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Is light blueshifted when it is gravitationally lensed?
(Intermediate)
What would the Big Crunch look like to an observer on Earth?
(Advanced)
Why are there blue shifted galaxies?
(Intermediate)
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What are black holes made of? (Intermediate)
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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)
How can spiral galaxies keep their shape? (Advanced)
Does a black hole have a "surface"? (Intermediate)
How can you link telescopes to make a bigger "effective telescope"? (Intermediate)
What should I know about the upcoming Solar Eclipse (2017)? (Beginner)
Do galaxies that are receding from us faster than the speed of light disappear from our observations? (Intermediate)
Why are astronomers interested in gravitational waves? (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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Why are there both high and low tides? (Intermediate)
What are the names of the earth, moon, sun, and solar system? (Beginner)
What's going to happen on December 21st 2012? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
What color is each planet? (Intermediate)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
Is the distance from the Earth to the Sun changing? (Advanced)
What is the difference between a "star" and a "sun"? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
Why is twilight short near the equator? (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)
At what speed does the Earth move around the Sun? (Beginner)
Why do the planets orbit the sun? (Beginner)
How far is each planet from Earth? (Intermediate)
Why are the Moon and Sun sometimes orange or red? (Beginner)
Why do stars twinkle? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
What are the requirements for being a planet? (Beginner)
Is the distance from the Earth to the Sun changing? (Advanced)
What color is each planet? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
How far is each planet from Earth? (Intermediate)
Why do the planets orbit 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)
What would happen if an asteroid 10 kilometers across hit the Earth? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
Why do stars twinkle? (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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Physics
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The History of Astronomy
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