Gravitational wave insight is discovery boon

Researchers have discovered that gravity travels at the same speed of light, after detecting gravitational waves and light from two neutron stars colliding. The scientists also discovered that heavy elements such as gold, platinum and uranium are created through these collisions. This collision, 130 million years ago, created as much gold as the mass of the Earth. Another effect of the collision was the creation of short gamma-ray bursts.

Dr Joe Lyman, from the University of Warwick, said: “The exquisite observations obtained in a few days showed we were observing a kilonova, an object whose light is powered by extreme nuclear reactions. This tells us that the heavy elements, like the gold or platinum in jewellery are the cinders, forged in the billion degree remnants of a merging neutron star.”

The neutron stars were very dense, the mass of our Sun, with a diameter of 10km. Growing closer over millions of light years, they began to revolve around each other, eventually at a speed of five hundred times per second. The gravitational waves caused by the collision were detected in mid-August, with a short duration gamma-ray burst detected by the Fermi satellite two seconds later.

Professors Andrew Levan, also from Warwick University and Nial Tanvir – from the University of Leicester – were able to pinpoint the source using infrared light at the European Southern Observatory.

Professor Levan, said: “Once we saw the data, we realised we had caught a new kind of astrophysical object. This ushers in the era of multi-messenger astronomy, it is like being able to see and hear for the first time.”

Dr Samantha Oates, also from Warwick University, said: “This discovery has answered three questions that astronomers have been puzzling for decades: what happens when neutron stars merge? What causes the short duration gamma-ray bursts? Where are the heavy elements, like gold, made? In the space of about a week all three of these mysteries were solved.”