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Are there any 'lonely galaxies'?
(Beginner)
Has anyone made a map of the Milky Way?
(Beginner)
How can we see the Milky Way if we are inside it?
(Intermediate)
How can we tell what the interiors of planets are like?
(Advanced)
How do we know that superclusters are the largest structures in the universe?
(Advanced)
Is the Local Group expanding along with the entire Universe?
(Intermediate)
What do "homogeneity" and "isotropy" mean?
(Intermediate)
What is the largest structure in the universe?
(Intermediate)
What is the origin of spiral structure in galaxies?
(Intermediate)
Where, in relation to the entire universe, is the Milky Way located?
(Intermediate)
Why do we assume that the universe is homogeneous?
(Intermediate)
Why doesn't the ammonia and methane in Jupiter's atmosphere sink into the core?
(Advanced)
Would a planet near the galactic center have a brighter night sky?
(Intermediate)
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Is Andromeda part of the Milky Way? Where can I find them in the sky? (Beginner)
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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)
Are aliens or UFOs real? (Beginner)
How are light and heavy elements formed? (Advanced)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
Does the Sun orbit the Earth as well as the Earth orbiting the Sun? (Beginner)
How is it proved that the Universe is expanding? (Intermediate)
What is the evidence supporting the nebula theory of Solar System formation? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
When was the last time all of the planets were aligned? (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)
How are light and heavy elements formed? (Advanced)
How far is each planet from Earth? (Intermediate)
Are aliens or UFOs real? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
How does the location of sunrise and sunset change throughout the year? (Advanced)
Why do the planets orbit the sun? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
When was the last time all of the planets were aligned? (Beginner)
What color is each planet? (Intermediate)
How are light and heavy elements formed? (Advanced)
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)
What is the difference between a "star" and a "sun"? (Beginner)
How is it proved that the Universe is expanding? (Intermediate)
How does the location of sunrise and sunset change throughout the year? (Advanced)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
When was the last time all of the planets were aligned? (Beginner)
Can artificial gravity be created in space? (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)
How long does it take for the Sun's light to reach us? (Beginner)
When was the last time all of the planets were aligned? (Beginner)
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