What is Binary black hole?
{{More sources}}[[File:BBH gravitational lensing of gw150914.webm|thumb|Computer simulation of the black hole merger [[GW150914]]. The background is distorted as the intense gravity from the merger causes [[gravitational lensing]].]] A Binary Black Hole (often abbreviated BBH), are two [[Black hole|black holes]] in close orbit around each other. The two black holes will eventually merge into one releasing a large amount of [[Gravitational wave|gravitational waves]]. == Discovery == For years the existence of binary black holes was only theoretical. Proving they exist was a challenge due to the nature of black holes. Although if two black holes were to ever merge this would cause a significant amount of gravitational waves to be released. The existence of binary black holes (and gravitational waves themselves) was proven when on September 2015, [[LIGO]] detected [[GW150914]].<ref>{{Cite journal|last=Castelvecchi|first=Davide|last2=Witze|first2=Alexandra|date=2016-02-11|title=Einstein's gravitational waves found at last|url=https://www.nature.com/articles/nature.2016.19361|journal=Nature|language=en|doi=10.1038/nature.2016.19361|issn=1476-4687}}</ref> == References == {{reflist}} {{Black holes}} [[Category:Black holes]]