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When was the last time all of the planets were aligned? (Beginner)
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How far is each planet from Earth? (Intermediate)
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At what speed does the Earth move around the Sun? (Beginner)
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When was the last time all of the planets were aligned? (Beginner)
What color is each planet? (Intermediate)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
How far is each planet from Earth? (Intermediate)
How do you measure the distance between Earth and the Sun? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
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When was the last time all of the planets were aligned? (Beginner)
What color is each planet? (Intermediate)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
How far is each planet from Earth? (Intermediate)
How do you measure the distance between Earth and the Sun? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
Why do the planets orbit the sun? (Beginner)
Why do airplanes take longer to fly West than East? (Intermediate)
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At what speed does the Earth move around the Sun? (Beginner)
How far is each planet from Earth? (Intermediate)
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How do you measure the distance between Earth and the Sun? (Intermediate)
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