Answers edited by Alexander W. Smith

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• Why do massive stars die?
  
• Which way does the earth rotate: east or west?
  
• What is the proof for existence of black holes?
  
• Who were the little rock nine ?
  
• What features of an alien planet would you look for in order to determine if the planet experiences plate tectonics?
  
• What are the different galaxies in space?
  
• How do the sun, stars and galaxies work together?
  
• How long ago was the world created?
  
• How many galaxies do astronomers estimate there are in the Universe?