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Can we harvest H & O from space to make water?
(Intermediate)
Does the Sun have any heavy elements?
(Beginner)
How can a star burn with no oxygen?
(Beginner)
Is it true that the Sun burns off a billion tons of gas every 5 seconds?
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What elements make up the Sun?
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What happens to the helium formed in the Sun?
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What is a nova?
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What is the evidence supporting the nebula theory of Solar System formation?
(Intermediate)
What is the origin of the stellar classification system "OBAFGKM"?
(Intermediate)
What is the physical difference between a star and a planet?
(Intermediate)
Where are stars born?
(Beginner)
Where did all the water in the universe come from?
(Intermediate)
Why doesn't the hydrogen on Jupiter explode?
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Why is the Cosmic Microwave Background not absorbed by interstellar hydrogen?
(Advanced)
Why will fusion wait until hydrogen is gone before starting to fuse heavier atoms?
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What should I know about the upcoming Solar Eclipse? (2017)
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Why do we not have eclipses every month? (Beginner)
Are there eclipses on other planets? (Intermediate)
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Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
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How do you measure the distance between Earth and the Sun? (Intermediate)
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What color is each planet? (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)
Why are the Moon and Sun sometimes orange or red? (Beginner)
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)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
Why do airplanes take longer to fly West than East? (Intermediate)
How far is each planet from Earth? (Intermediate)
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What color is each planet? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
How far is each planet from Earth? (Intermediate)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
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