Event horizon

High school (ages 12+)
Space & Astronomy

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/event-horizon

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the spacetime boundary type?A null hypersurface beyond which causal influence cannot propagate outwards
2. What is the escape velocity condition?Equals the speed of light at the event horizon
3. Why can't anything get out of an event horizon?The gravity inside the event horizon is so strong that the speed needed to escape is faster than light. Because light can’t travel that fast, nothing can leave once it crosses the horizon.
4. Who first imagined objects that could trap light?John Michell in 1784, and Pierre‑Simon Laplace, both thought about very heavy stars that could pull light so strongly that it would never escape.

Null Hypersurface: A boundary in spacetime where light rays travel along the boundary itself.
Causal Disconnection: A state where events inside a boundary cannot influence events outside it.
Information Paradox: The theoretical conflict between quantum mechanics and general relativity regarding information loss in black holes.
Gravitational Singularity: A point in spacetime where the laws of physics break down, predicted at the center of a black hole.