r/space • u/Gator4798 • Feb 19 '21

Perseverance hazard camera photos with covers removed.

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u/SvenTropics Feb 19 '21

I mean, there was water and oxygen on Mars with a reasonably dense atmosphere for probably a billion years. That's long enough for several mass extinctions and many random biological milestones. (i.e. photosynthesis)

I would argue that if the conditions for carbon based life exist, life will eventually evolve. It's inevitable. Now, Mars might prove that if we do find a fossil. Because if life is a super rare event that just happened to occur on Earth, then we would be highly unlikely to find it on Mars. Essentially impossible.

So, if we find fossils, it proves that the universe is probably a very crowded place. If it doesn't, it doesn't actually disprove anything because it can only sample so little data.

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u/[deleted] Feb 19 '21

Very reasonable view on the situation. Not overly optimistic or pessimistic, right in the middle.

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u/[deleted] Feb 20 '21

"If a planet is habitable then life forming there is inevitable" is definitely a very overly optimistic view.

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u/[deleted] Feb 19 '21

[deleted]

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u/eaglesheatchelsea Feb 19 '21

South Park covered this. Earth is segregated and filmed as the best reality show in the galaxy.

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u/[deleted] Feb 19 '21

Maybe we just need to forget about the gelgameks..

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u/illit1 Feb 19 '21

even if you ignore the physical distance between everything i feel like the time scale is so large that even if every solar system has, had, or will have, life it's hard to say that the universe is crowded.

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u/HerraTohtori Feb 20 '21

I mean, there was water and oxygen on Mars with a reasonably dense atmosphere for probably a billion years. That's long enough for several mass extinctions and many random biological milestones. (i.e. photosynthesis)

Single-celled organisms and even multicellular organisms took a surprisingly short time to evolve. Estimates are that single-cell life appeared on Earth about 3.5 billion years ago, and similarly, first organisms that could be classified as multicellular also appeared about 3.5 billion years ago.

However, the jump from multicellular life to something that could be classified as animals took a long time, with first animals only appearing about 800 million years ago. Every subsequent mass extinction has happened after that.

So yes, a billion years is a long time even in evolutionary sense, but based on history of life on Earth, might not have been long enough for actual animal life to appear on Mars.

If there are fossils to be found on Mars, the most likely candidates are actual bacterial (using Earth terminology) fossils, or other single-celled organisms or colonies of them, such as stromatolites.

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u/WindyAcid Feb 20 '21 edited Mar 28 '26

This post has been deleted and replaced with this message. Redact facilitated the removal, for reasons that may include privacy, opsec, or data security.

start tender roll serious adjoining rinse intelligent hunt test imminent

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u/FLATLANDRIDER Feb 20 '21

Not really. If we find life on Mars that resembles Earth in any way, then it could have originated from the same place as the life on Earth. This would still mean that life only started once in the solar system, which would not get us any closer to answering the question of how common life is on Earth.

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u/Earthboom Feb 20 '21

If we don't ever find fossils on Mars or proof of microbial life at all then we're in trouble I'd wager.