Did life once thrive on the moon four billion years ago?

[C C]

http://blogs.discovermagazine.com/d-brie...-long-ago/

EXCERPT: The Moon is completely inhospitable and barren with no semblance of life on its surface, however, this may not have always been the case. Scientists have discovered that at two points in the natural satellite's four billion year existence, the Moon could have harboured life. [...] One window for life to flourish was shortly after its formation 4 billion years ago. The second was 3.5 billion years ago and was caused by lunar volcanic activity. Scientists believe the moon was spewing out large quantities of volatile gases. Life on Earth may have started in a similar manner, however, the more likely explanation is that living bacteria crash landed here on a meteorite...

MORE: http://www.dailymail.co.uk/sciencetech/a...s-ago.html

[Zinjanthropos]

Makes me wonder if the moon rocks have yielded microfossils. Also, while the moon was getting whacked by other sizeable bodies wasn't the Earth also getting bombarded and if so wouldn't there be a chance of pieces of Earth impacting the moon?

[C C]

Makes me wonder if the moon rocks have yielded microfossils.

Oldest microbes discovered on Earth date to circa 3.5 billion years ago, but large accretionary structures caused by cyanobacteria go back to two or three hundred million years before that. There's indirect hints ("chemo-fossil" signs) of life at 4.1 billion years. The latter vagueness is probably the best the Moon could remotely provide, since any pools of water on the satellite were probably too brief, unstable or intermittent for mounds resembling stromatolites to form.

Also, while the moon was getting whacked by other sizeable bodies wasn't the Earth also getting bombarded and if so wouldn't there be a chance of pieces of Earth impacting the moon?

Or Mars, which some geochemists and astrobiologists literally advocate as the source itself of life on Earth. The formation of RNA in water is supposedly difficult without the presence of boron, which there was little of on primeval Earth. But there's a line of thought that there was plenty of boron on Mars.

"Mars had a stable crust 4.5 billion years ago, at a time when Earth was still in the throes of recovery from the moon-forming impact," said Jay Melosh of the Lunar and Planetary Lab at the University of Arizona. "So conditions on Mars were conducive to the origin of life long before those on Earth." Melosh explains what might have happened next: "Once life began on Mars, the Late Heavy Bombardment [lots of big rocks crashed into Earth and Mars about 4 billion years ago] would have provided abundant means of transport for the Mars-Earth diaspora. --Eight-Legged Space Survivor Gives 'Panspermia' New Life

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[Yazata]

http://blogs.discovermagazine.com/d-brie...-long-ago/

EXCERPT: The Moon is completely inhospitable and barren with no semblance of life on its surface, however, this may not have always been the case. Scientists have discovered that at two points in the natural satellite's four billion year existence, the Moon could have harboured life. [...] One window for life to flourish was shortly after its formation 4 billion years ago. The second was 3.5 billion years ago and was caused by lunar volcanic activity.

It's an interesting question.

I flat out don't believe that life just pops into existence quickly. Even the simplest known life on Earth today is already incredibly complex on the molecular biology level. So if we assume that the first life was something like the bacteria or archaea of today, I have to imagine a whole exceedingly complex chemical process leading up to its appearance.

Of course, today's bacteria and archaea might be the products of billions of years of evolution themselves and nothing like unchanged biological survivors from the earliest days of life. So conceivably the very first cells were much simpler than today's bacteria and totally unlike them. As the more evolved cells including adaptations upon adaptations appeared, they may have competed the older kind of cells to extinction.

But having said that, I'd wonder whether a couple of brief periods in the Moon's history would be long enough for even the simplest proto-life to form. My gut (my infallible guide) says 'no'.

Scientists believe the moon was spewing out large quantities of volatile gases.

Would they have been biologically useful gases? Would liquid water have existed on the Moon?

Makes me wonder if the moon rocks have yielded microfossils. Also, while the moon was getting whacked by other sizeable bodies wasn't the Earth also getting bombarded and if so wouldn't there be a chance of pieces of Earth impacting the moon?

I like that idea. Mini-panspermia. If life really did appear very early in the Earth's history, back in the Late Heavy Bombardment when the Earth was getting struck regularly by asteroid impacts (the impacts that pocked the Moon with its craters), it's possible to imagine bits of planet Earth with this earliest life aboard being ejected and making it to the Moon where the living passengers might have been able to survive and reproduce.

And if more grand-scale panspermia is true, and life on Earth originally arrived from somewhere else (an exoplanet around another star?), then the Moon might have been seeded from that source too.

So as unlikely as it initially sounds, it might be interesting to look for microfossils on the Moon.

[Zinjanthropos]

So as unlikely as it initially sounds, it might be interesting to look for microfossils on the Moon.

That's what I was wondering, do the Apollo moon rocks contain microfossils? I couldn't find anything that says they do but could be many a scientist not wishing to stake their reputation on it. Maybe this little article is meant to prepare us for an official announcement and take the pressure off. 

One question I do have is whether fossils could form on the moon? If not possible and there are microfossils present then I might deduce that they came from somewhere else.

[RainbowUnicorn]

given that the moon was supposedly an plant that struck earth and had a mix of elements and comets strike it.
it would be reasonable to expect it probably had water on it for some millions of years.
thus it is likely to have had bacterial life on it.

what makes it more difficult to find evidence of that is because it has been dry roasted by radiation for several million years.
that tends to cook off things a little

---

So as unlikely as it initially sounds, it might be interesting to look for microfossils on the Moon.

That's what I was wondering, do the Apollo moon rocks contain microfossils? I couldn't find anything that says they do but could be many a scientist not wishing to stake their reputation on it. Maybe this little article is meant to prepare us for an official announcement and take the pressure off. 

One question I do have is whether fossils could form on the moon? If not possible and there are microfossils present then I might deduce that they came from somewhere else.

critical process of Fossilization is the adding of another layer on top.
the moon would not get that other layer on top

[Zinjanthropos]

Thought this was kind of cool. 8 years old but worth a listen to.

https://www.ted.com/talks/mark_roth_susp...on/up-next

After listening to it I thought maybe we might be setting our sights too low. Life might actually be waiting for us up there, just have to warm it up

Wondering if subterranean goldilocks zones could exist on many star orbiting planets/moons? Even if the zones were at times severely cold. And is there a better refrigerator/freezer than outer space?