Q&A: Galaxies, Galaxy Clusters, AGN, and Quasars

Q:
Could the supermassive black hole in Perseus be a supermassive "white" hole? In the Chandra X-ray image, the point is white, and in an X-ray photo, the white means that we can't pass the object?

A:
The object at the center of the X-ray image acts like a black hole, i.e. a very massive, very dense object that light cannot escape from. For example, the jets of material blown out by the object at the center of the galaxy should come from a black hole. Astronomers cannot think of any other object that can cause jets which are this large.

The black hole shows up as a white dot because of the hot, dense gas spinning around a disk around the black hole. This hot gas glows in X-rays. We don't see X-rays from the black hole itself, which would look black in this image, but is far too small to be detectable in this image.

It is important to note that the X-rays and jets are not coming from the black hole itself, but from the surrounding matter, likely an accretion disk, in some way that we do not yet understand.