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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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Can gravitational lensing from intervening galaxies cause the observed ripples in the Cosmic Microwave Background? (Advanced)
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If I were hypothetically wearing a spacesuit and sitting on one of the Voyager space probes at their current positions in space, how much light would I have? (Intermediate)
What makes certain lunar eclipses so special? (Beginner)
Why is Earth's core molten? (Intermediate)
What will happen to Earth's tides as the moon moves away from us? (Intermediate)
How can spiral galaxies keep their shape? (Advanced)
Does a black hole have a "surface"? (Intermediate)
How can you link telescopes to make a bigger "effective telescope"? (Intermediate)
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)
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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)
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)
At what speed does the Earth move around the Sun? (Beginner)
Why do the planets orbit the sun? (Beginner)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
Why can't a plane fly slowly and let the Earth pass underneath? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
What color is each planet? (Intermediate)
How far is each planet from Earth? (Intermediate)
Why are the Moon and Sun sometimes orange or red? (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)
At what speed does the Earth move around the Sun? (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)
Why do the planets orbit the sun? (Beginner)
What would happen if an asteroid 10 kilometers across hit the Earth? (Beginner)
What color is each planet? (Intermediate)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
How far is each planet from Earth? (Intermediate)
If gravity isn't a force, how does it accelerate objects? (Advanced)
Why can't a plane fly slowly and let the Earth pass underneath? (Beginner)
What would happen if an asteroid 10 kilometers across hit the Earth? (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)
At what speed does the Earth move around the Sun? (Beginner)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (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)
When was the last time all of the planets were aligned? (Beginner)
How long does it take for the Sun's light to reach us? (Beginner)
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