Quote - Well, in a roundabout way, we could all be Martians. Bits and pieces of Mars have been pelting us for eons. 

Looking at it in a similar way, we're all alien - even the aliens are aliens. ;-)

Nothing existed in the entire Universe except for hydrogen and helium prior to the first star lighting up in nuclear fusion, and no elements heavier than helium, beryllium and boron can be created except in a star, and nothing heavier than oxygen can be created without a supernova explosion of a star.

As the late great Carl Sagan used to love to say, we are all made of star stuff. ;-)

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