ESO's GRAVITY instrument on the Very Large Telescope (VLT) Interferometer has been used by scientists from a consortium of European institutions, including ESO , to observe flares of infrared radiation coming from the accretion disc
around Sagittarius A*, the massive object at the heart of the Milky Way.
Although it's thought that supermassive black holes can grow indefinitely, there is a theoretical maximum that it will be able to grow by means of the conventional accretion disc
method, where gas in close proximity to the supermassive black hole becomes gravitationally attracted, passes the photon sphere and accretes into a disc as the material spirals into the black hole-beyond its event horizon (the boundary beyond which light cannot escape).
The black hole used to be fueled by galactic material such as gas and dust, which fell inward and created a spinning disk of material known as an accretion disc
. The black hole's strong gravity accelerated the material and heated it to millions of degrees, with the material sending out huge jets.
You see, black holes have normally been indicated by their accretion disc
- a collection of primarily stellar gases and space dust that orbit around it, and from where this matter is sucked into the black hole itself.
Since the material carries substantial angular momentum, it does not settle on the primary immediately, but forms an accretion disc
around the white dwarf.
Such baryonic jets, composed by heavy matter, are more likely to be powered by the accretion disc
rather than the spin of the black hole.
"If a black hole is spinning, it drags space and time with it and that drags the accretion disc
, containing the black hole's food, closer towards it.
Instead it orbits the hole, approaching gradually through an accretion disc
-- a sequence of circular orbits of decreasing size.
Frank Stefani have shown that the helical MRI very much applies to the Keplerian rotation profile if only the circular magnetic field is produced not entirely from the outside but at least partly from within the accretion disc
The short duration and shallow nature of the eclipses suggests that these are grazing eclipses of the accretion disc
, with the binary system being only slightly above the critical inclination for eclipses to occur.
These black holes rapidly pull in gas and dust which forms an "accretion disc
" and heats up causing the material to emit X-rays.