It is just amazing to see how the validity of Einstein’s theories have been tested repeatedly and proven to be correct. Einstein did all of what he did in his mind, on the blackboard and on paper. No labs to test his ideas and no real means to verify his theory.
Neutron stars are very different from black holes. Neutron stars are produced from supernova, the explosion of massive stars, and are approximately 1 to 20 times the mass of our sun, but are made up of pure neutrons. The density of the neutron stars are very much greater than the density of atomic nuclei. This results in neutron stars being very compact. They are relatively small, about 25km in diameter (yes, smaller than Singapore).
Yesterday, 16th October 2017, the National Science Foundation held a press conference where they announced the detection of collisions between two neutron stars which is a few hundred million light years away from earth.
This collision generated gravitational waves, but more importantly, electromagnetic radiation in the visible range – i.e., light we can see. This light was detected by a scattering of observatories on earth and in space.
You can watch the entire announcement by following this video:
The light that was generated suggests that heavy metals like gold (Au) , silver (Ag) are present which essentially confirms that elements heavier than hydrogen and helium are only possible when there are massive super novae.
Just look around you. If you see a gold chain, a gold plated ornament, it means that that element was created in a star billions of years ago.
That and all of us on Earth are made of star stuff.