August 6 - Life on Mars?????!?!!!

Posted on August 6, 2020

Meteorites are found all the time - especially in Antarctica, where the dark space stones show up well on the ice!



Scientists think that some meteorites found on the Earth originated on Mars. These meteorites are made up of elements in the same mix as rocks and air on Mars. 


You may wonder, okay, but how do rocks on Mars travel to Earth?

Most meteorites are created when something in space impacts another something - for example, when two asteroids collide, or when an asteroid hits a moon or planet - and those impacts spray rocks in all directions - some towards Earth's orbit. So it makes sense that some meteorites found on Earth are from Mars!

Okay, so we find meteorites often, and meteorites that originated on Mars sometimes...

But what about a meteorite - found on Earth - that has evidence of ancient life on Mars?

On this date in 1996, a group of scientists announced that they had found evidence for ancient microscopic life inside a Mars-originating meteorite!

Wow! That would be an absolute first - first evidence of actual life on another planet or another anything-other-than Earth.

BUT, alas, the electron microscopic photos that seemed to show fossilized bacteria could be explained in less dramatic ways. For example, the wormlike structures could just be uneven patches in the coating used to study samples with electron microscopes!


It's not certain that the meteorite (ALH 84001) does NOT have microfossils, but it's also not certain that it does. Science inches forward by testing and retesting hypotheses - which are educated guesses of how things work - and by replicating earlier work. Some scientists who work with meteorites, with Martian rocks still on Mars, and with astrobiology are trying to look for evidence of ancient Martian life, trust me! 

So even though science-in-general finds the claim about ALH 84001 premature, it's not ridiculous and might - unlikely, but might - prove to be true.


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