Plus you can learn more about what’s in our Solar System with our Top 10 Facts on the Sun and the Moon; the planets Earth, Venus, Mars, Jupiter, Saturn, Uranus and Neptune and the dwarf planet Pluto.

Mercury is the closest planet to the sun and the smallest planet in our Solar System. It is the first planet in the Solar System and is named after the Roman messenger god. This fascinating planet is filled with interesting facts, from its extreme temperature variations to its unique surface features. We’re going to take a look at the Top 10 Facts about Mercury and explore its intriguing features. So let’s get started!

1. Mercury is the closest planet to the Sun.

Mercury is the innermost planet in Earth’s solar system, which means it is closest to the Sun.

2. It is the second hottest planet in the Solar System.

Even though Mercury is the planet closest to the Sun it isn’t as hot as Venus.

Venus is 471°C whereas Mercury is 430°C during the day and -180°C at night.

Find out about the weather on Mercury, and other planets, in the video below.

3. Mercury is the smallest planet in the Solar System.

It’s only a little bit bigger than The Moon, and because of its small size – 2,439.7 km, it’s not the easiest of planets to observe through a telescope.

4. Mercury is a rocky planet.

Along with Venus, Earth, and Mars, Mercury is one of the rocky planets. It has a solid surface that is covered with craters. In fact the surface looks very much like the moon.

5. Mercury has a crater named after Dr Suess.

Mercury’s craters are named after famous artists and writers.

One of these craters is names Geisel after Theodor Seuss Geisel, better known as Dr. Seuss.

6. A day on Mercury takes 59 Earth days.

Because Mercury spins so slowly it takes 59 Earth days to make a full rotation.

7. Mercury’s year is just 88 Earth days.

Because Mercury is so close to the Sun it doesn’t take very long for it to orbit the sun. This makes the years on Mercury very short. This means if you lived there you’d celebrate New Year’s every 3 months.

8. Mercury has been visited by two spacecraft – Mariner 10 and MESSENGER.

Mariner 10 was an American robotic space probe launched by NASA on 3 November 1973, to fly by the planets Mercury and Venus. NASA’s Mariner 10 was the first spacecraft sent to study Mercury.

MESSENGER was a NASA robotic space probe that orbited the planet Mercury between 2011 and 2015, studying Mercury’s chemical composition, geology, and magnetic field.

9. Mercury is named after a Roman God.

The Romans believed that gods and goddesses were in charge of everything on Earth. Mercury is named after the messenger for their gods.

This name fits perfectly because The Roman God Mercury had wings on his helmet and shoes. He could travel very quickly from place to place just like the planet Mercury moves quickly around the sun.

10. Mercury’s surface has ice on it.

In 2012, NASA’s MESSENGER spacecraft discovered water ice inside some of Mercury’s craters.

Being so close to the sun, you might find it strange that Mercury could harbor any surface ice at all. But some parts of Mercury receives very little direct sunlight, and some craters remain constantly in the dark.

Let’s keep learning with our Top 10 Facts about Space and Top 10 Facts about the Solar System. Plus you can learn more about what’s in our Solar System with our Top 10 Facts on the Sun and the Moon; the planets Earth, Venus, Mars, Jupiter, Saturn, Uranus and Neptune and the dwarf planet Pluto.

Find out even more about Mercury…

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