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Blue Stragglers
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What are "blue stragglers" in globular clusters?
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What would happen if two stars collided?
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Can superheavy elements (such as Z=116 or 118) be formed in a supernova? Can we observe them? (Advanced)
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Is speed of light the same everywhere ? (Beginner)
How does Venus have sulphuric acid in it's clouds? (Beginner)
Earth's Bow Shock (Advanced)
How much does the Earth "wobble" on its orbit due to the Moon's gravity? (Intermediate)
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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Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
Is it possible to see the full Moon and the Sun simultaneously in high northern latitudes when the Sun doesn't set? (Intermediate)
How do we know what we observe is x light years away? (Beginner)
How does Venus have sulphuric acid in it's clouds? (Beginner)
What is the evidence supporting the nebula theory of Solar System formation? (Intermediate)
How big a change in the Earth's orbit would be required to destroy all life? (Intermediate)
What's going to happen on December 21st 2012? (Intermediate)
Why is the Universe flat and not spherical? (Advanced)
Can we look back far enough in time to see the Big Bang? (Beginner)
What's the difference between astronomy and astrology? (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)
What was the bright, smoothly moving star that I saw? (Beginner)
How does the position of Moonrise and Moonset change? (Intermediate)
How long could life on Earth survive if the Sun stopped shining? (Beginner)
How far is each planet from Earth? (Intermediate)
Which planet is most similar to Earth? (Intermediate)
What is the difference between a "star" and a "sun"? (Beginner)
At what speed does the Earth move around the Sun? (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)
What was the bright, smoothly moving star that I saw? (Beginner)
How does the position of Moonrise and Moonset change? (Intermediate)
How does the location of sunrise and sunset change throughout the year? (Advanced)
Which planet is most similar to Earth? (Intermediate)
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 the planets orbit the sun? (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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