Scientific Simulation Backs Extraterrestrial Origins of Life
Scientists have carried out simulations that seems to support the theory according to which life’s building blocks may have formed on icy interplanetary dust and then taken to Earth, where it spawned into more complex forms.
The discovery resulted of a joint study by chemists from the University of California, Berkeley, and the University of Hawaii, Manoa.
The experiment, which simulated the cosmic environment, showed that from deep space can emerge complex depeptides – linked pairs of amino acids – that are essential building blocks shared by all living things.
These findings suggest the possibility these molecules, after forming in space, were "seeded" to Earth by a comet or possibly meteorites, catalyzing the formation of proteins (polypeptides), enzymes and even more complex molecules, such as sugars, that are necessary for life, a UC Berkeley release reported Tuesday.
"It is fascinating to consider that the most basic biochemical building blocks that led to life on Earth may well have had an extraterrestrial origin," UC Berkeley chemist Richard Mathies said.
The experiment took place in an ultra-high vacuum chamber cooled to 10 degrees above absolute zero. University of Hawaii scientists simulated an icy snowball in space including carbon dioxide, ammonia and various hydrocarbons such as methane, ethane and propane.
As it turned out, when bombarded with high-energy electrons to simulate cosmic rays in space, the chemicals reacted to form organic compounds essential to life.
An analysis at Berkeley confirmed the presence of complex molecules – nine amino acids and at least two dipeptides – capable of catalyzing biological evolution on Earth.