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Q13: A nebula that emits its own light
Q21: The capture of free neutrons by heavy
Q55: How is the length of a star's
Q60: You are trying to determine the age
Q62: What is an elliptical galaxy?<br>A) A galaxy
Q63: If you triple the distance to a
Q65: One proposal for the mysterious dark matter
Q93: What do cosmologists study?<br>A) The origin,structure,and evolution
Q104: New stars are formed<br>A) in huge,cool dust
Q105: Approximately 10% of the mass of the