Origin of life: An artificial comet holds the missing piece
As a first step, an artificial comet was produced at the Institut d'Astrophysique Spatiale. By placing a representative mixture of water (H2O), methanol (CH3OH) and ammonia (NH3) in a high vacuum chamber at -- 200 °C, the astrophysicists simulated the formation of dust grains coated with ice, the raw material of comets. This material was irradiated with UV, as in the molecular clouds where these grains form.
|Ribose forms in the icy mantles of dust grains from simple precursor molecules|
(water, methanol and ammonia) under high-energy radiation
[Credit: © Cornelia Meinert (CNRS), Andy Christie (Slimfilms.com)]
Although the existence of ribose in real comets remains to be confirmed, this discovery completes the list of the molecular building blocks of life that can be formed in interstellar ice. It also lends further support to the theory that comets are the source of the organic molecules that made life possible on Earth, and perhaps elsewhere in the Universe.
Source: CNRS [April 08, 2016]