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What are "blue stragglers" in globular clusters?
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What would happen if two stars collided?
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Are black holes spherical? (Intermediate)
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Is speed of light the same everywhere ? (Beginner)
How does Venus have sulphuric acid in it's clouds? (Beginner)
Earth's Bow Shock (Advanced)
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)
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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)
How do you measure the distance between Earth and the Sun? (Intermediate)
Why is the moon in a different place every night? (Beginner)
Why do the planets orbit the sun? (Beginner)
How can we see the Milky Way if we are inside it? (Intermediate)
Is the speed of light constant? (Beginner)
What are the names of the earth, moon, sun, and solar system? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
Which planet is most similar to Earth? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
Which planet is most similar to Earth? (Intermediate)
How far is each planet from Earth? (Intermediate)
What was the bright, smoothly moving star that I saw? (Beginner)
Why do the planets orbit the sun? (Beginner)
Why is the moon in a different place every night? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
How can the Universe expand faster than the speed of light during inflation? (Advanced)
How can we see the Milky Way if we are inside it? (Intermediate)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
How far is each planet from Earth? (Intermediate)
Why is the moon in a different place every night? (Beginner)
How does the position of Moonrise and Moonset change? (Intermediate)
Which planet is most similar to Earth? (Intermediate)
Why do the planets orbit the sun? (Beginner)
What was the bright, smoothly moving star that I saw? (Beginner)
Why do we not have eclipses every month? (Beginner)
At what speed does the Earth move around the Sun? (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)
How do you measure the distance between Earth and the Sun? (Intermediate)
Is the Moon moving away from the Earth? When was this discovered? (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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