The surprise discovery of a huge cloud of molecular gas — the stuff that forms stars — just 300 light-years away is opening up new ways to study the conditions that enable star birth.

Stars form from collapsing clouds of molecular gas. We see this in the likes of the Orion Nebula, which gets energized by hot ultraviolet radiation of the young stars born within. However, finding molecular clouds before they begin producing stars is more difficult.

Such clouds are predominantly made from molecular hydrogen gas, which, when it isn’t being energized by starlight, is very faint — almost invisible. (Atomic hydrogen, on the other hand, is easily detectable by radio telescopes). Astronomers usually use radio telescopes to detect carbon monoxide, which is available in much lower quantities in molecular clouds, as a proxy.