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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 are photons created and destroyed? (Advanced)
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What what a black hole merger look like from a telescope? (Advanced)
Do galaxy mergers have a major impact on star formation rates within the galaxies? (Intermediate)
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)
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 are light and heavy elements formed? (Advanced)
How do you measure the distance between Earth and the Sun? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
What kind of eyepieces do I need to look at planets? (Intermediate)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
Why do the planets orbit the sun? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
What color is each planet? (Intermediate)
Can artificial gravity be created in space? (Intermediate)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
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)
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)
What color is each planet? (Intermediate)
Can artificial gravity be created in space? (Intermediate)
How does the location of sunrise and sunset change throughout the year? (Advanced)
What is the difference between a "star" and a "sun"? (Beginner)
What kind of eyepieces do I need to look at planets? (Intermediate)
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)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
What color is each planet? (Intermediate)
Why do the planets orbit the sun? (Beginner)
Can artificial gravity be created in space? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
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)
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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