Where did human life come from? That's the ultimate question. Science offers two solutions to this question. One is that life was placed here either by an intelligent being, or by chance via a meteorite back when the Earth was very young. The second option is that space is filled with the building blocks of life, and the gas and dust that the Earth formed from happened to contain these materials. Until now there was really no strong proof either way, but just recently astronomers made a huge discovery. Astrobiologists were studying the composition of a meteorite they found in the arctic and discovered guanine and adenine, two of the four building blocks of DNA! These proteins have never been found in outer space before, and astronomers believed conditions to be too harsh for these proteins to survive. Finding guanine and adenine in this meteorite suggests that these and other building block of DNA are created during supernova explosions and exists all throughout outer space. It's likely that these materials existed in the circumstellar disk around the sun back when it was very young, and therefore ended up here on Earth. This also promotes the idea that other intelligent life may be out there since the building blocks for life seem to be free floating through space. There are of course religious based views on the formation of life, which I respect very much, but from a purely scientific standpoint, it appears that we really are a product of the stars.
Image Credit: NASA
Go to NASA.gov to read the article pertaining to this discovery.
