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Course: Middle school Earth and space science > Unit 1
Lesson 3: The solar systemThe solar system
Review your understanding of the solar system in this free article aligned to NGSS standards.
Key points:
- Our solar system formed from a huge cloud of gas and dust about
billion years ago. It consists of the sun, eight planets and their moons, an asteroid belt, and other celestial bodies such as comets. - The four planets closest to the sun—Mercury, Venus, Earth, and Mars—are called the inner planets. These planets have thin atmospheres, solid surfaces, few or no moons, and no rings.
- The four planets farthest from the sun—Jupiter, Saturn, Uranus, and Neptune—are called the outer planets. These planets have thick atmospheres, no solid surfaces, and many rings and moons.
- The inner and outer planets are separated by the asteroid belt, a ring-shaped region containing many rocky bodies called asteroids.
- Comets are dusty, icy bodies that orbit the sun beyond Neptune. Both comets and asteroids are much smaller than planets.
Want to join the conversation?
- Why are all of the biggest planets made up of gas and liquid?(55 votes)
- It is probably because the gas and liquid substances weren't able to be combined to create a planet nearby the sun, so they eventually moved outwards and became the gas giants we know.(44 votes)
- Which is the biggest planet?(7 votes)
- The biggest planet in our solar system is Jupiter. UniverseToday.com gives these measurements: “Jupiter (69,911 km / 43,441 miles) – 1,120% the size of Earth”.
I hope this helps! :)(50 votes)
- Jupiter (69,911 km / 43,441 miles) – 1,120% the size of Earth”.(14 votes)
- very helpful thanks let me add on Jupiter Is Massive: ...
Jupiter Cannot Become A Star: ...
Jupiter Is The Fastest Spinning Planet In The Solar System: ...
The Clouds On Jupiter Are Only 50 km Thick: ...
The Great Red Spot Has Been Around For A Long Time: ...
Jupiter Has Rings: ...
Jupiter's Magnetic Field Is 14 Times Stronger Than Earth's: ...
Jupiter Has 67 Moons:(18 votes)
- I wonder who discoverd the solar system(10 votes)
- As Alex said, humans have known some things about the solar system since they started looking up. Copernicus popularized the fact that it’s a solar system, though: that the planets go around the sun instead of everything going around the earth.
Does that help?(24 votes)
- how are comets formed?(10 votes)
- According to NASA, "Comets are frozen leftovers from the formation of the solar system composed of dust, rock, and ices."(16 votes)
- why does the comets have tails?(10 votes)
- It's simply because it is the comet's particles being burnt as it moves near the sun.(14 votes)
- and guys how do we have a solar eclipse if the moon is smaller than the earth it's super tiny in comparison to the sun someone explain?(6 votes)
- The moon is closer than the sun. You can also block the sun with your hand. Clearly, the sun is larger than your hand but it can still block the sun because your hand (like the moon) is much closer to your eyes than the sun is.(14 votes)
- How did the Solar system originate?(6 votes)
- gravity pulled a cloud of gas so hared it became the sun and then the gravity from the sun made the solar system we now today🌌🪐🌍🌑🌞(11 votes)
- How fast can a Comet travel?(8 votes)
- A comet's top speed is 17,500 miles per hour, which in kilometers is 2816 kilometers per hour(6 votes)
- If one of Jupiter's moons has more mass than mercury why is it still considered a moon?(6 votes)
- Because the moon was captured by Jupiter and is orbiting around it so it is considered a moon.(8 votes)