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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 is the universe expanding into? (Intermediate)
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What are constellations used for? (Intermediate)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
When will humans travel to Mars and revisit the Moon? (Intermediate)
How do we know what other planets (and stars, galaxies, etc.) are made of? (Intermediate)
How are planets affected by the Hot Ionised Medium? (Advanced)
What would happen to the Earth if an asteroid hit the Moon? (Intermediate)
Considering the motion of the Earth, the solar system, and the galaxy, how fast am I moving while lying in bed asleep? (Intermediate)
Is there really a 10th planet? (Beginner)
Is time travel possible? (Beginner)
Where does the name "Milky Way" come from? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
When was the last time all of the planets were aligned? (Beginner)
How does the location of sunrise and sunset change throughout the year? (Advanced)
Is speed of light the same everywhere ? (Beginner)
What was the bright, smoothly moving star that I saw? (Beginner)
Why is the sun red? During sunset, Northeastern US, Summer 2021 (Beginner)
Which planet is most similar to Earth? (Intermediate)
What are constellations used for? (Intermediate)
How does Venus have sulphuric acid in it's clouds? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
What was the bright, smoothly moving star that I saw? (Beginner)
How does the position of Moonrise and Moonset change? (Intermediate)
Which planet is most similar to Earth? (Intermediate)
What are constellations used for? (Intermediate)
How does the location of sunrise and sunset change throughout the year? (Advanced)
Why do we not have eclipses every month? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
Why do the planets orbit the sun? (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)
How do you measure the distance between Earth and the Sun? (Intermediate)
Is the Moon moving away from the Earth? When was this discovered? (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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