Actually back in the late C19 and early C20 they thought that even the Moon was habitable. Up to about 2018 or so Mars was thought to be habitable. But they soon discovered that there was not enough oxygen to breath.
So - supposing they were - well if they'd had oxygen, they'd have had life. Hard to see any way that humans could breath on either planet without life.
So - I think if there was life on Mars or Venus - most likely yes there would be an all out push to go there - back then. Or for the Moon - they'd have gone there right away.
And - we could do it. Had ideas for rotating space stations. We'd have developed artificial gravity and tether spin. Developed much better closed system habitats than anything we have now. Would have taken a while though. Because you would have had to test for long duration missions close to Earth first.
That was the key to Apollo - to test everything close to Earth first. So, surely they would have done multi-year long missions close to Earth. With so much incentive to go there - and back then automated rovers not anything like as capable as they are now, the only way to find out would be to get there.
Perhaps by the 1980s, starting from the 1960 with an all out, multi-national push - we'd have humans on Mars or Venus.
But - I think that would have been a disaster in that situation. Who knows - maybe this is one of the things that makes ET species extinct in our galaxy.
That is unless magically - it had oxygen but no life. Hard to see how that is possible.
So must be life there. And in that case - that life could be hazardous for humans. Apart from anything else, it could be XNA based life, life that has a different basis from Earth life. And would be returned to Earth.
They would have had a go at quarantining the crew and samples on return, I'm sure. But the capabilities they had back then were woefully inadequate for containing any micro-organisms which we now know could be too small to be seen in a microscope (they didn't know that then). That's just Earth life, never mind life with a different non DNA basis.
For instance, suppose that XNA based life is a bit better at photosynthesis than the green algae on Earth - but is inedible to Earth life. Perhaps also it creates an organic compound that is similar to a compound used in our biology - but not identical, making it poisonous to Earth life.
Or - it is just overall better at metabolizing than Earth life and sets up a self contained ecosystem - microbial film or whatever.
Nowadays - in the reports on returning samples from Mars then scientists say we have to take great care not to contaminate Earth with Mars life - if it exists - until we know what is there.
There might be nothing in case of Mars And at most microbial and hardly likely to be a great diversity of species, still there is enough need for caution to suggest elaborate precautions which we simply wouldn't have known were necessary in the 1970s.
But in case of another planet like Earth with its own life, then - there would be such diversity of species surely, that extreme caution would be needed until we knew it better.
I think that humans as we were back in the 1970s, with a few exceptions like Carl Sagan, would not have given that much thought. And the few that did would not be aware of the precautions we now know are necessary.
So - is possible we had a lucky escape there actually.
It might also have made it harder to sign the Outer Space Treaty and to have peaceful exploration of space.
So - supposing they were - well if they'd had oxygen, they'd have had life. Hard to see any way that humans could breath on either planet without life.
So - I think if there was life on Mars or Venus - most likely yes there would be an all out push to go there - back then. Or for the Moon - they'd have gone there right away.
And - we could do it. Had ideas for rotating space stations. We'd have developed artificial gravity and tether spin. Developed much better closed system habitats than anything we have now. Would have taken a while though. Because you would have had to test for long duration missions close to Earth first.
That was the key to Apollo - to test everything close to Earth first. So, surely they would have done multi-year long missions close to Earth. With so much incentive to go there - and back then automated rovers not anything like as capable as they are now, the only way to find out would be to get there.
Perhaps by the 1980s, starting from the 1960 with an all out, multi-national push - we'd have humans on Mars or Venus.
But - I think that would have been a disaster in that situation. Who knows - maybe this is one of the things that makes ET species extinct in our galaxy.
That is unless magically - it had oxygen but no life. Hard to see how that is possible.
So must be life there. And in that case - that life could be hazardous for humans. Apart from anything else, it could be XNA based life, life that has a different basis from Earth life. And would be returned to Earth.
They would have had a go at quarantining the crew and samples on return, I'm sure. But the capabilities they had back then were woefully inadequate for containing any micro-organisms which we now know could be too small to be seen in a microscope (they didn't know that then). That's just Earth life, never mind life with a different non DNA basis.
For instance, suppose that XNA based life is a bit better at photosynthesis than the green algae on Earth - but is inedible to Earth life. Perhaps also it creates an organic compound that is similar to a compound used in our biology - but not identical, making it poisonous to Earth life.
Or - it is just overall better at metabolizing than Earth life and sets up a self contained ecosystem - microbial film or whatever.
Nowadays - in the reports on returning samples from Mars then scientists say we have to take great care not to contaminate Earth with Mars life - if it exists - until we know what is there.
There might be nothing in case of Mars And at most microbial and hardly likely to be a great diversity of species, still there is enough need for caution to suggest elaborate precautions which we simply wouldn't have known were necessary in the 1970s.
But in case of another planet like Earth with its own life, then - there would be such diversity of species surely, that extreme caution would be needed until we knew it better.
I think that humans as we were back in the 1970s, with a few exceptions like Carl Sagan, would not have given that much thought. And the few that did would not be aware of the precautions we now know are necessary.
So - is possible we had a lucky escape there actually.
It might also have made it harder to sign the Outer Space Treaty and to have peaceful exploration of space.
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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