Astronomers have a new way of detecting active black holes and of measuring how much matter they are sucking in. Scientists say that the new technique can use existing data from telescopes to identify these bright supermassive black holes at the centre of galaxies.
Lead author Jessica Thorne is a PhD student at the University of Western Australia node of the International Centre for Radio Astronomy Research. She says that active black holes are typically found in the largest galaxies in the Universe.
“The black holes we’re looking for are between a million and a billion times more massive than our Sun,” she says. “As they suck in matter from around them, the matter gets super-heated because of friction and becomes very, very luminous. And when they’re active, these black holes can outshine the rest of the galaxy.”
Despite their brightness, identifying such black holes has been challenging, requiring complex methods unique to different types of telescopes.
The new technique instead works on typical telescope observations, using an algorithm called ProSpect to model emissions from galaxies and black holes at different wavelengths of light. It has already been applied to existing observations of almost 700,000 galaxies, and using new telescopes like the James Webb Space Telescope and the Square Kilometre Array in Australia and South Africa, astronomers may be able to apply the technique to millions of galaxies at once.