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"What is a Planet?" icon

What is a Planet?

A planet is a large, round heavenly body that orbits a star and shines with light reflected from the star. Eight planets orbit the sun in our solar system. In order of increasing distance from the sun, they are: (1) Mercury, (2) Venus, (3) Earth, (4) Mars, (5) Jupiter, (6) Saturn, (7) Uranus, and (8) Neptune. Many nearly planet-sized objects, called dwarf planets, also orbit the sun. Dwarf planets include Pluto and Ceres. Since 1992, astronomers have discovered many planets orbiting other stars. 

This site describes what a planet is and has a link to an educator's guide.




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Kendra Wells
Kendra Wells (Faculty)
8 years ago
The photographs and information provided in this site is easily located and navigated. Information is provided in terms students will understand. Interactive features are a bonus!
Time spent reviewing site: 20 minutes
Robin Lynch
Robin Lynch (Student)
8 years ago
This explanation of planets is well-detailed without using a lot of technical jargon which makes it more accessible to students. I think that I would easily be able to simplify the information even further to teach to the lower grades in elementary education.