Chapter 1
The anatomy of a black hole
Chapter 2
The four cosmic families
Chapter 3
Extreme physics and spaghettification
Chapter 4
Photographing the invisible
Ch 2 · The four cosmic families

hue Intermediate black holes bridge the gap between small stellar ones and giant supermassive ones.
hue Black Hole Cosmic Families
Four cosmic families, four cosmic families, supermassive giants holding it down!

hue Supermassive black holes contain millions or billions of solar masses and sit at the hearts of galaxies.
Quiz
Which hypothetical black holes are thought to have formed in the first second of the universe?
Fun Fact
Sagittarius A* mass: Our galaxy's central black hole, Sagittarius A*, weighs as much as 4.3 million of our Suns combined.
Quiz
Approximately how many solar masses is Sagittarius A*, our galaxy's central black hole?
Glossary
black hole (noun)
A region of spacetime where gravity is so strong that nothing, not even light, can escape. Sagittarius A is a supermassive black hole located at the center of the Milky Way galaxy.
A region of spacetime where gravity is so strong that nothing, not even light, can escape. Sagittarius A is a supermassive black hole located at the center of the Milky Way galaxy.
