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Can "tired light theory" explain the observed redshifts of galaxies?
(Intermediate)
Can gravitational lensing from intervening galaxies cause the observed ripples in the Cosmic Microwave Background?
(Advanced)
Can I calculate the size of the Universe by converting light years to kilometres?
(Intermediate)
Can the acceleration of the Universe be analogous to apparent acceleration in a airplane?
(Intermediate)
Can two galaxies move away from each other faster than the speed of light?
(Intermediate)
Can we find the place where the Big Bang happened?
(Intermediate)
Can we look back far enough in time to see the Big Bang?
(Beginner)
Can you use an infinite line of reflectors to send light to the edge of the Universe?
(Intermediate)
Cosmologists say the expansion of the universe is accelerating, what is driving this?
(Intermediate)
Could a different theory of gravity explain the dark matter mystery?
(Intermediate)
Could dark energy come from matter anti-matter pairs forming spontaneously and then annihilating?
(Advanced)
Could matter-anti-matter repulsion power the expansion of the universe?
(Intermediate)
Could neutrinos be dark matter?
(Intermediate)
Could our position in the universe affect our perceptions of the expansion?
(Intermediate)
Could the Universe have expanded faster than the speed of light at the Big Bang?
(Intermediate)
Could there have been multiple Big Bangs at different places in the universe?
(Intermediate)
Did the speed of light change over the history of the universe?
(Intermediate)
Did time go slower just after the Big Bang?
(Advanced)
Do galaxies that are receding from us faster than the speed of light disappear from our observations?
(Intermediate)
Does inflation allow for an infinite number of universes?
(Advanced)
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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)
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What is the universe expanding into? (Intermediate)
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How does the position of Moonrise and Moonset change? (Intermediate)
How are light and heavy elements formed? (Advanced)
Why is the moon in a different place every night? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
Why do we not have eclipses every month? (Beginner)
Why do the planets orbit the sun? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
What is the evidence supporting the nebula theory of Solar System formation? (Intermediate)
How can the Universe expand faster than the speed of light during inflation? (Advanced)
How do you measure the distance between Earth and the Sun? (Intermediate)
How does the position of Moonrise and Moonset change? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
Why is the moon in a different place every night? (Beginner)
Why do the planets orbit the sun? (Beginner)
But seriously: what was there before the Big Bang? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
How are light and heavy elements formed? (Advanced)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
What is the universe expanding into? (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 does the position of Moonrise and Moonset change? (Intermediate)
Why do the planets orbit the sun? (Beginner)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
But seriously: what was there before the Big Bang? (Beginner)
What is the universe expanding into? (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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