The bit of mars that fascinates me is the Hellis Planitia[1] A huge hole roughly opposite the globe from the large volcano complex[2] coincidence.. I think not.
I am vaguely surprised it was not higher rated for a rover mission. 7k meters down should do something interesting to the atmosphere if nothing else.
Yeah it's the one place that crosses the triple point of water, not by a huge margin, but likely enough to trigger planetary protection concern.
But there's places like the araneiform terrain where you likely get much higher transient pressures, and maybe they create enough of a greenhouse effect to warm up before they burst through the CO2 ice crust. They'd be a great way for life to spread mechanically using those pressurized bursts.
Sounds like the Martian mantle is (or was) organized as a single giant convection cell, with the upwelling under the volcanoes and sinking at Hellis Planitia.
Effects of 7km upon the atmosphere seem easily predictable. Ditto the benefits of 7km for exploration - improved aerobraking, drone performance, etc. But not so predictable would be effects on the subsurface.
An obvious downside of 7km would be "better" air cooling of equipment that needs to stay warm during Martian nights.
I really hope we'll see humans on Mars in my lifetime. For all the amazing success that rovers had, starting with Spirit and Opportunity, and now with Curiosity and Perseverence, having a bloke with a shovel can likely be more productive in a few days than years of missions combined...
Our existing method of moving between planets (heck, even the Earth & Moon) will take 9 months to get from Earth to Mars (or back). And the launch window is every 22 months. The return to Earth is either 4 weeks after you get to Mars, or 23 months later (so any fault that prevents a prompt return means you better have almost 3 years of food/water/air onboard).
Without some magical SF technology being invented, no, we're not going to see humans travelling to Mars in our lifetimes.
If folks are serious about human trips to Mars, there would be an effort to send supply ships ahead of time and stockpiling fuel/food/water/air in orbit around Mars. This would solve 2½ problems:
1 - Carrying supplies for both directions would require building spaceships bigger than we can currently build.
2 - If there is any failure on the way or at Mars, there will be stuff to let the astronauts survive until they can fix things or any sort of rescue mission could be sent.
And "that half" - Currently, the US has had a 70% success rate sending stuff to Mars (the Soviets had 50% success). Some of those supply ships won't reach Mars orbit. Some will break on the way there and drift past Mars. Some will smash into the surface of Mars.
Why send stuff? Supplying the astronauts on ISS requires sending 1000 pounds of stuff per person per month. And that's only 300 miles from Earth. And the ISS has water recycling, yet they still need water sent up.
My estimates for a successful "manned" trip to Mars (and return them safely to Earth again) would start around $200 billion.
The recent findings about the dust being so fine it can penetrate the blood-brain barrier is a real concern though. The more we learn about the planet, the more it sounds pretty unsuitable for habitation.
The cosmic radiation alone poses a major problem, let alone the logistics of supplying water/air/food. I am much more optimistic for a research outpost on Luna.
Though the person you commented on didn't refer to habitation specifically I think, just humans on the surface.
I tend to agree with your thoughts on the moon. Realistically we should be looking at orbital manufacturing and refuelling in our local neighbourhood first and use Luna as a staging area for any deeper missions, of which I feel there's far more interesting features to look at (i.e. Titan, Europa etc)
I don't really think so. To start with there's a lot of really interesting concepts in terms of habitation for Mars. For instance the water/air stuff is oddly enough solved simultaneously, alongside fuel. The Sabatier Reaction [1] and various other characteristics of Mars really make it all feel like a video game where Mars is just clearly level 2. The reaction itself is CO2 + hydrogen = methane + water.
Since Mars atmosphere is 95% CO2 you're pretty much good to go there with a moderate supply of hydrogen. And conveniently enough electrolysis of water yields of course hydrogen and oxygen. And water is shockingly widely available on Mars given the regolith is 2-5% water by volume (giving the unit bastardization of 1 cubic foot of regolith = 1+ liter of water).
Most of the issues people are concerned about like radiation aren't, in reality, that big a deal. I say 'in reality' to mean that the radiation isn't enough to just give you immediate radiation sickness, so the real effect will be a probably reduced life expectancy due to greater rates of radiation. Even that isn't so clear for reason outside the scope of this post, but it's not a show stopper in any case. In general early colonists will have a significantly reduce life expectancy - it's just the nature of colonization, and always has been.
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Beyond that the Moon is a nightmare. Relatively minimal resources, 2 week long days/nights that vary between way beyond boiling hot and something close to absolute zero. No atmosphere at all so no protection against meteorites, somewhat higher radiation than Mars, and so on. There's also gravity very near zero which can pose some issues with various processes (industrial/etc).
And other destinations like Europa not only have dramatically more difficult 'local settings', but also have significantly greater distances. For instance Europa is about 10x as far as Mars and a somewhat more difficult trajectory to manage. In practice you're probably looking at upwards of 5 years for a one-way trip. We probably need to level up the tech tree a few bumps before realistically looking at things like that and Mars is a good way to do that.
I doubt it. Going to Mars just to enter orbit would probably require the same (or more) delta v as landing (because of aerobraking). And then you'd still have to resupply them, and that will certainly be more expensive. Your resupply missions now have to achieve orbit, and dock. You can get much cheaper "dumb" cargo to Mars by using "old" tech developed for the first rovers (parachutes + airbags).
And even then, again there's just something about a trained geologist being there, immersed in the thing, thinking on the spot, using a shovel that just can't be matched with robots.
Then you have all the ISRU (in situ resource utilisation) that you can take advantage of on Mars vs. in orbit around Mars. There have been experiments already demonstrating obtaining useful stuff (MOXIE got oxygen). And theoretically you can also make methane, you can melt water, etc.
And it happened on the opposite side of the planet! I guess that's why it took five years to analyse the data: quake from 2021, article published last month: https://www.nature.com/articles/s41467-026-78193-6
Not an astronomer - but isn't it Really Old News that all of Mercury, Luna, and Mars are "obviously" tectonically active - because, even absent every other possible cause, they're all giant rocks, all slowly cooling, and rock shrinks as it cools?
And Mars, with giant volcanoes and credible evidence of recent* vulcanism, obviously has more options for causing quakes.
I am vaguely surprised it was not higher rated for a rover mission. 7k meters down should do something interesting to the atmosphere if nothing else.
1. https://trek.nasa.gov/mars/#v=0.1&x=72.07800218650755&y=-42....
2. https://trek.nasa.gov/mars/#v=0.1&x=-116.4913302335018&y=16....
But there's places like the araneiform terrain where you likely get much higher transient pressures, and maybe they create enough of a greenhouse effect to warm up before they burst through the CO2 ice crust. They'd be a great way for life to spread mechanically using those pressurized bursts.
Sounds like the Martian mantle is (or was) organized as a single giant convection cell, with the upwelling under the volcanoes and sinking at Hellis Planitia.
Effects of 7km upon the atmosphere seem easily predictable. Ditto the benefits of 7km for exploration - improved aerobraking, drone performance, etc. But not so predictable would be effects on the subsurface.
An obvious downside of 7km would be "better" air cooling of equipment that needs to stay warm during Martian nights.
So if you can get 7km down without digging, that's the first place to look!
Our existing method of moving between planets (heck, even the Earth & Moon) will take 9 months to get from Earth to Mars (or back). And the launch window is every 22 months. The return to Earth is either 4 weeks after you get to Mars, or 23 months later (so any fault that prevents a prompt return means you better have almost 3 years of food/water/air onboard).
Without some magical SF technology being invented, no, we're not going to see humans travelling to Mars in our lifetimes.
If folks are serious about human trips to Mars, there would be an effort to send supply ships ahead of time and stockpiling fuel/food/water/air in orbit around Mars. This would solve 2½ problems:
1 - Carrying supplies for both directions would require building spaceships bigger than we can currently build.
2 - If there is any failure on the way or at Mars, there will be stuff to let the astronauts survive until they can fix things or any sort of rescue mission could be sent.
And "that half" - Currently, the US has had a 70% success rate sending stuff to Mars (the Soviets had 50% success). Some of those supply ships won't reach Mars orbit. Some will break on the way there and drift past Mars. Some will smash into the surface of Mars.
Why send stuff? Supplying the astronauts on ISS requires sending 1000 pounds of stuff per person per month. And that's only 300 miles from Earth. And the ISS has water recycling, yet they still need water sent up.
My estimates for a successful "manned" trip to Mars (and return them safely to Earth again) would start around $200 billion.
https://en.wikipedia.org/wiki/Hohmann_transfer_orbit
https://en.wikipedia.org/wiki/Launch_window
This page claims Earth/Mars launch windows are every 26 months:
https://en.wikipedia.org/wiki/Exploration_of_Mars#Launch_win...
So you are telling me we could have gone to Mars and back a few times instead..
Though the person you commented on didn't refer to habitation specifically I think, just humans on the surface.
Since Mars atmosphere is 95% CO2 you're pretty much good to go there with a moderate supply of hydrogen. And conveniently enough electrolysis of water yields of course hydrogen and oxygen. And water is shockingly widely available on Mars given the regolith is 2-5% water by volume (giving the unit bastardization of 1 cubic foot of regolith = 1+ liter of water).
Most of the issues people are concerned about like radiation aren't, in reality, that big a deal. I say 'in reality' to mean that the radiation isn't enough to just give you immediate radiation sickness, so the real effect will be a probably reduced life expectancy due to greater rates of radiation. Even that isn't so clear for reason outside the scope of this post, but it's not a show stopper in any case. In general early colonists will have a significantly reduce life expectancy - it's just the nature of colonization, and always has been.
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Beyond that the Moon is a nightmare. Relatively minimal resources, 2 week long days/nights that vary between way beyond boiling hot and something close to absolute zero. No atmosphere at all so no protection against meteorites, somewhat higher radiation than Mars, and so on. There's also gravity very near zero which can pose some issues with various processes (industrial/etc).
And other destinations like Europa not only have dramatically more difficult 'local settings', but also have significantly greater distances. For instance Europa is about 10x as far as Mars and a somewhat more difficult trajectory to manage. In practice you're probably looking at upwards of 5 years for a one-way trip. We probably need to level up the tech tree a few bumps before realistically looking at things like that and Mars is a good way to do that.
[1] - https://en.wikipedia.org/wiki/Sabatier_reaction
And even then, again there's just something about a trained geologist being there, immersed in the thing, thinking on the spot, using a shovel that just can't be matched with robots.
Then you have all the ISRU (in situ resource utilisation) that you can take advantage of on Mars vs. in orbit around Mars. There have been experiments already demonstrating obtaining useful stuff (MOXIE got oxygen). And theoretically you can also make methane, you can melt water, etc.
And Mars, with giant volcanoes and credible evidence of recent* vulcanism, obviously has more options for causing quakes.
*"Recent" in the geologic sense - https://en.wikipedia.org/wiki/Volcanism_on_Mars#Potential_cu...