The structures slow down the gas until it falls to a galactic centre
Gas-guzzling supermassive black holes, known as quasars, are fed by their host galaxy’s spiral arms scooping up gas for them to devour, according to a new set of computer simulations which looked at the gas flow throughout the whole galaxy, rather than just the region around the black hole.
“The light we observe from distant quasars is powered by gas falling into supermassive black holes and getting heated up in the process,” says Claude-André Faucher-Giguère from Northwestern University.
Quasars can swallow up to 10 solar masses of material a year, but astronomers have struggled to account for what funnels the gas towards the central black hole.
“Our simulations show that galaxy structures, such as spiral arms, use gravitational forces to ‘put the brakes on’ gas that would otherwise orbit the galaxy centres forever,” says Faucher-Giguère. www.northwestern.edu