We may all be space aliens: study

Have you ever looked at humans and thought about how strange and alien we look? You may correct.

European and US scientists have proved for the first time that two bits of genetic coding, called nucleobases, contained in the meteor fragment, are truly extraterrestrial. Genetic material from outer space found in a meteorite in Australia may well have played a key role in the origin of life on Earth, according to a study to be published Sunday.Previous studies had suggested that the space rocks, which hit Earth some 40 years ago, might have been contaminated upon impact. Both of the molecules identified, uracil and xanthine, "are present in our DNA and RNA," said lead author Zita Martins, a researcher at Imperial College London. ... A team of European and US scientists showed that the two types of molecules in the Australian meteorite contained a heavy form of carbon -- carbon 13 -- which could only have been formed in space. "We believe early life may have adopted nucleobases from meteoric fragments for use in genetic coding, enabling them to pass on their successful features to subsequent generations," Martins said. If so, this would have been the start of an evolutionary process leading over billions of years to all the flora and fauna -- including human beings -- in existence today. ... Uracil is an organic compound found in RNA, where it binds in a genetic base pair with another molecule, adenine. Xanthine is not directly part of RNA or DNA, but participates in a series of chemical reactions inside the RNA of cells. - bbart

The image of a DNA shaped nebula was captured by NASA's Spitzer Space Telescope.