The Shape of a Mars Mission
https://idlewords.com/2025/02/the_shape_of_a_mars_mission.htmIt 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.
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).
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-...
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.
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.
Had we maintained the political will though there's no real reason we wouldn't have had a colony on Mars decades ago.
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…
Not to mention launching to Mars from the moon is easier (in some respects, not all).
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.
It just doesn't make sense to me to send humans. Exhaust the science collection of robots first.
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.
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.
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.
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...
https://www.investmets.com/nasa-workshops-aim-to-merge-on-an...
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.
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)
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.
If you had a budget for one human mission, or a dozen new robots every two years, which one would you consider more beneficial?
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.
“Robots explore Mars” is a daily news highlight.
“First humans land on Mars” is a global historical event.
Also, we didn't "send" them, the early explorers and bases were done by people who wanted to go and do research there. We have lots of people who want to go to Mars to do research or who want very much to benefit from the research humans can do better on Mars than current robots.
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.
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://databank.worldbank.org/metadataglossary/world-develo...
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?