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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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Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
What was the bright, smoothly moving star that I saw? (Beginner)
Is time travel possible? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
How does the location of sunrise and sunset change throughout the year? (Advanced)
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How can we find galaxies behind the Milky Way? (Intermediate)
When measuring the expansion of the universe, do astronomers consider that they're seeing how galaxies moved long ago, not today? (Intermediate)
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How long could life on Earth survive if the Sun stopped shining? (Beginner)
Is time travel possible? (Beginner)
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)
When was the last time all of the planets were aligned? (Beginner)
What was the bright, smoothly moving star that I saw? (Beginner)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
What is the difference between a "star" and a "sun"? (Beginner)
How far is each planet from Earth? (Intermediate)
At what speed does the Earth move around the Sun? (Beginner)
How does the location of sunrise and sunset change throughout the year? (Advanced)
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)
What was the bright, smoothly moving star that I saw? (Beginner)
How does the position of Moonrise and Moonset change? (Intermediate)
Which planet is most similar to Earth? (Intermediate)
How does the location of sunrise and sunset change throughout the year? (Advanced)
What are constellations used for? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
How far is each planet from Earth? (Intermediate)
Why do we not have eclipses every month? (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)
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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