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What causes gamma ray bursts?
(Intermediate)
What happens to a substance if its speed is more than the speed of light?
(Intermediate)
What happens to the material that has been sucked into a black hole?
(Intermediate)
What happens when you change the mass of a White Dwarf or Neutron Star?
(Intermediate)
What is a Cepheid variable?
(Intermediate)
What is a white hole?
(Advanced)
What is the density of a black hole?
(Advanced)
What is the life cycle of a star?
(Intermediate)
What is the mass of the Universe?
(Intermediate)
What is the physical difference between a star and a planet?
(Intermediate)
What kind of instruments are used to detect extrasolar planets?
(Intermediate)
What makes a satellite geosyncronise itself with Earth's orbit?
(Intermediate)
What would happen if the gravity on Earth was suddenly turned off?
(Beginner)
When the Sun converts mass to energy, do the orbits of the planets change?
(Advanced)
Where did the Universe come from?
(Intermediate)
Why are astronomers interested in gravitational waves?
(Intermediate)
Why are stars of different masses?
(Advanced)
Why do the explosions of Type Ia supernovae have a more predictable spectrum than those of regular Type II supernovae?
(Advanced)
Why doesn't gravity change the speed of light?
(Beginner)
Why is Neptune still considered a planet when Pluto crosses its orbit?
(Intermediate)
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What should I know about the upcoming Solar Eclipse (2017)? (Beginner)
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What is the universe expanding into? (Intermediate)
What do I need to do to become an astronomer? (Beginner)
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How are light and heavy elements formed? (Advanced)
What color is each planet? (Intermediate)
Can artificial gravity be created in space? (Intermediate)
Why are the Moon and Sun sometimes orange or red? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
Why do stars twinkle? (Beginner)
Why can't a plane fly slowly and let the Earth pass underneath? (Beginner)
How does the location of sunrise and sunset change throughout the year? (Advanced)
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)
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)
Can artificial gravity be created in space? (Intermediate)
How do you measure the distance between Earth and the Sun? (Intermediate)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
Why do stars twinkle? (Beginner)
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)
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)
How do you measure the distance between Earth and the Sun? (Intermediate)
Can artificial gravity be created in space? (Intermediate)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
How does the location of sunrise and sunset change throughout the year? (Advanced)
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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