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Do unmanned spacecraft like Voyager travel in straight lines?
(Intermediate)
When unmanned spacecraft accelerate in space, what causes them to slow down?
(Intermediate)
Why did the Pioneer and Voyager take only 2 years to reach Jupiter, while Galileo and Cassini took more than 5 years?
(Intermediate)
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Did the Sumerians measure precession? (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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What color is each planet? (Intermediate)
Why do the planets orbit the sun? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
Why are the Moon and Sun sometimes orange or red? (Beginner)
How does the position of Moonrise and Moonset change? (Intermediate)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
What are the requirements for being a planet? (Beginner)
How far is each planet from Earth? (Intermediate)
Why are there high tides during a Full Moon? (Intermediate)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
What color is each planet? (Intermediate)
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)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
What would happen if an asteroid 10 kilometers across hit the Earth? (Beginner)
What are the requirements for being a planet? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
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)
Why do the planets orbit the sun? (Beginner)
Is the distance from the Earth to the Sun changing? (Advanced)
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)
What are the names of the earth, moon, sun, and solar system? (Beginner)
What are the requirements for being a planet? (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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