1. Unit 12 Lesson 1 What Objects Are Part of the Solar System?

2. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
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3. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
Earth, other planets, and the moon are part of a solar system.
A solar system is made up of a star and the planets and other space objects that revolve around it.
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4. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
A planet is large, round body that revolves around a star, which, in our solar system, is the sun.
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5. The Solar System There are eight planets in our solar system.
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Solar System
There are eight planets in our solar system.
The planets in our solar system are very far from one another.
The orbits of the planets are oval-shaped, or elliptical.
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6. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
All the planets rotate, or spin, around an axis, which is an imaginary line that goes through the center of the planet.
Earth rotates once on its axis every 24 hours, or the length of one day on Earth.
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7. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
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8. Mercury The Inner Planets
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Inner Planets
Mercury
Planets scavenger hunt game
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9. Venus The Inner Planets
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Inner Planets
Venus
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10. Earth The Inner Planets
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Inner Planets
Earth
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11. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Inner Planets
Mars
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12. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Inner Planets
The four inner planets are Mercury, Venus, Earth, and Mars.
The inner planets are
Very dense and rocky.
Have thin atmospheres
Have small diameters.
Have large, solid cores
Have few moons.
Their revolution times are short.
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13. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Inner Planets
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14. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Inner Planets
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15. The Outer Planets Jupiter
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Outer Planets
Jupiter
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16. The Outer Planets Saturn
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Outer Planets
Saturn
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17. The Outer Planets Uranus
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Outer Planets
Uranus
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18. Neptune The Outer Planets
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Outer Planets
Neptune
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19. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Outer Planets
The planets farthest from the sun are Jupiter, Saturn, Uranus, and Neptune.
These planets are known as gas giants, as
They are huge.
Made mostly of gases.
They don’t have a solid surface.
Their cores are very small.
All have many moons and ring systems.
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20. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Outer Planets
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21. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Outer Planets
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22. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Outer Planets
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23. Compare Inner and Outer Planets
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
Compare Inner and Outer Planets
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24. Compare Inner and Outer Planets
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
Compare Inner and Outer Planets
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25. The Flying Objects Moons
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Flying Objects
Moons
Moons are small, natural objects that revolve around other objects.
Some planets have more than one moon, but Earth has only one. Earth’s moon revolves around Earth about every 27 days.
Mercury and Venus do not have any moons.
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26. The Flying Objects Moons
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Flying Objects
Moons
Moons in our solar system differ from each other.
Some moons may contain a lot of ice. Europa, one of Jupiter’s moons, may have a liquid ocean under a layer of ice.
Some moons have many volcanoes. Io, another one of Jupiter’s moons, has the most active volcanoes in the solar system.
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27. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
Dwarf Planets
Pluto was once classified as a planet. Now, it is classified as a dwarf planet.
Dwarf planets are nearly round bodies whose orbits cross the orbits of other bodies.
Most dwarf planets are found in the Kuiper belt, a region of the solar system, and are very far away and hard to study.
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28. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Flying Objects
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29. Meteoroids, Meteors, and Meteorites
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
Meteoroids, Meteors, and Meteorites
Meteoroids are pieces of rock that break off of asteroids and travel through space.
Meteor is a term used to describe the streak of light caused when a meteoroid burns up in Earth’s atmosphere.
If a meteoroid reaches Earth’s surface, it is called a meteorite.
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30. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Flying Objects
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31. Asteroids Asteroids are rock and iron objects that orbit the sun.
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
Asteroids
Asteroids are rock and iron objects that orbit the sun.
Millions of asteroids are found in the wide region between Mars and Jupiter known as the asteroid belt.
Asteroids range in size from as small as a city block to the size of an ocean.
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32. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
Comets
A chunk of frozen gases, rock, ice, and dust is known as a comet.
As comets pass close to the sun, part of the frozen surface breaks away and turns into gases and dust.
These particles reflect the sun’s light and look like long tails that always point away from the sun.
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33. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Flying Objects
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34. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
The Flying Objects
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35. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
Space Watch
Objects such as comets, meteoroids, and asteroids can hit the surface of other bodies in the solar system.
The impact, or hit, from space objects creates impact craters.
Scientists keep track of the size, position, and motion of space objects near Earth using telescopes.
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36. Space Watch A comet named Shoemaker-Levy 9 impacted Jupiter in 1994.
Unit 12 Lesson 1 What Objects Are Part of the Solar System?
Space Watch
A comet named Shoemaker-Levy 9 impacted Jupiter in 1994.
The comet caused bubbles of hot gas to rise into Jupiter’s atmosphere and dark spots to form on its surface.
Scientists also believe a huge object impacted Earth 65 million years ago, leading to changes in the environment that killed all the dinosaurs.
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37. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
Space Watch
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38. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
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39. Unit 12 Lesson 1 What Objects Are Part of the Solar System?
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