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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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What is the solar cycle? (Beginner)
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What should I know about the upcoming Solar Eclipse (2017)? (Beginner)
Do galaxies that are receding from us faster than the speed of light disappear from our observations? (Intermediate)
Why are astronomers interested in gravitational waves? (Intermediate)
Can two galaxies move away from each other faster than the speed of light? (Intermediate)
What is a graviton? (Intermediate)
Why are there high tides during a Full Moon? (Intermediate)
Why is Neptune still considered a planet when Pluto crosses its orbit? (Intermediate)
Could there be objects orbiting interior to Mercury? (Intermediate)
Have the inner planets cleared their neighborhood? (Intermediate)
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)
Why is looking out into space the same as looking back in time? (Beginner)
Can we find the place where the Big Bang happened? (Intermediate)
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What color is each planet? (Intermediate)
Why do airplanes take longer to fly West than East? (Intermediate)
Why do stars twinkle? (Beginner)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
Why can't a plane fly slowly and let the Earth pass underneath? (Beginner)
How far is each planet from Earth? (Intermediate)
When was the last time all of the planets were aligned? (Beginner)
At what speed does the Earth move around the Sun? (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)
What is the difference between a "star" and a "sun"? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
Why do stars twinkle? (Beginner)
How far is each planet from Earth? (Intermediate)
Why do airplanes take longer to fly West than East? (Intermediate)
Can artificial gravity be created in space? (Intermediate)
Why do the planets orbit the sun? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
What color is each planet? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
How far is each planet from Earth? (Intermediate)
Can artificial gravity be created in space? (Intermediate)
Why do stars twinkle? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
Why do airplanes take longer to fly West than East? (Intermediate)
When was the last time all of the planets were aligned? (Beginner)
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)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
How long does it take for the Sun's light to reach us? (Beginner)
When was the last time all of the planets were aligned? (Beginner)
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