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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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How can we compare dark matter and dark energy? (Intermediate)
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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)
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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)
Which planet is most similar to Earth? (Intermediate)
How do you measure the distance between Earth and the Sun? (Intermediate)
Why do the planets orbit the sun? (Beginner)
What is that ring (or rainbow) around the moon? (Beginner)
Why do the size and brightness of the full moon change? (Intermediate)
Why is the moon in a different place every night? (Beginner)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
Which planet is most similar to Earth? (Intermediate)
Why do the planets orbit the sun? (Beginner)
How are light and heavy elements formed? (Advanced)
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 color is each planet? (Intermediate)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
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 are light and heavy elements formed? (Advanced)
Why do the planets orbit the sun? (Beginner)
Which planet is most similar to Earth? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
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 color is each planet? (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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