Astronomers have found evidence for a building block of life around another star. The discovery faintly suggests that our Solar System may not be the only place life arose.
Two teams separately discovered this molecule, called methyl isocyanate. It was found by measuring the spectrum of a multiple system of very young protostars called IRAS 16293-2422, 400 light-years from Earth, using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile last year.
Specifically, the molecule was located inside the dense inner region of the disk of dust and gas that surrounds stars like these. These disks give rise to the protostars themselves, and also the components of a solar system – planets, comets, and all.
“This discovery may give us a clue that life can arise in many parts of the universe,” Rafael Martín-Doménech from the Center of Astrobiology in Spain, the co-lead on one of the teams, told IFLScience. “The Solar System may not be as special as we think.”
Methyl isocyanate is particularly exciting because it is involved in the creation of more complex molecules such as peptides and amino acids, such as proteins. This star appears to have some of the other ingredients for life too, including sugars.
Methyl isocyanate molecules contain nitrogen, carbon, and oxygen bonded together, three atoms that are common to a lot of molecules found in life organisms, like proteins. “Nitrogen, carbon, and oxygen are very important for life,” said Martín-Doménech.
This detection isn’t enough to say life could arise in this system. But it points to the start of a complex process where the building blocks of life, created by the star itself, could be stored in a young system and later transported to a planet.
While these ingredients themselves are unlikely to survive the process of planet formation, it’s possible they could be preserved in the icy mantles of comets. These would migrate to the edge of the system, where they would be kept safe until being flung inwards, possibly striking any planets now present. This idea, panspermia, is one theory for how life arose on Earth.
The next step in this line of research will be to find an amino acid in space. In particular, Martín-Doménech says astronomers are on the lookout for ricin, the simplest of amino acids. “That would be a great step for this origin of life theory,” he said, “because then you will have a building block of proteins that are present in every organism.”
As is always the case with astronomy, it will be down to bigger and more powerful telescopes to make this discovery in the future. For now, though, we’ve taken a tentative step towards the possibility that our Solar System is not that unique.
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