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Is the Sun always up for exactly 12 hours at the equator?
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Why doesn't the length of each day change much around the solstices?
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Can other terrestrial moons be (or have been) stable? (Advanced)
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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 the difference between a "star" and a "sun"? (Beginner)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
Which planet is most similar to Earth? (Intermediate)
How do you measure the distance between Earth and the Sun? (Intermediate)
Why do the planets orbit the sun? (Beginner)
What is that ring (or rainbow) around the moon? (Beginner)
Why do the size and brightness of the full moon change? (Intermediate)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (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)
Which planet is most similar to Earth? (Intermediate)
Why do the planets orbit the sun? (Beginner)
How are light and heavy elements formed? (Advanced)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
How does the position of Moonrise and Moonset change? (Intermediate)
What color is each planet? (Intermediate)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
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)
How are light and heavy elements formed? (Advanced)
Why do the planets orbit the 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 does the position of Moonrise and Moonset change? (Intermediate)
What color is each planet? (Intermediate)
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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