The first-ever observation of two neutron stars crashing into each other, and the massive scientific bounty it revealed, is the journal Science’s 2017 Breakthrough of the Year.
The collision 130 million light years away “confirmed several key astrophysical models, revealed a birthplace of many heavy elements, and tested the general theory of relativity as never before,” Science said in announcing its Breakthrough of the Year.
The most studied astronomical event ever (Science points out that 3,674 researchers from 953 institutions worked on a single paper summarizing the merger and its aftermath) beat out other breakthroughs from the year in gene therapy, cancer drug development, gene editing, and new information about a skull in Morocco that pushed back the human origin timeline.
The overall significance of the whole thing is pretty esoteric, particularly in the physics/nature of the universe aspect of it. For example, it’s a big deal in physics that the neutron star collision provided a welcome reinforcement of Albert Einstein’s general theory of relativity, confirming that gravitational waves travel at the same speed as light.
But there were also some more easily understood basic science advances from seeing this cosmic event. For example, the crash provided scientists with a better understanding of the origin of many heavy elements in the universe, including new knowledge of where gold, platinum, uranium and mercury came from. Scientists were able to see evidence of some newly-forged materials in the fallout that confirmed what they had expected was the source for these metals.