Getting a clearer view of supermassive black holes at the centres of galaxies12 December 2009
Most people have heard of black holes: when a big chunk of matter (like a star) no longer has sufficient internal pressure to withstand its own gravity it can collapse and suck in anything that comes past a line called its event horizon. They’re weird, freaky things, to be sure, but theory predicted them, and astronomy has found enough evidence that it’s treated as certain that we can see a bunch of them out there.
Supermassive black holes – in addition to being a great song by Muse – are enormous black holes thought to exist at the centre of most, if not all, galaxies. There are signs of them, and a few models for how they might form.
Scientists have recently been able to better see what’s happening at the edge of some of these supermassive black holes. They’ve done this by cleverly using two nearby telescopes, the Keck telescopes in Hawaii. This technique, called interferometry, allows them to remove the effects of the stuff – much of which is creating a lot of radiation “noise” – that’s happening nearby.