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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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What what a black hole merger look like from a telescope? (Advanced)
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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)
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Why is looking out into space the same as looking back in time? (Beginner)
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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 long could life on Earth survive if the Sun stopped shining? (Beginner)
When was the last time all of the planets were aligned? (Beginner)
How do you measure the distance between Earth and the Sun? (Intermediate)
If gravity isn't a force, how does it accelerate objects? (Advanced)
How does the position of Moonrise and Moonset change? (Intermediate)
What would happen if an asteroid 10 kilometers across hit the Earth? (Beginner)
Why do the planets orbit the sun? (Beginner)
At what speed does the Earth move around the 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 does the position of Moonrise and Moonset change? (Intermediate)
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)
Why do the planets orbit the sun? (Beginner)
What is that ring (or rainbow) around the moon? (Beginner)
At what speed does the Earth move around the Sun? (Beginner)
Which planet is most similar to Earth? (Intermediate)
Can artificial gravity be created in space? (Intermediate)
If gravity isn't a force, how does it accelerate objects? (Advanced)
How do you measure the distance between Earth and the Sun? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
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)
Can artificial gravity be created in space? (Intermediate)
Are there telescopes that can see the flag and lunar rover on the Moon? (Beginner)
Which planet is most similar to Earth? (Intermediate)
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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