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Are aliens or UFOs real?
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Can I listen to the SETI@home radio signal?
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Can life exist on the recently discovered extrasolar planets?
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Can supernovae hinder the formation of life in galaxies?
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Could there be life in the galaxies nearest to the Milky Way?
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Do similar laws of physics throughout the Universe imply that all life must be like life on Earth?
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Have astronomers observed any phenomena that could be produced by extraterrestrial civilizations?
(Intermediate)
Is it worthwhile to continue the search for extraterrestrial life?
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Is there oxygen in the atmospheres of other planets?
(Intermediate)
What do meteorites tell us about life on other planets?
(Intermediate)
What is a Dyson Sphere?
(Intermediate)
Where is everybody?
(Intermediate)
Why does the SETI project search for radio signals?
(Intermediate)
Why search for only Earth-like life on other planets?
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Would extraterrestrial civilizations know that there is life on Earth?
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Wouldn't the vast distances of space distort SETI signals into unintelligeble forms?
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How do we measure distances to other stars? (Beginner)
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What what a black hole merger look like from a telescope? (Advanced)
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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 do you measure the distance between Earth and the Sun? (Intermediate)
How are light and heavy elements formed? (Advanced)
At what speed does the Earth move around the Sun? (Beginner)
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 does the position of Moonrise and Moonset change? (Intermediate)
Why do the planets orbit the sun? (Beginner)
When was the last time all of the planets were aligned? (Beginner)
What would happen if an asteroid 10 kilometers across hit the Earth? (Beginner)
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)
How does the position of Moonrise and Moonset change? (Intermediate)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
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)
What is that ring (or rainbow) around the moon? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
Why do the planets orbit the sun? (Beginner)
Can artificial gravity be created in space? (Intermediate)
How does the location of sunrise and sunset change throughout the year? (Advanced)
If gravity isn't a force, how does it accelerate objects? (Advanced)
How do you measure the distance between Earth and the Sun? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
Why do the planets orbit the sun? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
Can artificial gravity be created in space? (Intermediate)
Which planet is most similar to Earth? (Intermediate)
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'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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