How do you find a black hole?

The video explains the presence of a supermassive black hole at the center of our galaxy. It discusses how observing the orbits of stars around the galaxy's center can provide evidence of the black hole's mass and volume. The concept is compared to how planets orbit the sun due to gravity, allowing for mass measurement. The video also touches on the differences between local characteristics and the universe's expansion, noting that the center of our galaxy does not exhibit net expansion.

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