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Astronomy/Astronomy/Our Milky way way galaxy


Our Milky Way galaxy which is a spiral one that supposedly has a black hole at its center in which not even light can escape. My question is this: If that's the case then how come all the drawings or renderings of what our galaxy looks like, show it to be well illuminated at the center? I mean any stars near a black hole, their lights or rays would be absorbed by the black hole if not the whole star itself. That leads to another question, if you could please answer: Could a black hole suck in or absorb a whole star at once? Black holes and stars, both cannot be at the center of our galaxy, as I've already asked why is our galaxy depicted as being so well illuminated at its center? Thank you for the time in answering these questions.

Although no light can escape the interior of a black hole, even the most massive black holes are very small compared to the distances between stars, so it is actually much harder to shine a light in the direction of a black hole than in some random direction. As a result, almost all the light emitted by stars in the nucleus of the galaxy passes right through and out of the nucleus, and the presence of a black hole makes no measurable difference in the overall brightness of the galaxy's central region. That is why the center of our galaxy is just as bright as if there were no black hole there.

There are some stars that are close enough to the central black hole that their motion is strongly affected by it, but that just means they move around much faster than usual, and "orbit" within the region near the black hole at a speed fast enough to keep them from falling into it. Once in a while a near collision between two stars might change their motion in a way that allows one of them to pass much closer to the black hole, allowing it to pull some of their outer layers away; and once in a VERY great while one might come close enough to be completely torn apart. But although such things do happen they are very, very rare.

Even in that case, however, it is not likely that the star will just head right at the black hole and just disappear. It is far more likely that as it is torn apart its gas will spiral toward the black hole, forming an "accretion disk" surrounding the black hole's event horizon. In some galaxies (not as many as you might expect, as I am about to discuss a relatively rare event) there may be so much gas trying to spiral into the black hole that the gravitational compression of the gases heats them up to extremely high temperatures, and they emit huge amounts of light and even jets of near-light-speed material. The light and jets produced in this way cannot escape in the plane of the disk because there is so much material trying to fall into the hole that it blocks their escape; so they are only emitted toward the "poles" of the disk, at a perpendicular to its plane. Since there are so many galaxies in the Universe, even though this is a relatively rare situation, there are thousands and thousands of such accretion disks, and study of their characteristics provides clues to the nature of the black holes that create them. But as already noted, that is not something that is going on in our galaxy at the present time, and it is not likely that such an event will occur at any time in the next billion or so years.


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Courtney Seligman


I can answer almost any question about astronomy and related sciences, such as physics and geology. I will not answer questions about astrology and similar pseudo-scientific rubbish.


I have been a professor of astronomy for over 40 years, and am working on an online text/encyclopedia of astronomy, and an online catalog of NGC/IC objects.

Astronomical Journal, Publications of the Astronomical Society of the Pacific (too long ago to be really relevant, but you could search for Courtney Seligman on Google Scholar)

I received a BA in astronomy and physics and a MA in astronomy, both from UCLA. I was working on my doctoral dissertation when I started teaching, and discovered that I preferred teaching to research.

Awards and Honors
(too long ago to be relevant, but Phi Beta Kappa and Sigma Xi still keep trying to get me to become a paying member)

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