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New findings point to an Earth-like environment on ancient Mars

discover.lanl.gov

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Re: New findings point to an Earth-like environment on ancient Mars

#61

Post by marcosdumay »

adastra22 wrote: post #37
NegativeLatency wrote: post #28

Earlier 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…

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

#62

Post by 48864w6ui »

adastra22 wrote: post #41
bena wrote: post #33

Earlier quoted context omitted.

Exactly, panspermia isn't an answer, it's kicking the can down the road. The only thing panspermia can tell us is that it's ok if we can't find evidence for the genesis of life on Earth.

Which is an important advance because genesis of life on Earth is getting harder and harder to answer as we gather more evidence. Pushing it to another environment (and longer time frame) does in fact solve a number of problems.

What evidence? Do we no longer figure ~4by bp?

Re: New findings point to an Earth-like environment on ancient Mars

#63

Post by xattt »

adastra22 wrote: post #37
NegativeLatency wrote: post #28

Earlier 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…

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

#64

Post by ethbr1 »

jerpint wrote: post #47
adastra22 wrote: post #37

Earlier 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…

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

#65

Post by walterbell »

Kurd 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 German scientists who, when seeking the North Pole, come upon a Martian settlement there..

A young German reader of "Two Planets", Wernher von Braun, would develop ballistic missiles for Germany/USA, rockets that launched the first US space satellite and the NASA launch vehicle that took Apollo to the Moon.

https://en.wikipedia.org/wiki/The_Martians_(scientists)

> Leo Szilard, who jokingly suggested that Hungary was a front for aliens from Mars, used this term. In an answer to the question of why there is no evidence of intelligent life beyond Earth (called the Fermi paradox) despite the high probability of it existing, Szilárd responded: "They are already here among us – they just call themselves Hungarians."

The group included Erdos and von Neumann.

Re: New findings point to an Earth-like environment on ancient Mars

#66

Post by Shatnerz »

marcosdumay wrote: post #61
adastra22 wrote: post #37

Earlier 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.

3/4 billion = 750 million, no?

Re: New findings point to an Earth-like environment on ancient Mars

#67

Post by 48864w6ui »

baja_blast wrote: post #38
FrustratedMonky wrote: post #8

Earlier quoted context omitted.

Or, why aren't Martians from Earth. As much as I like the idea conceptually for movies. That life on Earth came from Mars still doesn't explain how life started on Mars. It just moves the location, the mechanism is still tbd.

Yeah I never liked the panspermia as a solution to how life started so quickly on Earth because it just kicks the can down the road. But hey it has been speculated that DNA may be almost 10 billion years old https://phys.org/news/2013-04-law-life-began-earth.html . But this is just a thought experiment, I am unsure if we know how long it takes for DNA to double, nor do we know if the rate would be constant over time.…

Recall that no one could reconcile billion year ages for the earth with it not having cooled far more - until the discovery of radioactivity.

Re: New findings point to an Earth-like environment on ancient Mars

#68

Post by Teever »

marcosdumay wrote: post #61
adastra22 wrote: post #37

Earlier 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.

?????????

800 million is greater than 3/4 billion?

Re: New findings point to an Earth-like environment on ancient Mars

#69

Post by jl6 »

adastra22 wrote: post #37
NegativeLatency wrote: post #28

Earlier 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…

> Earth was inhospitable until 3.8Gya

There is much uncertainty about this. The early Earth was a volatile place with a lot of raw materials and energy available, and a lot of chemistry happening. I wouldn't rule out that some part of Earth may have had the right conditions for life right from the beginning. Certainly if we expect life to be able to survive a ride on a piece of ejecta from Mars, it's plausible to imagine it surviving in some boundary niche amidst the heat and fury of the Hadean Earth.

Re: New findings point to an Earth-like environment on ancient Mars

#70

Post by [deleted] »

marcosdumay wrote: post #61
adastra22 wrote: post #37

Earlier 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.

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