What Is a Black Hole?
A black hole is a region of space where gravity is so strong that nothing — not even light — can escape.
They're among the most fascinating objects in the universe.
How Strong Is a Black Hole's Gravity?
To escape Earth's gravity, you need to travel at 11.2 km/s (about 25,000 mph).
A black hole's gravity is so intense that even light — traveling at 300,000 km/s — can't escape once past the "event horizon."
Key Parts of a Black Hole
Singularity: The center, where matter is compressed to infinite density. Our physics breaks down here.
Event Horizon: The "point of no return." Cross it, and escape becomes impossible.
Accretion Disk: Material spiraling into the black hole, heated to millions of degrees, glowing brilliantly.
Jets: Some black holes shoot material from their poles at near-light speed.
Types of Black Holes
- Form when massive stars collapse
- Millions exist in our galaxy
- Found at galaxy centers
- Our Milky Way has Sagittarius A* (4 million solar masses)
- Recently discovered, formation unclear
Do Black Holes "Suck" Everything In?
Not really. If our Sun became a black hole (it won't — too small), Earth would keep orbiting normally. You'd have to get very close for extreme effects.
Black holes aren't vacuum cleaners. They're just very dense objects with strong gravity nearby.
Time Near Black Holes
Due to general relativity, time slows near massive objects. Near a black hole, time passes significantly slower than far away.
This is the basis for the "time dilation" in Interstellar.
Related Reading
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Explore mysteries of space in Black Holes: The Universe's Dark Secrets.