "standard" or not, the author is still using bad math to overstate the actual risk.
[1] Figure 3, solid black line https://ntrs.nasa.gov/api/citations/20170005580/downloads/20...
I didn't choose AL shielding as the reference standard to use in the literature; I'm sorry it bugs you.
You can read the author's other work, that goes into great detail about different types of shielding, if you want to gain confidence in his math. The upshot is you need many meters of polyethylene to effectively shield the heavy ion component of GCR, which is what the fuss is about.
But the point of that particular diagram is not shielding, but to illustrate the 2-3x uncertainty in estimates of tumor risk based on our poor understanding of high-Z ion exposure.
Water is a big one. Missions to Mars will be carrying tons of it, and it's an absolutely excellent radiation shield.
The author puts a Mars mission into a realistic perspective but also, I think there are people who are wired differently than they are.
I'm not a test pilot but I'm a licensed pilot and I'd sign up for a Mars mission in a heartbeat, even if there was a 70% chance of success.
We send people under the ocean for years at a time to live on nuclear submarines in arguable more dangerous and isolated circumstances and they don't blink at the opportunity. To be the first person on another planet? What an incredible, fantastic opportunity. I feel like we will need to return to a place (As a society) where we accept risks that push the boundaries of the human race. Something we had a lot of in the 1960s but not a lot of today.
> years at a time
I don't think any single crew deployment reaches a year.
> more dangerous and isolated circumstances
I think Mars is massively more dangerous and isolated. A submarine can plausibly return to port or surface to breathable air. There is no such option on Mars. Nuclear submarines are much larger than spacecraft and have much more room for comfort options. They have a much larger crew, and the knowledge that this happens all the time from many nations must be of some comfort.
IIRC British antarctic service does uninterrupted 2 yer contracts. Not Mars or a submarine but still 2 years.
At least being outside doesn't kill you in those ones.
There's also earthbound experiments like Nasa's CHAPEA programs (https://www.nasa.gov/news-release/martians-wanted-nasa-opens...) but they only go up to about a year.
> I'd sign up for a Mars mission in a heartbeat, even if there was a 70% chance of success.
I am pretty sure that your confident self would think a few times before signing the NASA paperwork with this number.
It wasn't about pushing boundaries, it was about beating the USSR.
“ We send people under the ocean for years at a time to live on nuclear submarines in arguable more dangerous and isolated circumstance”
Mars is by orders of magnitude worse than living on a submarine.
> arguable more dangerous and isolated circumstances
I guess technically anything is arguable, but this seems absurd. Sure there's pressure and cold, but a submarine can hold 100+ people and surface in 10 minutes.
Mars is 10 months away with maybe 10 people. There's no surface. You can't scrub oxygen from the water, hell there's almost no water at all. You won't be crushed by pressure but you'll be bombarded by radiation.
[dead]
I reluctantly upvoted this for the wealth of scientific/engineering knowledge it contains despite strongly disagreeing with some of its conclusions:
--
In recent years, there’s been a remarkable division in space exploration. On one side of the divide are missions like Curiosity, James Webb, Gaia, or Euclid that are making new discoveries by the day. These projects have clearly defined goals and a formidable record of discovery.
On the other side, there is the International Space Station and the now twenty-year old effort to return Americans to the moon. These projects have no purpose other than perpetuating a human presence in space, and they eat through half the country’s space budget with nothing to show for it. Forget even Mars—we are further from landing on the Moon today than we were in 1965.
In going to Mars, we have a choice about which side of this ledger to be on. We can go aggressively explore the planet with robots, benefiting from an ongoing revolution in automation and software to launch ever more capable missions to the places most likely to harbor life.
Or we can stay on the treadmill we’ve been on for forty years, slowly building up the capacity to land human beings on the safest possible piece of Martian real estate, where they will leave behind a plaque and a flag. But we can’t do both.
--
1. SpaceX/Starship lower the cost of human space exploration by possibly two orders of magnitude over the Apollo/Space-Shuttle era
2. We can increase the amount of resources allocated to space exploration.
For both of these reasons, we absolutely can pursue both tracks.
I remained neutral on it since I also thought it was an interesting and clearly well researched article, but I think it leaned a bit too heavily on some somewhat inappropriate analogs to things like like with the ISS. It's a deteriorating old station where astronauts need to constantly prepare for orbital reboosts, receiving cargo, running commercial experiments, literally plugging holes more recently, and so on. This doesn't really translate meaningfully to the responsibilities on an interplanetary mission on new hardware.
Similarly alot of his stuff about microgravity just handwaves away the fact that a lot of the mission will be spent in 0.3g. And, in terms of overall effects on the body 0.3g will almost certainly end up being closer to 1g than 0g. It'll make it much easier to do things like exercise and all the "normal" physics of things would be much closer to the environment we all evolved in, than in 0g where everything just gets super funky. In fact I wonder about the viability of simply wearing body weights while on Mars, something that obviously would not work in 0g.
The radiation stuff has also been pretty well researched and isn't likely to be a show-stopper, especially with normal measures for protection like using the water supplies as a shield.
> overall effects on the body 0.3g will almost certainly end up being closer to 1g than 0g
But what do you base this on? Vibes? Because the article correctly points out that:
> This goes against our intuitions, but there have been bigger surprises in space.
Most of the major negative effects from time in 0g are pretty easy to derive from first principles - like the loss of bone density and muscle mass. The cause is simply a lack of muscular exertion. In 0g you don't really have much of any recourse against this except lots of mostly elastic based exercise, so astronauts on the ISS spend 2+ hours every single day just exercising, and it still isn't enough. On Mars the deterioration will obviously be lesser. And you also have much easier solutions not only in terms of working out but also passive, like the proposed body suits.
Also I'd add that even the less well understood issue like vision decline generally has to do with things 'not going the right way' -- in this specific case 'stuff not going down' increasing the pressure on your ocular region (ever noticed how astronauts all seem to have kind of bloated heads while on the ISS?). On Mars (or any other body with some reasonable degree of gravity) these sort of things won't be a problem.
Good point, we don't have to exactly follow the "astronauts in a small tin can, where everything must work flawlessly" way. With Starship (or its future iteration/successor) we can:
- assemble a quite large interplanetary craft in orbit, with plenty of redundancy in HW and supplies
- drop 50 tons of cargo on Mars beforehand: food (and/or food-growing necessities - packaged soil, hydroponic equipment?), medical supplies, etc.; so that in case of problems, astronauts can survive on Mars for years if need be
napkin for ion drive powered by solar - tech available today (and nuclear as the power source for the ion drive instead of the solar - tomorrow for Mars and beyond) - looks much better than chemical even for Mars. As SpaceX already using ion drives on Starlinks, and the SpaceX will be the one going to Mars, i'd expect that it will be ion drive.
Solar electric propulsion has great specific impulse [i.e., efficient use of propellant] but very low thrust. You're forever spiraling away from and then down into gravity wells.
It's terrific for cargo, but not viable for crews.
I expect the best way to use ion thrusters would be to combine them with chemical engines.
Use chemical engines for the high thrust trans-Mars injection burn so you can exploit the Oberth effect, then use ion thrust to continuously accelerate the ship for a (modest but still helpful) reduction in travel time.
https://en.wikipedia.org/wiki/Oberth_effect
not forever. You can get to Mars faster than with chemical, something under 90 days one way in some reasonable configurations.
What does that look like? A ten ton ship including 100 square miles of solar panels?
You need about 10KWt per 100kg, i.e. 50m2 of panels. For 10 tons it would be under 5000m2, ie. like 70x70m. The panels do need to be relatively thin. Less than half the mass - 4 tons is the expelled mass (using say those NASA drives with 3500 Isp). And if you get panels at 0.5kg/m2, you'd get to 15km/s in under 2 months with about 3.5 tons for the rest of the ship including payload. More panels - either thinner ones or with less payload - faster time to Mars. Nuclear with ion drive - even better (and the only choice beyond Mars), can get you 35km/s+ (Voyager) or like 70km/s+ with 2 stages in under year.
> Nuclear with ion drive - even better (and the only choice beyond Mars)
I'm sure you'll be interested in this concept.
https://iopscience.iop.org/article/10.1088/1538-3873/ac4812
And this related one.
https://www.frontiersin.org/journals/space-technologies/arti...
i'd say i hope for the hybrid - nuclear (especially fusion once we get to it) generates power while something like in your second link collects the mass for expelling from the drive. The nuclear can work far beyond Solar system while the running out of the expelling mass is the main limiting factor here.
You've definitely missed some decimals somewhere and/or are not considering the amount of thrusters needed. Ion thrusters total thrust is measured in the millinewtons and they have a very poor thrust:weight ratio (which does not account for the energy source mass). They're also relatively unreliable making them generally unfit for round trip missions without excessive redundancy which further increases the mass and thus the number of thrusters needed. Almost like a sort of microcosm of the tyranny of the rocket equation.
7KW NASA drive weight about 10kg. At 10KW it would expel about 8milligram/second for 0.3N thrust (even with paltry 50% efficiency). It will get ship of 100kg total starting mass to 15km/s in under 2 months spending under 40kg expelled mass. The arithmetic is very simple. (my favorite arithmetic here is 3 stage nuclear powered ion drive ship with increased voltage resulting in ~35000 Isp and thus getting 1000-1500km/s in 100 years, and thus 1000 years fly-by to Alpha Centauri, with the tech basically available today :)
>They're also relatively unreliable
Given their simplicity i think it is among the most reliable pieces of tech around. 5 years non-stop - no issues :
https://www1.grc.nasa.gov/space/sep/gridded-ion-thrusters-ne...
Note that all this is just NASA so far without SpaceX/Musk applying their engineering magic yet which i think would significantly improve the mass, efficiency, etc.
Mass = 10,000kg (per the initial topic)
Force = 0.236N (per your link)
Acceleration = 0.0000236m/s (acceleration = force / mass)
Seconds in 2 months = 5259600
Final Velocity after 2 months = 277 miles per hour (0.124km/s)
---
This is an extremely naive and optimistic calculation since I'm assuming the engine is weightless and does not require fuel or power. It's easier that way and still emphasizes the point perfectly fine. You're gonna need a lot more engines to get anywhere. And of course a 10 ton ship is not practical. The goal for Starship is to to have a payload in the hundreds of tons, let alone the entire vessel's mass.
You also only have half the distance to accelerate, because you then need to turn around and decelerate the remaining distance. And we're also ignoring landing/takeoff which obviously isn't happening.
>Mass = 10,000kg (per the initial topic)
>Force = 0.236N (per your link)
>I'm assuming the engine is weightless and does not require fuel or power.
10KW 10kg engine plus 40 kg expelled mass per 100kg total starting mass. Thus for 10000kg - 1000kg of 100 x 10kg 10KW engines, 4 tons expelled mass, 2.5 tons - solar panels providing power. 1 engine - 0.3N, 100 engines - 30N. 15km/s in under 2 months, plus 2 months deceleration. The same for 100ton ship or 1000ton.
>landing/takeoff
that is by local chemical Starships "shuttles" which would transfer people and cargo to/from the interplanetary ships. Using Starship shuttles to fuel the interplanetary Starship, though chemical one, has long been in the published SpaceX/Musk plans.
?????? You definitely gotta try to explain that one
Has there been discussions on who to send on a "man"ned mission? Apollo had height and weight limitations for an average male, and now that DEI is dead, I wonder if it's more prudent to proritize sending smaller people (really light women) because sexual dimorphism seems to be a thing in the military.
Women tend to be substantially more susceptible to radiation related issues. [1] In reality though I think the main issue (outside of competence/merit) will be making sure people stay psychologically sound being tens of millions of miles away from Earth, for years. So in that case I wouldn't be surprised if they end up prioritizing highly capable couples.
[1] - https://pmc.ncbi.nlm.nih.gov/articles/PMC6509159/
I think if long term supplies bottleneck, one would pick for physiology that requires less, i.e. 100lb person consumes ~50-60% calories as 200lb person. Or for same supplies you get much more brains/work done. Light lesbians with no need to worry about pregnacy fits the bill.
I'm no psychologist but sending couples is a really bad idea. It's a mission, not a Big Brother style relationship test.
If they do intend to send couples, put them in a small room for a year first as part of their training and selection process.