Astronomers have previously theorised that a thick ring of dust, known as a torus, surrounds the supermassive black holes at the centre of huge galaxies

Astronomers have previously theorised that a thick ring of dust, known as a torus, surrounds the supermassive black holes at the centre of huge galaxies
Mysterious features seen in light emitted from active galactic nuclei may be due to partial obscuration by dust clouds
A recent study has revealed a link between the mass of a galaxy’s supermassive black hole and its stellar history