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How does a star take mass from another star?
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Is there any limitation to what a black hole can "suck" in?
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What are quasars made of?
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What happened to all the black holes that were around in the early universe?
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Where is the nearest black hole?
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Did a giant impact cause the Dark Ages? (Beginner)
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How do we know what we observe is x light years away? (Beginner)
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What what a black hole merger look like from a telescope? (Advanced)
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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)
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What is the universe expanding into? (Intermediate)
What do I need to do to become an astronomer? (Beginner)
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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 are light and heavy elements formed? (Advanced)
What is the difference between a "star" and a "sun"? (Beginner)
How can a star burn with no oxygen? (Beginner)
How does the location of sunrise and sunset change throughout the year? (Advanced)
Why do the planets orbit the sun? (Beginner)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
If gravity isn't a force, how does it accelerate objects? (Advanced)
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)
What is the difference between a "star" and a "sun"? (Beginner)
How are light and heavy elements formed? (Advanced)
Why do the planets orbit the 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)
How does the location of sunrise and sunset change throughout the year? (Advanced)
At what speed does the Earth move around the Sun? (Beginner)
How does the position of Moonrise and Moonset change? (Intermediate)
Which planet is most similar to Earth? (Intermediate)
If gravity isn't a force, how does it accelerate objects? (Advanced)
What is the difference between a "star" and a "sun"? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
Why do the planets orbit the sun? (Beginner)
How are light and heavy elements formed? (Advanced)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
How does the position of Moonrise and Moonset change? (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)
Which planet is most similar to Earth? (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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