Violent collision between two neutron stars captured by JWST

Precious elements including gold, platinum and uranium are thought to be formed in space during neutron star collisions – and the James Webb Space Telescope (JWST) has just found evidence of one in action.

A team of astronomers discovered the violent crash, known as a ‘kilonova’, by using the JWST to trace a dazzling gamma-ray burst (GRB) back to its source beyond our galaxy. 

The GRB, designated 230307A, is the second-brightest ever seen. It was first detected on March 7 by Nasa’s Fermi Gamma-ray Space Telescope, and lasted around 34 seconds. 

Following the GRB to its source, the team twice observed the kilonova, and detected emissions from a process known as neutron capture, or the r-process.

The r-process, which only occurs in extremely violent conditions, enables atomic nuclei to capture extra neutrons, creating new, heavier elements such as gold.

While the JWST didn’t catch a glint of gold, it did show evidence of tellurium, a brittle, mildly toxic element used in CDs and DVDs, and lanthanides, a group of 15 rare-earth elements heavier than lead.

Writing on Twitter, co-author Brian Metzger said: ‘In work led by Andrew Levan we detected kilonova emission (for the first time!) with JWST, after a GRB.

‘In perhaps the biggest plot twist: the GRB – the second brightness of all time – lasted half a minute, i.e. a second “long” burst accompanied by r-process production. Likely a neutron star merger, but one which challenges our ideas about how long the central engine should “jet”.’

The paper has not yet been peer-reviewed.