πͺ Space and stars πͺ The Sun and planets
Mercury
π In short
Mercury is the planet closest to the Sun and the smallest in the solar system. It's a small rocky planet with a surface full of craters, like the Moon. It goes around the Sun faster than any other planet, so its year is only 88 days!
π€© Did you know?
- Mercury is about 4878 kilometers across, roughly two-fifths the Earth's width.
- Mercury spins once about every 59 Earth days.
- A year on Mercury lasts 88 Earth days.
- Mercury has no moons.
π Find out more
π Very hot and very cold
By day Mercury is hot enough to melt lead, and at night it gets very cold, because it has almost no air to hold in the heat.
π A long day
Mercury spins very slowly, so daytime lasts a very long time. If you stood on Mercury, you'd see the Sun moving very slowly across the sky, looking much bigger than from Earth.
π‘ Full of craters
Mercury's surface is full of craters made by meteorites over millions of years, including a huge one called the Caloris Basin.
π― Few visits
Few spacecraft have visited Mercury, because getting there near the burning Sun is hard. They include Mariner 10, Messenger and BepiColombo.
πΈ More pictures
𧩠Test yourself
1 Which planet is closest to the Sun?
2 How many days does a year on Mercury last?
3 Mercury is about ?? kilometers across, roughly two-fifths the Earth's width.
4 Which picture shows βMercuryβ?
πͺ Discover more
π· Picture sources: Wikimedia Commons
- NASA/Johns Hopkins University Applied Physics Laboratory/Arizona State University/Carnegie Institution of Washington Β· Public domain
- NASA Β· Public domain
- Wikimedia Commons Β· Public domain
- NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington Β· Public domain
