🪐 Planet
Mercury
The smallest planet, and the closest to the Sun.
- Size
- 4,900 km across, 38% as wide as Earth
- A day lasts
- 176 Earth days
- A year lasts
- 88 Earth days
- Moons
- None
- Average temperature
- 167 °C
- Gravity
- 0.38× Earth’s
- From the Sun
- 58 million km
📍 Where is it now?
Seen against the stars of Libra, 100 million km from Earth. Its light takes 6 minutes to reach us.
Did you know?
- One day on Mercury, from sunrise to sunrise, lasts longer than its whole year.
- It has almost no air, so its nights fall to about −180 °C even though it is closest to the Sun.
Compare Mercury with EarthSide by side, to scale, in the app
More NASA photos of MercuryStraight from NASA’s image library, in the app
Explore more
All of solar system
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.
Uranus
The ice giant that rolls around the Sun on its side.