25 August 2009
Scientists at NASA (the American space agency) have found an important chemical in dust collected from a comet that could help answer how life started on Earth.
The samples were collected five years ago from the 5km-wide comet called 81P/Wild-2 by their space probe Stardust but special care was taken to make sure the particles did come from the comet and not from somewhere on Earth through contamination.
The chemical glycine was found in the comet dust, which is an amino acid that is also found in proteins in living creatures here on Earth.
Some scientists believe that this chemical may have played a part in kick-starting life on Earth, when the solar system, planets and comets were forming billions of years ago.
http://news.bbc.co.uk/1/hi/sci/tech/8208307.stm