The Milky Way is a barred spiral galaxy, with a supermassive black hole at its center. Here

As it is a barred spiral galaxy, it has a central bar-shaped structure composed of stars.Here

So my questions are -:

  • Do the bar and supermassive black hole overlap or cross each other?
  • Do the stars from the bar get sucked inside the supermassive black hole?

2 Answers 2


Lets get a sense of scale. The bar is about 30000 light years long, and contains the central bulge of the galaxy, a roughly spherical mass of stars with a diameter of 10000 ly. It's big.

The supermassive black hole is pretty big for a black hole, but only about 80 light seconds across. Compared to the size of the bar, it is tiny.

The supermassive black hole is found at the centre of the bulge, at the centre of the bar, and entirely within it.

Sometimes a star does fall into the black hole. The black hole is currently inactive, that means that there is not much matter falling in every year. Each year, roughly 1/10000 of the mass of the sun falls into the black hole. This is mostly matter from the solar winds of nearby stars.

  • $\begingroup$ Nice answer, whichy I think could be improved by adding some links to sources and/or further reading for some of the things you mention (like e.g. the infall rate into the Galactic SMBH). $\endgroup$
    – Thriveth
    Jul 28, 2016 at 16:01
  • 2
    $\begingroup$ The capture rate can be found at wikipeida, which references arxiv.org/pdf/1307.5845v2.pdf, which in turn references iopscience.iop.org/article/10.1086/375145/pdf $\endgroup$
    – James K
    Jul 28, 2016 at 16:54
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    $\begingroup$ The size figures can also be found on wikipedia, and by calculating the radius of 4.1million solar mass black hole. $\endgroup$
    – James K
    Jul 28, 2016 at 16:56

Just to add to James' answer, we have amazing images of the stars very near to the BH at the galactic core. One star in particular, called S2, has had its complete orbit mapped.


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