Astro-amino acids suggest life fell from the stars
11 Apr 2008 by Evoluted New Media
The theory of panspermia - that life on planets like Earth and Mars was seeded from space - has received a boost as scientists claim to have found amino acids in their highest ever concentration in two ancient meteorites which crashed to Earth millions of years ago.
The theory of panspermia - that life on planets like Earth and Mars was seeded from space - has received a boost as scientists claim to have found amino acids in their highest ever concentration in two ancient meteorites which crashed to Earth millions of years ago.
The research team believes that the presence of amino acids in these meteorites provides clear evidence that the early solar system was richer in life’s raw materials than previously thought and that these materials may have helped to kick-start life on this planet.
Lead researcher, Dr Zita Martins, from Imperial College London’s Department of Earth Science and Engineering, explains: “We know that approximately 3.8 to 4.5 billion years ago the Earth underwent heavy bombardment from meteorites which brought molecules to our planet, just before life emerged on Earth. However, there is a gap in knowledge about how life came into being. Our work has shown that it may have been meteoritic amino acids and other biologically useful compounds that spurred life into existence.”
The team found amino acids in two ancient meteorites called CR chondrites, which were found in Antarctica in the 1990s. By analysing the isotopic carbon content of these meteoritic amino acids, they determined that, unlike Earth based amino acids which prefer a lighter variety of carbon, their samples were made from a heavier carbon which could only have been formed in space.
Amino acids form the basis of proteins and enzymes, which are the building blocks of all biological life. They have been found in ancient carbon rich meteorites, which are fragments of asteroids formed shortly after the birth of the solar system.
The research team believes that the presence of amino acids in these meteorites provides clear evidence that the early solar system was richer in life’s raw materials than previously thought and that these materials may have helped to kick-start life on this planet.
“Our increasing understanding of the materials available for the first living systems in the solar system suggests that we are all products of cosmic chemistry,” said Dr Martins.
