FIND IT TONIGHT · BANGKOK
Mercury in numbers
- 0.38 × Earth
- Width
- 176 Earth days
- One day
- 0
- Known moons
- 430 °C
- Daytime surface, hot enough to melt lead.
- −180 °C
- The same ground at night, with no air to hold the heat.
- 88 days
- One trip around the Sun, the fastest of any planet.
WORTH KNOWING
The smallest planet, and the hardest to catch.
Mercury never strays far from the Sun in our sky, so you only see it low in the twilight, just after sunset or just before sunrise, a few weeks at a time.
Its craters look a lot like the Moon's. Water ice may hide in craters near its poles, where sunlight never reaches the floor.
Who has been there
- 1974–75Mariner 10Three flybys; first close-up pictures.
- 2011–15MESSENGERFirst spacecraft to orbit Mercury.
- 2018 →BepiColomboESA and JAXA mission sent to orbit Mercury.