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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?
(Beginner)
What elements make up the Sun?
(Beginner)
What happens to the helium formed in the Sun?
(Beginner)
What is a nova?
(Beginner)
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?
(Intermediate)
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?
(Advanced)
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Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
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Do galaxies that are receding from us faster than the speed of light disappear from our observations? (Intermediate)
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Why are there high tides during a Full Moon? (Intermediate)
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What caused the Big Bang and created the Universe? (Beginner)
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What is the universe expanding into? (Intermediate)
What do I need to do to become an astronomer? (Beginner)
What's the difference between astronomy and astrology? (Beginner)
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What color is each planet? (Intermediate)
When was the last time all of the planets were aligned? (Beginner)
How are light and heavy elements formed? (Advanced)
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)
What is the evidence supporting the nebula theory of Solar System formation? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
How does the location of sunrise and sunset change throughout the year? (Advanced)
What is the difference between a "star" and a "sun"? (Beginner)
What color is each planet? (Intermediate)
When was the last time all of the planets were aligned? (Beginner)
How are light and heavy elements formed? (Advanced)
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 does the location of sunrise and sunset change throughout the year? (Advanced)
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)
What is the evidence supporting the nebula theory of Solar System formation? (Intermediate)
How are light and heavy elements formed? (Advanced)
What color is each planet? (Intermediate)
How far is each planet from Earth? (Intermediate)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
When was the last time all of the planets were aligned? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
How does the location of sunrise and sunset change throughout the year? (Advanced)
What is the difference between a "star" and a "sun"? (Beginner)
What is the evidence supporting the nebula theory of Solar System formation? (Intermediate)
What's going to happen on December 21st 2012? (Intermediate)
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)
How do you measure the distance between Earth and the Sun? (Intermediate)
Why do the planets orbit the sun? (Beginner)
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What is the universe expanding into? (Intermediate)
When will Halley's Comet return? (Intermediate)
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