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But seriously: what was there before the Big Bang?
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Can you see the future as you fall into a black hole?
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How can the Universe expand faster than the speed of light during inflation?
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How do gravitons escape black holes to tell the universe about their gravity?
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If gravity is a "curvature of space" rather than a force, why do a ball and bullet follow different paths?
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If gravity isn't a force, how does it accelerate objects?
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If light has no mass, then what draws it into a black hole?
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If spacetime is curved, is it possible for us to look into space and see light from Earth from long ago?
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Is there any possibility that the Solar System or the Universe is in a black hole?
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What are "curled" dimensions?
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What happens to spacetime inside a black hole?
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Why isn't the sky bright at night if the universe has so many stars? (Intermediate)
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Is speed of light the same everywhere ? (Beginner)
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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 long could life on Earth survive if the Sun stopped shining? (Beginner)
Do we see the same stars from above and below the equator? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
How does the position of Moonrise and Moonset change? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
Why do the planets orbit the sun? (Beginner)
Why is the moon in a different place every night? (Beginner)
Why are there high tides during a Full Moon? (Intermediate)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
Can artificial gravity be created in space? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
How does the position of Moonrise and Moonset change? (Intermediate)
How do you measure the distance between Earth and the Sun? (Intermediate)
Why do the planets orbit the sun? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
Why are there high tides during a Full Moon? (Intermediate)
Why is the moon in a different place every night? (Beginner)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
Can artificial gravity be created in space? (Intermediate)
How do you measure the distance between Earth and the Sun? (Intermediate)
Why do the planets orbit the sun? (Beginner)
How does the position of Moonrise and Moonset change? (Intermediate)
Why is the moon in a different place every night? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
But seriously: what was there before the Big Bang? (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)
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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