Cosmic “dust factory” reveals clues to how stars are born

Artist's impression of a supernova. Red shows the dust. Credit: A. Angelich; NRAO/AUI/NSF

A group of scientists led by researchers at Cardiff University say they have discovered a rich inventory of molecules at the centre of an exploded star for the very first time.

Two previously undetected molecules were found in the cooling aftermath of Supernova 1987A, located 163,000 light years away in a nearby neighbour of our own Milky Way galaxy. The explosion was originally witnessed in February 1987, hence its name.

It was previously thought that the massive explosions of supernovae would completely destroy any molecules and dust that may have been already present.

But scientists say finding these unexpected molecules suggests the explosive death of stars could lead to clouds of molecules and dust at extremely cold temperatures, which are similar conditions to those seen in a stellar nursery where stars are born.

Our results have shown that as the leftover gas from a supernova begins to cool down to below ‑200°C, the many heavy elements that are synthesised can begin to harbour rich molecules, creating a dust factory.

Dr Mikako Matsuura, from Cardiff University’s School of Physics and Astronomy

The team arrived at their findings using the Atacama Large Millimeter/submillimeter Array (ALMA) to probe the heart of Supernova 1987A in remarkably fine detail.

The findings have been published in the journal Monthly Notices of the Royal Astronomical Society.