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Can we harvest H & O from space to make water?
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How can a star burn with no oxygen?
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Is the reddish dust of Mars biogenic?
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Is there oxygen in the atmospheres of other planets?
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What would happen if you took off your helmet in space?
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Where did all the water in the universe come from?
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Why doesn't the hydrogen on Jupiter explode?
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How are black holes made? Could one be made close to us? (Beginner)
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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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Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
What color is each planet? (Intermediate)
Why are the Moon and Sun sometimes orange or red? (Beginner)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
How far is each planet from Earth? (Intermediate)
Why do airplanes take longer to fly West than East? (Intermediate)
Is the distance from the Earth to the Sun changing? (Advanced)
How do you measure the distance between Earth and the Sun? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
When was the last time all of the planets were aligned? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
What color is each planet? (Intermediate)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
How far is each planet from Earth? (Intermediate)
How does the position of Moonrise and Moonset change? (Intermediate)
When was the last time all of the planets were aligned? (Beginner)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
Is the distance from the Earth to the Sun changing? (Advanced)
Why do airplanes take longer to fly West than East? (Intermediate)
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)
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)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
When was the last time all of the planets were aligned? (Beginner)
Why do airplanes take longer to fly West than East? (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)
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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