Small features have been found on the surface of Mars which are strikingly similar to Earth fossils of ancient worm- and mollusk-like creatures from 500 million years ago.
They may have formed as sediment filled animal burrows with fine particles. On Earth the matrix compressed inside the tunnel mineralizes into rock over millions of years. The ancient burrow casts, usually less than 5mm long, are later (hundreds of millions of years, later) sometimes exposed as the softer rock around them weathers away. They look like tiny squeezes of toothpaste.
“They look remarkably similar to Ordovician trace fossils I have studied and photographed here on Earth.”
“If not trace fossils, what other geological explanations will NASA come up with?”
https://www.leonarddavid.com/curiosity-mars-rover-investigates-eye-catching-odd-features/
Stunning to think that Mars might have had oceans swarming with life…
…even more mind-blowing that by extension billions of planets around stars in our galaxy probably still do…
Image via Concept aliens by Ken Barthelmey
but….https://www.scienceabc.com/nature/universe/why-would-finding-extinct-life-on-mars-be-the-worst-news-ever.html
Yes. But a lot of thought has gone into the Fermi Paradox, it’s not quite as straightforward or bleak as that.
For a good introduction see Isaac Arthur’s “Fermi Paradox Compendium”
I like to think apathy is the greatest filter.
has a lot of