In 1996, NASA researchers announced traces of fossil microorganisms embedded in a martian meteorite. Other scientists questioned their findings. And, as it stands, the issue of martian life may not be settled until people from Earth actually visit Mars. Earth and Sky asked Dr. David McKay why he's ready to make the leap of faith from life on Mars long ago to life on Mars now . . . And he explained to us that the meteorite in which the controversial traces of possible life were found was only 180 million years old.
Scientists say that earthly life has been around nearly four billion years.
If life existed on Mars as recently as hundreds of millions of years ago, then it may still survive today. McKay also pointed to rock-eating microbes, discovered recently deep inside Earth. Mars and Earth are very different on the outside, but deep underground the two planets appear similar. So McKay has predicted that explorers will someday dig up living microbes on Mars. We're Block and Byrd for Earth and Sky.