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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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Can I calculate the size of the Universe by converting light years to kilometres? (Intermediate)
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What is the universe expanding into? (Intermediate)
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What color is each planet? (Intermediate)
How far is each planet from Earth? (Intermediate)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
Why do the planets orbit the sun? (Beginner)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
Why can't a plane fly slowly and let the Earth pass underneath? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
What color is each planet? (Intermediate)
How far is each planet from Earth? (Intermediate)
Why are the Moon and Sun sometimes orange or red? (Beginner)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
Why can't a plane fly slowly and let the Earth pass underneath? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
Why do the planets orbit the sun? (Beginner)
What would happen if an asteroid 10 kilometers across hit the Earth? (Beginner)
What color is each planet? (Intermediate)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
How far is each planet from Earth? (Intermediate)
If gravity isn't a force, how does it accelerate objects? (Advanced)
Why can't a plane fly slowly and let the Earth pass underneath? (Beginner)
What would happen if an asteroid 10 kilometers across hit the Earth? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
What is the significance of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle? (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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