🌙 Moon
Triton
Neptune’s big moon, which circles the wrong way.
- Size
- 2,700 km across, 21% as wide as Earth
- Goes round Neptune
- every 5.9 Earth days
- Discovered
- 1846, by William Lassell
Did you know?
- It orbits in the opposite direction to Neptune’s spin, a sign it was probably captured from far away.
Compare Triton with EarthSide by side, to scale, in the app
More NASA photos of TritonStraight from NASA’s image library, in the app
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All of solar system
Mercury
The smallest planet, and the closest to the Sun.
Venus
The hottest planet, hidden under thick clouds.
Earth
Our home, the only world known to have life.
Mars
The red planet, with the tallest volcano in the solar system.
Jupiter
The biggest planet, with a storm larger than Earth.
Saturn
The ringed giant, light enough to float in water.