In the 70s, no. Because you'd need to have at least several years experience in LEO and closer to Earth solving the problems of artificial gravity (or alternatively long term health in zero g for 2 years or more, if that's possible, which nobody knows yet) and closed system habitats.
Taking the same careful step by step approach as Apollo, then many prior missions before sending humans to Mars.
So for instance with Apollo they first demonstrated the systems worked with several missions to LEO where it is easy for astronauts to return to Earth in an emergency. Then they did a trip around the Moon and back. Then a test mission right down nearly to the surface but return to orbit. Finally landing on the Moon.
The difference from Apollo is that to demonstrate safety for a two year mission, then your precursor missions also have to be two year missions at least, and probably longer for a safety margin.
For instance, when it comes to it, I don't think that NASA would have wanted to rely on a system to send to Mars that has only been proved to work for say a few weeks or a month in LEO. It needs to be demonstrated, actually in practice, not just in theory, for at least as long in a safer location such as LEO.
That's even more important than for the Moon. In case of the Moon is a couple of days to get back to Earth in an emergency. In case of Mars it is anywhere between six months and well over two years to get back in an emergency (last would be case where the emergency happens just as you are about to return to Earth, say your return rockets fail and you need new equipment sent from Earth, then it would be two years before your next opportunity to return to Earth).
So - I am sure by example of Apollo that NASA would not send a mission to Mars without prior missions in LEO and probably to the Moon or L1 or L2 or to Near Earth Asteroids (those are more dangerous than the Moon obviously) to test the systems thoroughly in a similar live situation first.
if you did them one after another - that's 10 or 20 years worth of missions perhaps. I think myself that is still true today, if we want to be reasonably safe. And since things would surely go wrong more like 20 than 10 years.
So that would make the 90s the first time it could be done safely supposing you start work on it in the 1970s.
Must say - this is personal opinion about how long it would take - putting it out for discussion!
Anyway - it's just as well they didn't in my view because back then, at least post Viking, nearly everyone (except Gilbert Levin) thought Mars was totally sterile, in the present, and back then they thought that probably Mars never had any life (they didn't have the evidence of Noachian period oceans on Mars we have now)
While now it seems at least possible that there are habitats there potentially, even right on the surface.
Also there is indirect isotope evidence pretty conclusive that there is some water exposed to surface conditions at least episodically in geologically recent past (can't tell if it is episodic or all the time or a bit of both).
Where To Search On Mars For Droplets, & Shallow Flows Of Liquid Water - Where Microbial Life May Flourish
That needs to be resolved - if there are habitats and where they are and if there is life in them or not - before we think about landing humans there.
Indeed also even if there is no life on Mars, still there is reason for pause for thought before introducing Earth life to it - so long as there are habitats. Because the habitats are also of great interest if they don't have life - to see what happens in such habitats without the presence of life. Are there precursors of life, or complex chemical interactions happening there? No way to test such a situation on Earth.
Will We Meet ET Microbes On Mars? Why We Should Care Deeply About Them - Like Tigers
Taking the same careful step by step approach as Apollo, then many prior missions before sending humans to Mars.
So for instance with Apollo they first demonstrated the systems worked with several missions to LEO where it is easy for astronauts to return to Earth in an emergency. Then they did a trip around the Moon and back. Then a test mission right down nearly to the surface but return to orbit. Finally landing on the Moon.
The difference from Apollo is that to demonstrate safety for a two year mission, then your precursor missions also have to be two year missions at least, and probably longer for a safety margin.
For instance, when it comes to it, I don't think that NASA would have wanted to rely on a system to send to Mars that has only been proved to work for say a few weeks or a month in LEO. It needs to be demonstrated, actually in practice, not just in theory, for at least as long in a safer location such as LEO.
That's even more important than for the Moon. In case of the Moon is a couple of days to get back to Earth in an emergency. In case of Mars it is anywhere between six months and well over two years to get back in an emergency (last would be case where the emergency happens just as you are about to return to Earth, say your return rockets fail and you need new equipment sent from Earth, then it would be two years before your next opportunity to return to Earth).
So - I am sure by example of Apollo that NASA would not send a mission to Mars without prior missions in LEO and probably to the Moon or L1 or L2 or to Near Earth Asteroids (those are more dangerous than the Moon obviously) to test the systems thoroughly in a similar live situation first.
if you did them one after another - that's 10 or 20 years worth of missions perhaps. I think myself that is still true today, if we want to be reasonably safe. And since things would surely go wrong more like 20 than 10 years.
So that would make the 90s the first time it could be done safely supposing you start work on it in the 1970s.
Must say - this is personal opinion about how long it would take - putting it out for discussion!
Anyway - it's just as well they didn't in my view because back then, at least post Viking, nearly everyone (except Gilbert Levin) thought Mars was totally sterile, in the present, and back then they thought that probably Mars never had any life (they didn't have the evidence of Noachian period oceans on Mars we have now)
While now it seems at least possible that there are habitats there potentially, even right on the surface.
Also there is indirect isotope evidence pretty conclusive that there is some water exposed to surface conditions at least episodically in geologically recent past (can't tell if it is episodic or all the time or a bit of both).
Where To Search On Mars For Droplets, & Shallow Flows Of Liquid Water - Where Microbial Life May Flourish
That needs to be resolved - if there are habitats and where they are and if there is life in them or not - before we think about landing humans there.
Indeed also even if there is no life on Mars, still there is reason for pause for thought before introducing Earth life to it - so long as there are habitats. Because the habitats are also of great interest if they don't have life - to see what happens in such habitats without the presence of life. Are there precursors of life, or complex chemical interactions happening there? No way to test such a situation on Earth.
Will We Meet ET Microbes On Mars? Why We Should Care Deeply About Them - Like Tigers
Microbes on Mars, in the more interesting case, would be more like a microbial version of ET than a tiger
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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