Methanol could survive the birth of a solar system

Methanol is known to be a bridge between simple molecules in space and more complex ones. New observations suggest it survives the harsh conditions that form solar systems, which means chemical complexity may be more widespread in the universe than scientists thought (Nat. Astron. 2021, DOI: 10.1038/s41550-021-01352-w).

In space, methanol predominantly forms from carbon monoxide ice, and is a precursor to esters, ketones, aldehydes, and other types of molecules. But Alice Booth, a postdoctoral research at Leiden University, says she and her group couldn’t explain its presence around a young star about 315 light years away named HD 100546. The disk of gas and dust surrounding the star—the material that can eventually condense into planets—is too hot for CO ice, and other chemical pathways can’t account for the abundance they observed.

Instead, they suggest methanol can survive the heat and radiation that is generated as a protoplanetary disk forms from cold interstellar dust and gas. Astrochemist Karin Öberg of Harvard University says evidence from our own solar system has made scientists suspect organic molecules from interstellar space might make their way into comets, asteroids and planets, “but this is the first clear evidence of this process for an extra-solar system.” Öberg wasn’t part of this project but has current and past collaborations with some of the researchers.

The finding suggests that complex molecules are widespread in the universe, which could mean the ingredients for life are everywhere. “This work implies that stars of all shapes and sizes retain chemically rich material from their birth environment, and therefore if planets can form, they’ll have ‘the right stuff’ for life at the ready,” says Ilse Cleeves of the University of Virginia, who studies protoplanetary disks and was not a member of the research group.

The researchers used the Atacama Large Millimeter/submillimeter Array to make these observations. Booth says the group hopes to make similar observations of other disks and look for molecules like ether, acetaldehyde, and methyl formate.