Earlier quoted context omitted.
You jest, but I seriously believe we are likely martians. Early panspermia from Mars settles a LOT of astrobiological questions about origin of life and LUCA complexity. To be clear, Mars’ descent into inhospitality was totally natural and the result of a smaller planet with stripped atmosphere just outside the habitable zone as the Sun cooled. I doubt Martian life developed to be multicellular. But I bet when we go…
But then how did life get on mars?
New findings point to an Earth-like environment on ancient Mars
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Re: New findings point to an Earth-like environment on ancient Mars
#72Kurd Lasswitz wrote "Two Planets" in 1897, https://news.ycombinator.com/item?id=39598983 > Lasswitz's Martians differ little from man physically, but ethically, intellectually, scientifically, and socially they are the prototype of the ideal human being. They seek to educate man, asking in return only air and energy to supplement the diminished supplies in their own, older world. The story revolves around a group of…
Von Braun is a highly controversial figure widely seen as escaping justice for his Nazi war crimes due to the Americans' desire to beat the Soviets in the Cold War
Re: New findings point to an Earth-like environment on ancient Mars
#73Earlier quoted context omitted.
Your numbers give Mars an extra ~800 million years. Nothing even close to 3/4 billion. Besides, deciding what was inhospitable for early life is an exercise of noisy assumptions. I'd bet the error margin is larger than that difference.
3/4 billion = 750 million, no?
Re: New findings point to an Earth-like environment on ancient Mars
#74It really was Earth all along...
Re: New findings point to an Earth-like environment on ancient Mars
#75Earlier quoted context omitted.
Mars had 3/4 billion more years to develop, compared with the Earth. Mars formed first, and cooled first due to its smaller size. One of the outstanding problems in astrobiology I mention is that the Earth was inhospitable until 3.8Gya, and the oldest fossils of presumably DNA based life (since it matches existing life we can study) was 3.7Gya. Mars was hospitable ~4.5Gya. So either life emerged IMMEDIATELY on Earth…
At this point, given how much Mars had been roved, why hasn’t some fossil record been discovered yet? At the very least, I would expect something akin to chalk left behind by proto-diatoms that had calcium carbonate skeletons.
Re: New findings point to an Earth-like environment on ancient Mars
#76Earlier quoted context omitted.
How does earth get seeded?
If there were extra-terrestrial intervention, it would only have needed to be a one-time event. And it wouldn't be technologically hard to do it such that no trace remains over those timescales. So, yes, that's "crazy". On the other hand, it's unfalsifiable in the absence of other theories.
Re: New findings point to an Earth-like environment on ancient Mars
#77Earlier quoted context omitted.
But then how did life get on mars?
Mars had 3/4 billion more years to develop, compared with the Earth. Mars formed first, and cooled first due to its smaller size. One of the outstanding problems in astrobiology I mention is that the Earth was inhospitable until 3.8Gya, and the oldest fossils of presumably DNA based life (since it matches existing life we can study) was 3.7Gya. Mars was hospitable ~4.5Gya. So either life emerged IMMEDIATELY on Earth…
Re: New findings point to an Earth-like environment on ancient Mars
#78Earlier quoted context omitted.
Your numbers give Mars an extra ~800 million years. Nothing even close to 3/4 billion. Besides, deciding what was inhospitable for early life is an exercise of noisy assumptions. I'd bet the error margin is larger than that difference.
????????? 800 million is greater than 3/4 billion?
Re: New findings point to an Earth-like environment on ancient Mars
#79Earlier quoted context omitted.
Mars had 3/4 billion more years to develop, compared with the Earth. Mars formed first, and cooled first due to its smaller size. One of the outstanding problems in astrobiology I mention is that the Earth was inhospitable until 3.8Gya, and the oldest fossils of presumably DNA based life (since it matches existing life we can study) was 3.7Gya. Mars was hospitable ~4.5Gya. So either life emerged IMMEDIATELY on Earth…
Your numbers give Mars an extra ~800 million years. Nothing even close to 3/4 billion. Besides, deciding what was inhospitable for early life is an exercise of noisy assumptions. I'd bet the error margin is larger than that difference.
Re: New findings point to an Earth-like environment on ancient Mars
#80Earlier quoted context omitted.
Mars had 3/4 billion more years to develop, compared with the Earth. Mars formed first, and cooled first due to its smaller size. One of the outstanding problems in astrobiology I mention is that the Earth was inhospitable until 3.8Gya, and the oldest fossils of presumably DNA based life (since it matches existing life we can study) was 3.7Gya. Mars was hospitable ~4.5Gya. So either life emerged IMMEDIATELY on Earth…
That still doesn't answer the question. How did life start on Mars?