Science
What is an eclipse?
An eclipse happens when one space body passes into the shadow of another, or blocks it from view. A solar eclipse occurs when the Moon passes between Earth and the Sun; a lunar eclipse when Earth's shadow falls on the Moon.
See it, don’t just read it.
Watch a 2-minute lesson with voice + animation that explains an eclipse.
Key things to understand
- 1It's an alignment where one body blocks or shadows another.
- 2Solar eclipse: the Moon blocks the Sun from part of Earth.
- 3Lunar eclipse: Earth's shadow falls across the Moon.
- 4They happen only when Sun, Earth, and Moon line up closely.
- 5A total solar eclipse briefly turns day to twilight.
Frequently asked questions
- What's the difference between a solar and lunar eclipse?
- In a solar eclipse the Moon blocks the Sun; in a lunar eclipse Earth's shadow falls on the Moon, often turning it reddish.
- Why don't eclipses happen every month?
- The Moon's orbit is tilted, so the Sun, Earth, and Moon only line up precisely enough a few times a year.
- Why is it dangerous to look at a solar eclipse?
- The Sun's intense light can permanently damage your eyes; you need special eclipse glasses, not ordinary sunglasses.