Planet Facts For Kids
When I was younger, it was said that there were 9 planets in our solar system. The planets were Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto going around the sun. Later, I came across a mnemonic for it. My Very Educated Mother Just Served Us Nine Pizzas. However, since that time scientists have decided that we have eight planets in our solar system and that Pluto is a dwarf planet, and actually they have found larger rocks in the area of Pluto than Pluto itself. On this page of planet facts for kids, I have decided to include Pluto so that you know why it is in some lists.
Here is a video you might like to watch and then there is some information about each planet.
Mercury is the closest planet to the sun. It is also the smallest of the planets. It is incredibly hot there as it is just 36 million miles from the sun.
It is named after the Roman god Mercury who is the messenger of the gods.
Two spacecraft have flown past Mercury gathering information. One was called Mariner 10 and this flew past Mercury twice, once in 1974 and then again in 1975. Then in 2004 MESSENGER was sent. This orbited Mercury 4000 times before running out of fuel and crashing into the planet in 2015.
Venus between Mercury and Earth and so will still be much hotter than Earth.
It is named after the Roman god of love.
It is the brightest object in the sky after the sun and the moon.
Whereas the Earth rotates once a day, Venus takes 243 days to rotate on its axis. It actually goes quicker than this around the sun, taking 224.7 Earth days to make its journey.
Venus also rotates in the opposite direction than the Earth does, which means that the sun would seem to rise in the west and set in the east.
Venus is often referred to as either the morning star or the evening star, especially in poetry.
Of course, this is our planet.
From space, it looks blue because of all the sea and also the water vapour covering the land areas.
About two-thirds of the planet’s surface is water.
Earth is 93 million miles away from the sun and a quarter of a million miles from the moon. In kilometres, that is 150 kilometres from the sun and about 384,400 km from the moon. These are approximate distances as it changes throughout the year.
The Earth goes around the sun once a year.
The moon goes around the Earth every 27.3 days. This is known as a lunar month.
The diameter of the Earth at the Equator is 7928 miles, or 12,760 kilometres.
Mars comes after Earth.
It is named after the Roman god Mars the god of war because it looks red sometimes in the sky and this reminded people of the blood that you get in battles.
It is often called the red planet and can be spotted in the sky with the naked eye, that is without using a telescope.
Mars is much smaller than Earth. Its diameter is about half of the Earth’s.
Mars rotates once in 24 hours 39 minutes, so the length of its day is almost the same as Earth’s. It has two moons, called Phobos and Deimos. They are not round like the moon but irregular.
After Mars we get Jupiter. This is a very big planet, 1000 times smaller than the sun but two and a half times bigger than all of the other planets in the solar system put together.
Jupiter and Saturn are both gas giants.
Jupiter has an area called the Great Red Spot – you can see it on photographs. There are constant storms here. This area alone is 1.3 times as wide as the earth.
Jupiter is made up of hydrogen and helium as well as other elements which possibly gives it a rocky core. Jupiter has many moons, at least 74, including four that were discovered by Galileo Galilei in 1610. The largest of these is called Ganymede and it has a diameter that is larger than the planet Mercury.
Next is Saturn which has amazing rings around it. These rings consist of small rocks that held in a particular orbit.
Saturn is another gas giant, It is the outer layer that is made of gas, The core is probably iron, nickel and rock, and then there is a layer of metallic hydrogen, with hydrogen and helium surrounding that.
Saturn also has a number of moons, at least 62. 53 of the moons are officially named. The biggest is called Titan and that is bigger than the planet Mercury.
Uranus is even further away. Uranus, along with Neptune are known as ice giants, as their interiors are filled with ice and rocks.
Uranus is unique in that it rotates on its side.
It has wind speeds up to 900 km an hour.
It is also the only planet that has been named after a Greek god rather than a Roman god.
Uranus has 27 named moons and 24 are named after characters in Shakespeare plays and 3 after characters in a poem by Alexander Pope. One of these Ariel appears both in The Tempest by Shakespeare and in the poem by Pope.
Voyager 2 was the closest to Uranus on its voyage on January 24, 1986.
Neptune is named after the Roman god of the sea. It is now accepted as being the farthest known planet from the sun. Neptune’s atmosphere is made up of hydrogen and helium but its interior is made up of ices such as water, ammonia and methane. Its wind speeds reach up to 2100 km an hour!
In 1613 Galileo noticed Neptune but he thought it was just another star. It is thought that if he had noticed it a few days earlier when the sky was clearer and tracked it he would have realised it was a planet.
Voyager 2 flew past Neptune on 25th August 1989.
And as I said before Pluto is no longer classified as a planet, but you will often see it in a list of planets, especially if the article or book was written before August 2006.
Pluto has a strange orbit around the sun so sometimes it is nearer the sun than Neptune.
Other videos you might like to see:
Planet facts worksheets
Here are some free worksheets about planets that you might find useful.
And here are 15 planets worksheets – designed for children with English as a second language but useful for all.