Monthly Archives: December 2012

The Composition of the Universe

Question:  Is it true that we only know 10% of the universe and the rest is dark matter, though if we only know 10% we don’t even know how big are universe is?  — Lily Answer:  I think that you … Continue reading

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Can a Black Hole Swallow a Galaxy?

Question:  I know that black holes are very dense and their gravitational pull is so strong no one really knows what they look like because they don’t come out alive. I have read that there might be one in the … Continue reading

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The Solar System’s Rotation About the Center of the Milky Way

Question:  I have a question about galaxies, how do scientist know about the galactic year and how long it takes? Well people think that are universe is only 14 billion years old has our solar system gone through a galactic … Continue reading

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The Properties of Spiral Galaxies, Including Our Own

Question:  Me and the rest of our fifth grade class is learning about galaxies, but I have a couple questions. Why is the middle of a spiral galaxy bigger than the arms? How fast is our Galaxy moving, is it … Continue reading

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The Difference Between Theory and Observation in Astronomy

Question:  For my senior research project I am doing what aspects of astronomy are theory and what are fact. The question I pose is what are different theories I could use for this topic? I already have the theory of … Continue reading

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What are Constellations?

Question: My class and I are working on a class project about constellations so I was wondering if you could answer some of my questions. The first question that I have is what is a constellation. The second question that … Continue reading

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Millimeter Wavelength Signals and “Light”

Question: Several of your articles about ALMA refer to millimeter-wavelength signals received by the radio telescope as “light.” I understand that these signals exhibit many of the characteristics of light such as diffraction, but at wavelengths longer than infra-red, is … Continue reading

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