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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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Why do planets rotate? (Intermediate)
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What what a black hole merger look like from a telescope? (Advanced)
Do galaxy mergers have a major impact on star formation rates within the galaxies? (Intermediate)
Our universe is still expanding, does that mean things in our daily life are expanding? (Intermediate)
What was the bright, smoothly moving star that I saw? (Beginner)
What happened to the Arecibo Telescope? (Beginner)
Can I buy or name a star? (Beginner)
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)
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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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How does the position of Moonrise and Moonset change? (Intermediate)
What is that ring (or rainbow) around the moon? (Beginner)
How does the location of sunrise and sunset change throughout the year? (Advanced)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
When was the last time all of the planets were aligned? (Beginner)
Why is the moon in a different place every night? (Beginner)
Can artificial gravity be created in space? (Intermediate)
How do you measure the distance between Earth and the Sun? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
How does the location of sunrise and sunset change throughout the year? (Advanced)
How does the position of Moonrise and Moonset change? (Intermediate)
Why do the planets orbit the sun? (Beginner)
Can artificial gravity be created in space? (Intermediate)
If gravity isn't a force, how does it accelerate objects? (Advanced)
If gravity isn't a force, how does it accelerate objects? (Advanced)
How do you measure the distance between Earth and the Sun? (Intermediate)
Why do the planets orbit the sun? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
Can artificial gravity be created in space? (Intermediate)
How does the position of Moonrise and Moonset change? (Intermediate)
Which planet is most similar to Earth? (Intermediate)
How do we know the Milky Way is a spiral galaxy? (Intermediate)
Are there telescopes that can see the flag and lunar rover on the Moon? (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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