A team of international scientists led by the University of East Anglia (UEA) have discovered two neutron stars locked in a tight orbit, which they believe will unlock some of the universe's biggest mysteries.
They've discovered an unusual pulsar (known as PSR J1913+1102) - or neutron-star - which is part of a binary system and therefore locks in a tight orbit with another neutron star.
The stars are dead stellar remnants of a supernova and it's believed they'll collide and merge in around 470 million years, which will then release large amounts of energy in the form of gravitational waves and light.
But where scientists have found the discovery unusual is that one of the stars is far larger than the other and scientists are confident this will help them to understand more about the expansion rate of the universe - known as the Hubble constant.
The discovery - which was published yesterday (08/07/20) - was made using a telescope in Puerto Rico.
Lead researcher Dr Robert Ferdman, from UEA’s School of Physics, said:
“Back in 2017, scientists at the Laser Interferometer Gravitational-Wave Observatory (LIGO) first detected the merger of two neutron stars.
“The event caused gravitational-wave ripples through the fabric of space time, as predicted by Albert Einstein over a century ago.”
This was seen through traditional telescopes at observatories around the world, which identified the event known as GW170817 in a distant galaxy, 130 millions light years from our own Milky Way.
Dr Ferdman said:
“It confirmed that the phenomenon of short gamma-ray bursts was due to the merger of two neutron stars.
"And these are now thought to be the factories that produce most of the heaviest elements in the Universe, such as gold.”
The merging of two neutron stars is estimated to release ten times the amount of power in just a fraction of a second, than all stars in the Universe combined, so this event did not surprise scientists, but the brightness ejected was a mystery.
Dr Ferdman said:
“Most theories about this event assumed that neutron stars locked in binary systems are very similar in mass.
“Our new discovery changes these assumptions.
"We have uncovered a binary system containing two neutron stars with very different masses.
“These stars will collide and merge in around 470 million years, which seems like a long time, but it is only a small fraction of the age of the Universe.
“Because one neutron star is significantly larger, its gravitational influence will distort the shape of its companion star – stripping away large amounts of matter just before they actually merge, and potentially disrupting it altogether.
“This ‘tidal disruption’ ejects a larger amount of hot material than expected for equal-mass binary systems, resulting in a more powerful emission.
“Although GW170817 can be explained by other theories, we can confirm that a parent system of neutron stars with significantly different masses, similar to the PSR J1913+1102 system, is a very plausible explanation.
“Perhaps more importantly, the discovery highlights that there are many more of these systems out there – making up more than one in 10 merging double neutron star binaries.”