Solar System – Inner Planets
2 Minutes
Solar system inner planets for kids: explore the Sun, Mercury, Venus, Earth, and Mars with Casey the astronaut. A short science lesson in English.
- What the solar system is and how the Sun gives us energy
- Mercury's 88-day orbit and why Venus is even hotter
- Earth's moon and orbit, and research on Mars, the Red Planet
What this lesson teaches
The inner planets are the four planets located closest to the Sun in our solar system, consisting of Mercury, Venus, Earth, and Mars. These worlds circle an important star called the Sun, which provides the bright light and heat energy necessary for life to exist on Earth.
The Sun and the solar system
The Sun is a very hot and bright star situated at the center of the solar system. Earth and seven other planets revolve around this star on regular paths. The solar system is made up of all these planets together with the Sun. The Sun supplies a great amount of energy to the system, which serves as the primary reason living organisms are able to survive on Earth.
Mercury
Mercury is a tiny planet that occupies the position closest to the Sun in the solar system. Because it orbits so close to the star, it completes a full revolution around the Sun in just 88 days. Mercury reaches very high temperatures due to its close distance to the Sun, although another planet in the inner solar system is even hotter.
Venus
Venus is the second planet moving outward from the Sun. It takes 224 days for Venus to complete its journey around the Sun. Even though it is farther away from the Sun than Mercury, Venus is hotter than Mercury. People watching from Earth can easily observe Venus shining brightly in the sky during both the morning and the evening.
Earth and Mars
- Earth is the third planet from the Sun, taking 365 days to go around it, and it has one moon orbiting around it.
- Earth is the planet where we live, and it remains the only planet in the solar system that supports life.
- Mars is the fourth planet from the Sun and is commonly referred to by people as the Red Planet.
- Mars shares many similarities with Earth, which has led researchers to carry out intense studies in the hope of settling there.