In the Solar System
Mercury
The smallest planet and the nearest to the Sun, a cratered ball of rock a little larger than the Moon with a metal core taking up some 60% of its mass. It has almost no atmosphere, so the day side reaches about 430 °C while the night side falls to −180 °C, and there is water ice in the floors of polar craters the sunlight has never entered. It goes round the Sun in 88 days and turns three times on its axis for every two of those years.
- Radius
- 2,440 km
- Turns once in
- 58.6 d
Everything the map shows is worked out in your browser from published orbital data - nothing on it is a stored picture of where things were.