What is a galaxy's bulge?

1 Answer
Mar 31, 2018


It's the central part of a galaxy, where there is a much higher concentration of older stars, dust, and other luminous objects.


The reason it is denoted a bulge, is because the high luminosity stands out from the rest of the galaxy and looks like it is bulging outwards. Here's an artistic rendition that is probably a bit inaccurate, but illustrates the concept because it is fairly exaggerated.

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It is also commonly accepted that most galaxies contain a supermassive black hole which resides in this central bulge.