Two neutron stars colliding 130 million light years away is the biggest news in astronomy since we were sunk by the discovery of gravitational waves. Why? Read on to find out.
#1 Neutron stars colliding explains how gold is made
Gold, uranium, iodine – all of the heavy elements require massive forces at work to smash together all of the neutrons and protons in these atoms. It’s long been thought that neutron stars colliding would be one way that these elements may have been forged, and finally, astronomers have observed this happening. It took the super sensitive US and European gravitational wave detectors LIGO and Virgo to detect the signals from the stars, then savvy astronomers skewed their telescopes to observe the collision in progress (actually, it happened 130 million years ago, but it took that long to reach us). It’s true, we are all made of stardust.
#2 The light flash was brighter than a billion suns
So don’t look at it with the naked eye. Astronomers viewed the extraordinarily powerful light burst from the collision using the Zadko Telescope, operated by UWA’s School of Physics and the ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav), which monitored the explosion for four days.
#3 Gravitational waves were only detected for the first tame last year
First predicted by Einstein, the existed of gravitational waves was big news in astronomy. It takes a huge event to create detectable gravitational waves and these had come from the merger of two massive black holes 1.3 billion years ago. For more on gravitational waves check out this great explainer from @verisatum on yt.
#4 The discover of neutron stars colliding opens up a lollapalooza of theory for astronomers
Implications of today’s results are important for gravity theory, nuclear physics, stellar properties, stellar evolution, observational astronomy to name a few, says astronomer and science communicator @astrokatie
#5 Many waves, many ways
As well as the gravitational waves, many other signals were detected from the neutron stars colliding. “When black holes collide, the only thing we can detect is gravitational waves, everything else is swallowed inside,” says one of the astronomers involved, Prof. Avishay Gal-Yam of Weizmann’s Particle Physics and Astrophysics Department. “But neutron stars are relatively lighter than black holes, so when they collide and merge, a small part of their mass and radiation does escape and can be detected along with gravitational waves.” By observing the glowing radiation from the neutron stars colliding, astronomers we able to confirm the theory that heavy elements formed in just these kinds of rare collisions.
“This theoretical prediction had been made at least half a century ago, and now we finally have evidence that this might indeed have been the case,” Gal-Yam says. “Every element in nature emits and absorbs light in a different part of the spectrum, and that’s how we could tell which elements had emitted the detected radiation.”
“Our findings suggest, among other things, that every atom of iodine on Earth, including the iodine you put on your wound, had arrived here in the distant past from a merger of neutron stars.”
– Heather Catchpole
Author: Heather Catchpole
Heather co-founded Careers with STEM publisher Refraction Media. She loves storytelling, Asian food & dogs and has reported on science stories from live volcanoes and fossil digs