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Library of Past Questions

General Astronomy & Astrophysics

  • We no longer answer questions on this topic, to concentrate our limited resources on questions on space based astrophysics and closely related areas (see this page for more explanation).
  • Check out the resource links. These are the sites we used to point to in answering your questions.
  • Browse through the library of questions below. We may have already answered your questions.

Are you sure your question is not covered in another, more specific, page? If you're not sure what our subject categories are, check our list of categories with explanations. The answer to your question may already be on our site, if you only knew where to look!

Resources for this Topic

  1. The Astronomical Society of the Pacific (

  2. Astronomy Picture of the Day (

  3. NSSDC's GeneralPublic Page (

  4. History of Astronomy and Archaeoastronomy Links (

  5. History of High Energy Astronomy (

  6. The Talk.Origins Site (

Library of Past Questions and Answers

    Astronomy (General)

  1. What is interferometry?

  2. How cold is it in space?

  3. What units are used to measure distance in astronomy?

  4. What is a light year?

  5. What are the ways that distances are measured in astronomy?

  6. Why do most celestial bodies rotate?

    Related Areas of Physics

  1. Do the Laws of Motion apply in space?

  2. When a star (or light source) is moving away from you, does it emit blue or red light?

  3. Can you explain the gravitational potential well?

  4. What is a plasma?

  5. What are the four forces of nature?

  6. How many chemical elements are known to exist?

  7. How do our eyes see light? Is light a particle or wave?

  8. Which method is used for actually detecting neutrinos?

    Astronomy Resources

  1. How do you receive email about the latest Astronomical events?

  2. Are there any astronomy search engines?

  3. Where can I find children's Astronomy videos and other resources?

  4. How do I find specific astronomy information on the Internet?

    School Projects

  1. Can you recommend any good astronomy-related science fair projects?

  2. Can you give me a science fair idea that has to do with gravity or inertia?

  3. What are the scientific principles behind hot air balloons?

    History of Astronomy & Astrophysics

  1. Why did ancient civilizations consider astronomy to be important?

  2. What is the history of astronomy? What tools did ancient astronomers use?

  3. Who discovered that the Earth orbits the Sun?

  4. Who was the first person to prove that the Earth rotates?

  5. How did they measure planetary and stellar distances in antiquity?

    Astronomy, Society & Religion

  1. Is technology advancing too rapidly to be safe?

  2. What is the Big Bang? What do you believe?

  3. What should I tell my daughter about the creation of the Universe?

  4. Can you interpret an astronomical reference for me?

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Acting Project Leader: Dr. Barbara Mattson
All material on this site has been created and updated between 1997-2012.

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