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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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What percent of the time can astronomers observe without interference from the Moon? (Beginner)
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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)
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)
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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 are light and heavy elements formed? (Advanced)
What is the difference between a "star" and a "sun"? (Beginner)
How does the location of sunrise and sunset change throughout the year? (Advanced)
How can a star burn with no oxygen? (Beginner)
Why do the planets orbit the 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)
If gravity isn't a force, how does it accelerate objects? (Advanced)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
How are light and heavy elements formed? (Advanced)
Why do the planets orbit the 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)
How does the location of sunrise and sunset change throughout the year? (Advanced)
How does the position of Moonrise and Moonset change? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
Which planet is most similar to Earth? (Intermediate)
If gravity isn't a force, how does it accelerate objects? (Advanced)
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 are light and heavy elements formed? (Advanced)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
How does the position of Moonrise and Moonset change? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
How does the location of sunrise and sunset change throughout the year? (Advanced)
Which planet is most similar to Earth? (Intermediate)
Are there telescopes that can see the flag and lunar rover on the Moon? (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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