1. Stellar Black Holes:
These are formed when massive stars exhaust their nuclear fuel and collapse under their own gravity. Stellar black holes can have masses several times greater than that of our Sun, typically ranging from a few to tens of solar masses.
*Example*: The stellar black hole at the center of our Milky Way galaxy, known as Sagittarius A*, has a mass of about 4 million solar masses.
2. Intermediate Black Holes:
These fall between stellar black holes and supermassive black holes in terms of mass. Intermediate black holes are thought to form through various mechanisms, such as the accumulation of mass from stellar black holes or the direct collapse of large gas clouds.
*Example*: An intermediate black hole candidate within the galaxy M82 has an estimated mass of several hundred thousand solar masses.
3. Supermassive Black Holes:
These are the largest and most massive black holes known to exist. They reside at the centers of most large galaxies, including our own Milky Way. Supermassive black holes can have masses ranging from millions to billions of times that of our Sun.
*Example*: The supermassive black hole at the center of the Milky Way, Sagittarius A*, is estimated to have a mass of about 4 million solar masses, while the supermassive black hole at the heart of the galaxy M87 is believed to have a mass of around 6.5 billion solar masses.
It's worth noting that astronomers are constantly discovering new black holes, and the boundaries between these categories can sometimes be blurred. The exact mechanisms behind black hole formation and growth remain an active area of research in astrophysics.
