It is now widely expected that the detection of gravitational waves using the Ligo (Laser Interferometer Gravitational-wave Observatory) observatories will be announced today at 15:30 GMT at a press conference that has been called at the National Press Club, Washington DC.
Although everything is still rumour at this point, the “details” have begun to leak. If they are true, then they certainly explain a few things that seemed confusing at first. In particular, they suggest that the gravitational waves were produced by a pair of highly unusual black holes colliding.
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The black hole news on its own would be a great discovery, but combined with the detection of the gravitational waves it is an academic double whammy that has astronomers and physicists reeling with excitement.
Black holes are the most mysterious objects in the universe but one thing we do know is that they come in two main varieties. Stellar black holes are those that form after stars explode, and typically have masses of between 3-15 times that of the sun. At the other end of the scale there are supermassive black holes that squat in the centre of galaxies and possess masses of millions and billions times that of the sun.
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However, the black holes expected to be announced today are said to have masses of 29 and 36 suns. These are highly unusual masses – above the usual stellar black hole regime but far below the supermassive ones – and may explain why researchers were confident that it wasn’t a test signal injected into the data.
It also explains the sudden appearance in early January of a number of theoretic