Review and reinforcement worksheet on the outer planets, featuring questions about planetary characteristics and astronomy concepts.
A worksheet titled "The Outer Planets" with questions about the five outer planets, gas giants, Pluto, and Saturn's rings.
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Step-by-step solution for: Solved Date Class SECTION 2-4 REVIEW AND REINF The Outer | Chegg.com
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Show Answer Key & Explanations
Step-by-step solution for: Solved Date Class SECTION 2-4 REVIEW AND REINF The Outer | Chegg.com
Let’s go through each question one by one. I’ll explain the answers clearly so you can understand and write them down for your homework.
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1. What are the five outer planets?
The outer planets are the ones farthest from the Sun, beyond the asteroid belt. They are:
- Jupiter
- Saturn
- Uranus
- Neptune
- Pluto (Note: Pluto is now called a “dwarf planet,” but in many older textbooks or sections like this, it’s still included as an outer planet.)
✔ So the five outer planets are: Jupiter, Saturn, Uranus, Neptune, and Pluto.
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2. Which planets are the gas giants?
Gas giants are huge planets made mostly of gases like hydrogen and helium — not solid rock like Earth.
The gas giants are:
- Jupiter
- Saturn
- Uranus
- Neptune
(Pluto is NOT a gas giant — it’s small and icy/rocky.)
✔ Answer: Jupiter, Saturn, Uranus, and Neptune
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3. What are the two main differences between Pluto and the gas giants?
Let’s compare:
→ Size: Gas giants are HUGE. Pluto is tiny — smaller than Earth’s moon!
→ Composition: Gas giants are made of gas (hydrogen, helium). Pluto is made of ice and rock.
✔ Two main differences:
1. Size: Gas giants are much larger than Pluto.
2. Composition: Gas giants are made of gas; Pluto is made of ice and rock.
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4. Why doesn’t the gas on a gas giant escape into space, as it has on Mercury?
Mercury is small and has weak gravity — so its atmosphere escaped long ago.
Gas giants are MASSIVE. Their gravity is super strong — so strong that even light gases like hydrogen can’t escape.
✔ Answer: Because gas giants have very strong gravity that holds onto their gases.
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5. What object in the solar system has a composition similar to that of the gas giants?
The Sun! It’s also made mostly of hydrogen and helium — just like the gas giants.
✔ Answer: The Sun
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6. What planet is by far the most massive of all the planets that revolve around the sun?
Jupiter is the biggest and heaviest planet. It’s more than twice as massive as ALL the other planets combined!
✔ Answer: Jupiter
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7. What are Saturn’s rings made of?
Saturn’s rings aren’t solid — they’re made of billions of tiny pieces of ice and rock, ranging from dust-sized to house-sized.
✔ Answer: Ice and rock particles
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8. Why did astronomers know where to look to discover Neptune?
They noticed Uranus wasn’t moving exactly how it should based on gravity calculations. Something else must be pulling on it — so they predicted where another planet (Neptune) must be… and looked there!
✔ Answer: Because irregularities in Uranus’s orbit suggested another planet was nearby, so they calculated where it should be.
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9. Why do astronomers sometimes consider Pluto and its moon, Charon, to be a double planet?
Charon is almost half the size of Pluto — which is unusual. Most moons are much smaller than their planets. Also, they orbit around a point *between* them, not around Pluto’s center. That makes them act like a pair.
✔ Answer: Because Charon is very large compared to Pluto, and they orbit a common center point between them — making them seem like a twin system.
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10. Define gas giant.
A gas giant is a giant planet made mostly of gases like hydrogen and helium, with no solid surface. They’re much bigger than rocky planets like Earth.
✔ Definition: A gas giant is a large planet composed mainly of hydrogen and helium, with no solid surface.
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Final Answer:
1. Jupiter, Saturn, Uranus, Neptune, Pluto
2. Jupiter, Saturn, Uranus, Neptune
3. 1) Gas giants are much larger; 2) Gas giants are made of gas, Pluto is made of ice and rock
4. Because gas giants have very strong gravity that holds onto their gases
5. The Sun
6. Jupiter
7. Ice and rock particles
8. Because irregularities in Uranus’s orbit suggested another planet was nearby, so they calculated where it should be
9. Because Charon is very large compared to Pluto, and they orbit a common center point between them
10. A gas giant is a large planet composed mainly of hydrogen and helium, with no solid surface
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1. What are the five outer planets?
The outer planets are the ones farthest from the Sun, beyond the asteroid belt. They are:
- Jupiter
- Saturn
- Uranus
- Neptune
- Pluto (Note: Pluto is now called a “dwarf planet,” but in many older textbooks or sections like this, it’s still included as an outer planet.)
✔ So the five outer planets are: Jupiter, Saturn, Uranus, Neptune, and Pluto.
---
2. Which planets are the gas giants?
Gas giants are huge planets made mostly of gases like hydrogen and helium — not solid rock like Earth.
The gas giants are:
- Jupiter
- Saturn
- Uranus
- Neptune
(Pluto is NOT a gas giant — it’s small and icy/rocky.)
✔ Answer: Jupiter, Saturn, Uranus, and Neptune
---
3. What are the two main differences between Pluto and the gas giants?
Let’s compare:
→ Size: Gas giants are HUGE. Pluto is tiny — smaller than Earth’s moon!
→ Composition: Gas giants are made of gas (hydrogen, helium). Pluto is made of ice and rock.
✔ Two main differences:
1. Size: Gas giants are much larger than Pluto.
2. Composition: Gas giants are made of gas; Pluto is made of ice and rock.
---
4. Why doesn’t the gas on a gas giant escape into space, as it has on Mercury?
Mercury is small and has weak gravity — so its atmosphere escaped long ago.
Gas giants are MASSIVE. Their gravity is super strong — so strong that even light gases like hydrogen can’t escape.
✔ Answer: Because gas giants have very strong gravity that holds onto their gases.
---
5. What object in the solar system has a composition similar to that of the gas giants?
The Sun! It’s also made mostly of hydrogen and helium — just like the gas giants.
✔ Answer: The Sun
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6. What planet is by far the most massive of all the planets that revolve around the sun?
Jupiter is the biggest and heaviest planet. It’s more than twice as massive as ALL the other planets combined!
✔ Answer: Jupiter
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7. What are Saturn’s rings made of?
Saturn’s rings aren’t solid — they’re made of billions of tiny pieces of ice and rock, ranging from dust-sized to house-sized.
✔ Answer: Ice and rock particles
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8. Why did astronomers know where to look to discover Neptune?
They noticed Uranus wasn’t moving exactly how it should based on gravity calculations. Something else must be pulling on it — so they predicted where another planet (Neptune) must be… and looked there!
✔ Answer: Because irregularities in Uranus’s orbit suggested another planet was nearby, so they calculated where it should be.
---
9. Why do astronomers sometimes consider Pluto and its moon, Charon, to be a double planet?
Charon is almost half the size of Pluto — which is unusual. Most moons are much smaller than their planets. Also, they orbit around a point *between* them, not around Pluto’s center. That makes them act like a pair.
✔ Answer: Because Charon is very large compared to Pluto, and they orbit a common center point between them — making them seem like a twin system.
---
10. Define gas giant.
A gas giant is a giant planet made mostly of gases like hydrogen and helium, with no solid surface. They’re much bigger than rocky planets like Earth.
✔ Definition: A gas giant is a large planet composed mainly of hydrogen and helium, with no solid surface.
---
Final Answer:
1. Jupiter, Saturn, Uranus, Neptune, Pluto
2. Jupiter, Saturn, Uranus, Neptune
3. 1) Gas giants are much larger; 2) Gas giants are made of gas, Pluto is made of ice and rock
4. Because gas giants have very strong gravity that holds onto their gases
5. The Sun
6. Jupiter
7. Ice and rock particles
8. Because irregularities in Uranus’s orbit suggested another planet was nearby, so they calculated where it should be
9. Because Charon is very large compared to Pluto, and they orbit a common center point between them
10. A gas giant is a large planet composed mainly of hydrogen and helium, with no solid surface
Parent Tip: Review the logic above to help your child master the concept of outer planet worksheet.
