Deep in the cold, dark recesses of a lightyears-wide nebula known as the Taurus molecular cloud (TMC-1), astronomers have discovered cyanocoronene, the largest polycyclic aromatic hydrocarbon (PAH) ever detected in space.
PAHs have a bad reputation on Earth, as they arise from the incomplete combustion of organic matter, such as in tobacco smoke or exhaust fumes, with harmful implications to health.
In the broader Universe, however, they are thought to lock away carbon and play a key role in the chemistry that leads to the formation of stars and planets.
The study recreated cyanocoronene in the lab to determine its unique chemical signature.
With this in hand, scientists tracked observational data from TMC-1, finding clear signs of the large PAH.
Containing 24 carbon atoms, it is the largest individual PAH to have been detected in interstellar space.
Why it matters
The cyanocoronene was in similar amounts to smaller PAHs found before, hinting that such molecules may be more common in space than previously thought.
They could act as stable reservoirs of carbon, seeding new planetary systems with the ingredients for life.
Researchers now aim to find even larger PAHs and to understand how they survive the extremes of space.
"Each new detection brings us closer to understanding the origins of complex organic chemistry in the Universe – and perhaps, the origins of the building blocks of life themselves," says lead researcher Gabi Wenzel.
