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How do the astronauts communicate in space if sound cannot travel in a vacuum?
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Can astronauts play musical instruments in space?
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Can I communicate faster than light?
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Can I listen to the SETI@home radio signal?
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How much power is contained in a beam of light?
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What effect did compression waves have immediately following the Big Bang?
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Why do photos of space taken from space never show any stars? (Intermediate)
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How much does the Earth "wobble" on its orbit due to the Moon's gravity? (Intermediate)
Why is the sun red? During sunset, Northeastern US, Summer 2021 (Beginner)
Why do rays from Sun appear to converge at a point? (Beginner)
But seriously: what was there before the Big Bang? (Beginner)
How far can photons move freely in the early universe (Advanced)
How likely is it that the Solar System has had or will have a close encounter with another star? (Intermediate)
How do we know what we observe is x light years away? (Beginner)
What makes quantum mechanics and general relativity incompatible? (Advanced)
What are we doing about Space Junk?
What what a black hole merger look like from a telescope? (Advanced)
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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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Why is the sun red? During sunset, Northeastern US, Summer 2021 (Beginner)
Why do rays from Sun appear to converge at a point? (Beginner)
How do we know what we observe is x light years away? (Beginner)
But seriously: what was there before the Big Bang? (Beginner)
How far can photons move freely in the early universe (Advanced)
How likely is it that the Solar System has had or will have a close encounter with another star? (Intermediate)
What is the universe expanding into? (Intermediate)
What makes quantum mechanics and general relativity incompatible? (Advanced)
How much does the Earth "wobble" on its orbit due to the Moon's gravity? (Intermediate)
What what a black hole merger look like from a telescope? (Advanced)
What is the difference between a "star" and a "sun"? (Beginner)
How does the position of Moonrise and Moonset change? (Intermediate)
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)
At what speed does the Earth move around the Sun? (Beginner)
Why is the sun red? During sunset, Northeastern US, Summer 2021 (Beginner)
What is the universe expanding into? (Intermediate)
But seriously: what was there before the Big Bang? (Beginner)
Why is the moon in a different place every night? (Beginner)
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 does the position of Moonrise and Moonset change? (Intermediate)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
But seriously: what was there before the Big Bang? (Beginner)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
What is the universe expanding into? (Intermediate)
What was the bright, smoothly moving star that I saw? (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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