Well - basic assumption behind your question is that we are going into space to colonize. Certainly Nasa so far is most focused on finding out about the solar system, not colonizing.
And - are many practical reasons why it really makes no sense to send humans to Mars to colonize. Even after an asteroid impact + global nuclear war, Earth would be far more habitable than Mars and the best place to colonize in the solar system, and to terraform. And - much of the surface of Earth is not inhabited - all the sea floor or floating on the sea - many of the mountain ranges - the vast deserts, Antarctica - all those places are far far more habitable than Mars or anywhere else in the solar system. So why spend billions of pounds to send humans to Mars? Makes no sense to me if aim is to colonize, while if aim is to explore it does make sense.
But if aim is to explore - then you don't want to go to the surface. Because
Used to be thought that a human expedition on the surface wouldn't contaminate it because it's so hostile nothing could live on the surface. But there are many lines of evidence suggesting that's not the case. Especially the "warm seasonal flows" dark strips in the equatorial regions, which only form when temperatures go above 0C in sun facing slopes and not correlated with winds and lengthen with season. And DLR evidence that some microbes here on Earth may be able to survive on Mars surface as is, just using night time humidity of the atmosphere - and the work on deliquescing salts identified by Phoenix that may well provide habitats a cm or so below the soil surface.
So especially also since human missions to the surface risk crashing, there's a severe planetary protection issue to be addressed as well.
Not sure how much of this NASA has as its motivation. May be in two minds there - some scientists like Robert Zubrin encouraging them to colonize as quickly as possible - with others saying that it is not a good idea to colonize at all at this stage. and others somewhat in between the two. But it would be hard to get COSPAR approval for a human mission to the surface right now I'd think also - don't see how they could approve a mission with a risk of a hard landing leading to dead humans on the surface of Mars.
Of course not that I'd want that to happen but it is a risk that the astronauts would take, knowingly - and probably e.g. far more risky than base jumping to go on a human mission to the Mars surface, just because of the possibility of crashing. And - they would be risking the future of Mars an entire planet and all benefits that might flow to humanity from discoveries made on Mars - not just their own lives that's the thing.
It's a decision for the whole world to make, not just a few astronauts who may be willing to risk their lives - but what about the consequences for everyone else.
Anyway I've written lots of articles about this you might like:
And - are many practical reasons why it really makes no sense to send humans to Mars to colonize. Even after an asteroid impact + global nuclear war, Earth would be far more habitable than Mars and the best place to colonize in the solar system, and to terraform. And - much of the surface of Earth is not inhabited - all the sea floor or floating on the sea - many of the mountain ranges - the vast deserts, Antarctica - all those places are far far more habitable than Mars or anywhere else in the solar system. So why spend billions of pounds to send humans to Mars? Makes no sense to me if aim is to colonize, while if aim is to explore it does make sense.
But if aim is to explore - then you don't want to go to the surface. Because
- Surface is a dangerous place to go to. Mars doesn't have enough atmoshere for a parachute landing - but has enough to slow you down so much you can't just fly back up to orbit in case of something wrong as for Apollo. It's the most dangerous place to land in our inner solar system and in past about half of all missions to the surface have crashed and the Curiosity landing was by no means a forgone conclusion that it would succeed!
- Humans are clumsy in spacesuits, and it's not at all clear that they would be more dextrous than telerobots operated from orbit.
- Humans on the surface need many tons of life support, while robots do not. Robots can be lighter, and indeed even micro-robot in size and fly - on very little fuel. Humans need to carry life support with them wherever they go
- Robots can be designed for Mars, so are at home there. Humans not at all, they need spacesuits
- But most important of all, robots can be sterilized. Higher plants can be also (sterilize the seeds). But humans and animals and insects can't be. We have trillions of microbes in many thousands of species, many not well understood.
Used to be thought that a human expedition on the surface wouldn't contaminate it because it's so hostile nothing could live on the surface. But there are many lines of evidence suggesting that's not the case. Especially the "warm seasonal flows" dark strips in the equatorial regions, which only form when temperatures go above 0C in sun facing slopes and not correlated with winds and lengthen with season. And DLR evidence that some microbes here on Earth may be able to survive on Mars surface as is, just using night time humidity of the atmosphere - and the work on deliquescing salts identified by Phoenix that may well provide habitats a cm or so below the soil surface.
So especially also since human missions to the surface risk crashing, there's a severe planetary protection issue to be addressed as well.
Not sure how much of this NASA has as its motivation. May be in two minds there - some scientists like Robert Zubrin encouraging them to colonize as quickly as possible - with others saying that it is not a good idea to colonize at all at this stage. and others somewhat in between the two. But it would be hard to get COSPAR approval for a human mission to the surface right now I'd think also - don't see how they could approve a mission with a risk of a hard landing leading to dead humans on the surface of Mars.
Of course not that I'd want that to happen but it is a risk that the astronauts would take, knowingly - and probably e.g. far more risky than base jumping to go on a human mission to the Mars surface, just because of the possibility of crashing. And - they would be risking the future of Mars an entire planet and all benefits that might flow to humanity from discoveries made on Mars - not just their own lives that's the thing.
It's a decision for the whole world to make, not just a few astronauts who may be willing to risk their lives - but what about the consequences for everyone else.
Anyway I've written lots of articles about this you might like:
- Why Elon Musk's Colony on Mars in 2020s is Unfeasible - What Could We Do - Really?
- No Escape From Problems in Space Colonies - Earth is Des Res - Even After Nuclear War or Asteroid Impact
- Why Mars is NOT a Great Place to Live - Amazing to Explore From Orbit - with RC Rovers, and Nature Inspired Avatars
- To Terraform Mars with Present Technology - Far into Realms of Magical Thinking - Opinion Piece
- Trouble With Terraforming Mars
- "Ten Reasons Not To Live On Mars, Great Place To Explore" - On The Space Show
- Telerobotic Avatars On Mars With Super-Powers ("Teleporting" from orbit) - Search For Life - And Long Term Exploitation
- Ten Reasons NOT To Live On Mars - Great Place To Explore
- How Valuable is Pristine Mars for Humanity - Opinion Piece?
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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