The Circumnuclear Disc is a clumpy ring of gas and dust circling the black hole at the centre of the Milky Way, the inner edge of the Galaxy’s gas reservoir.
At a glance
| type | nebula |
|---|---|
| distance from the Sun | 26,700 light-years (8.18 kpc) |
| its light left it | 26,700 years ago |
| size in the piece | about 29 light-years acrossmodel |
Read off the piece’s own catalogue, the same values it draws with. Model marks a property of the piece’s galaxy model rather than a measurement.
About Circumnuclear Disc
Around Sgr A*, the black hole at the Galactic Centre, lies a ring of dense molecular gas and dust, tilted and clumpy, with a hollow middle. Its inner edge is lit and ionised by the cluster of hot, massive stars that surrounds the black hole, and inside the cavity streamers of ionised gas, together called the Minispiral, fall inward on curving paths.
Visible light from the centre is almost completely absorbed by the dust between us and it, so everything known about the disc comes from radio, millimetre and infrared observations: molecular lines that map the dense gas and its rotation, and infrared glow from warm dust. The ring is thought to be a reservoir that, over time, feeds gas toward the black hole and the young stars around it.
What you see in the piece
In visible light from the Sun it is lost behind the dust of the inner Galaxy; switch to infrared or radio, or fly to the centre, and the ring appears around Sgr A*.
Measured or modelled
The disc’s lifetime, whether it is a stable ring or a passing arrangement of clumps, and how much gas it actually delivers inward are debated. Its shape and extent here are modelled.
Questions
What is the Circumnuclear Disc?
It is a ring of molecular gas and dust orbiting the supermassive black hole at the centre of the Milky Way, with a hollow centre where ionised gas streams inward.
How far away is the centre of the Milky Way?
The Galactic Centre, and the Circumnuclear Disc around it, is about 26,700 light-years (8.18 kpc) from the Sun.