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Can you use an infinite line of reflectors to send light to the edge of the Universe?
(Intermediate)
Could someone travel the universe in his or her own lifetime?
(Beginner)
How are photons created and destroyed?
(Advanced)
How do photons from distant objects maintain enough energy to reach us?
(Intermediate)
How do planets capture satellites?
(Advanced)
How do you calculate the lifetime of the Sun?
(Advanced)
How long do supernova remnants last?
(Intermediate)
How much power is contained in a beam of light?
(Intermediate)
How powerful are quasars?
(Intermediate)
Is cosmic expansion happening on microscopic scales?
(Advanced)
Is light of different colors affected differently by gravity?
(Intermediate)
What causes a particle to decay?
(Intermediate)
What is the photoelectric effect? Why can't multiple low-frequency photons free an electron?
(Intermediate)
What type of energy does a black hole have?
(Intermediate)
When the Sun converts mass to energy, do the orbits of the planets change?
(Advanced)
Where did the matter in the universe come from?
(Intermediate)
Where did the Universe come from?
(Intermediate)
Where does the kinetic energy of infalling bodies come from?
(Intermediate)
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How dangerous are the asteroids? (Intermediate)
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Is speed of light the same everywhere ? (Beginner)
How does Venus have sulphuric acid in it's clouds? (Beginner)
Earth's Bow Shock (Advanced)
How much does the Earth "wobble" on its orbit due to the Moon's gravity? (Intermediate)
Why is the sun red? During sunset, Northeastern US, Summer 2021 (Beginner)
Why do rays from Sun appear to converge at a point? (Beginner)
But seriously: what was there before the Big Bang? (Beginner)
How far can photons move freely in the early universe (Advanced)
How likely is it that the Solar System has had or will have a close encounter with another star? (Intermediate)
How do we know what we observe is x light years away? (Beginner)
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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 far is each planet from Earth? (Intermediate)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
Which planet is most similar to Earth? (Intermediate)
How does the position of Moonrise and Moonset change? (Intermediate)
How do you measure the distance between Earth and the Sun? (Intermediate)
What would happen if the Moon fell out of its orbit around Earth? (Intermediate)
Why is the moon in a different place every night? (Beginner)
Earth's Bow Shock (Advanced)
How does night and day work? (Beginner)
Is it possible for amateurs to do optical interferometry? (Intermediate)
What was the bright, smoothly moving star that I saw? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
How far is each planet from Earth? (Intermediate)
What kind of eyepieces do I need to look at planets? (Intermediate)
How do you measure the distance between Earth and the Sun? (Intermediate)
What would happen if the Moon fell out of its orbit around Earth? (Intermediate)
Which planet is most similar to Earth? (Intermediate)
Earth's Bow Shock (Advanced)
At what speed does the Earth move around the Sun? (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)
How are light and heavy elements formed? (Advanced)
How far is each planet from Earth? (Intermediate)
How do you measure the distance between Earth and the Sun? (Intermediate)
Which planet is most similar to Earth? (Intermediate)
What was the bright, smoothly moving star that I saw? (Beginner)
Why is the moon in a different place every night? (Beginner)
What would happen if the Moon fell out of its orbit around Earth? (Intermediate)
Earth's Bow Shock (Advanced)
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)
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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