Welcome to our Planet Facts library. On this page you can access one of the largest collections of facts about the planets on the internet. This is the perfect resource for students, teachers or anyone who wants to learn about all the planets in our solar system. We hope you find these facts about planets interesting, mind-blowing and educational. You can begin to explore our planet facts library by scrolling down and choosing a section.
Our Planet Facts category is separated into different sections. Each section is about a specific planet in our solar system. For example, we have a section about the planet Earth, Mercury and Venus. We're constantly updating our planet facts, if you can't find the information you're looking for you should check back at a later date. You can also contact us with your requests, and we'll add it to one of our future updates.
Each of the currently available planet facts sections are available below, in alphabetical order.
In this search you'll learn about the planet Earth. You'll learn how far the Earth is from the sun, what moons orbit Earth, how big Earth is, how long ago the Earth formed and other facts about the planet Earth.
In this search you'll learn about the planet Mercury. You'll learn how far the Mercury is from the sun, how big Mercury is, how long ago the Mercury formed and other facts about the planet Mercury.
In this search you'll learn about the planet Venus. You'll learn how far the Venus is from the sun, how big Venus is, how long ago the Venus formed and other facts about the planet Venus.
Our solar system formed about 4.6 billion years ago. There are currently eight known planets in our solar system. These planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. There are 185 known moons (natural satellites) orbiting these planets. Jupiter has the most with 79 moons and Earth has the least with one moon, Mercury and Venus have no known moons.
All eight planets orbit the sun. The sun is a main-sequence star in the center of our solar system. All planets orbit the sun in a counterclockwise direction when viewed from the north pole of our sun. The shortest orbital period is Mercury, it only takes about 88 Earth days to fully orbit the sun. The longest orbital period is Neptune, it takes over 164 Earth years to completely orbit the sun.
Between 1930 and 2006, Pluto was considered the ninth planet, but the International Astronomical Union in 2006 formally defined the term planet, effectively demoting Pluto to a dwarf planet.