Tim Peak Event

Crashing neutron stars unlock secrets of the Universe – thanks to UK tech

On 17 August 2017 gravitational waves were detected by both LIGO and Virgo collaborations.

The ‘chirp’-like signal, called GW170817, is a great example of multimessenger astronomy, where just 1.7 seconds after the gravitational waves network saw the signal, NASA’s Fermi Gamma-ray Space Telescope and ESA’s INTErnational Gamma Ray Astrophysics Laboratory (INTEGRAL) both detected a short gamma-ray burst from the same area of the sky.

Signals like chirps and gamma-ray bursts are referred to as ‘triggers’ that start this multimessenger astronomy since they alert the astronomical community to the event, who can then focus their instruments to observe the same patch of sky.

(The advanced LIGO Livingston detector. LIGO is made up of two twin detectors, two pairs of 4km-long perpendicular pipes, one in Hanford, Washington state, the other in Livingston, Louisiana. Photo Credit: LIGO)

Over 70 different observatories, including the Hubble Telescope, were able to detect remnants of the signal in the form of fading light, the counterpart to the gravitational waves signal.  

Since operation began at LIGO and its European counterpart Virgo, based in Italy, this is the fifth time gravitational waves have been detected, where the first event was back in September 2015. This first detection of gravitational waves from a black hole merger was an achievement that was recognized with this year’s Nobel Prize in Physics.

This is the first time that researchers have detected both light and gravitational waves from the same event and provides the strongest evidence yet that short-duration gamma-ray bursts are caused by mergers of neutron-stars.

The neutron-star merger has also started to shed light on one of the big questions in physics: how heavy elements such as gold and platinum are formed. 

Find out more here, where details of the UK contribution to the discovery can be found here.