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Can supernovae hinder the formation of life in galaxies? (Beginner)
Do most astronomers believe in God based on the available scientific evidence? (Beginner)
Why is the moon in a different place every night? (Beginner)
Can artificial gravity be created in space? (Intermediate)
What kind of eyepieces do I need to look at planets? (Intermediate)
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What is the density of a black hole? (Advanced)
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How does the location of sunrise and sunset change throughout the year? (Advanced)
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)
How are light and heavy elements formed? (Advanced)
How does the position of Moonrise and Moonset change? (Intermediate)
Are there telescopes that can see the flag and lunar rover on the Moon? (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 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 position of Moonrise and Moonset change? (Intermediate)
How does the location of sunrise and sunset change throughout the year? (Advanced)
At what speed does the Earth move around the Sun? (Beginner)
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)
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How long does it take for the Sun's light to reach us? (Beginner)
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