Comet impacts may have triggered life on earth, new experiment shows
The impacts of comets might have led to the creation of life on earth, scientists claim after a recent laboratory experiment. They came to this conclusion after mimicking the conditions of comet impacts on Earth at the time when life first appeared, which was around four billion years ago.
The experiment was carried out by Dr Haruna Sughara from the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) in Yokahama and Dr Koichi Mimura from Nogoya. It adds to previous studies that claim organic molecules on comets helped create life on our planet.
Taking frozen mixtures of amino acid, water ice and silicate at 196 degree Celsius, the researchers used a propellant gun to simulate the shock of a comet impact. They studied the post-impact mixture with gas cartography and found that some of the amino acids had joined into short peptides of up to three units long.
Now peptides or simple protein chains are believed to have arisen from the stew of amino acids – the building blocks of proteins – to create life. Taking into account the experimental data, the researchers were able to estimate that the amount of peptides produced would be around the same as had been believed to be produced by normal Earth processes, like lighting, storms or hydration and dehydration cycles.
"Our experiment showed that the cold conditions of comets at the time of the impacts were key to this synthesis, as the type of peptide formed this way are more likely to evolve to longer peptides," said Dr Sugahara as reported by the Daily Mail.
This means that comet impacts may have played an important role in bringing the seeds of life to the early Earth. The finding also points that similar chemical evolution might have occurred in other alien planets due to cometary-derived peptides.
In fact, even within our own solar system the icy satellites of Jupiter and Saturn, such as Europa and Enceladus may have undergone a similar comet bombardment, scientists claim, reports the Daily Mail.
