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Library of Past Questions

The Night Sky

  • 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.

Resources for this Topic

  1. StarDate Online ( including their monthly sky almanac, Stargazing (

  2. The Constellations and their Stars ( by Chris Dolan

  3. An Online Astronomy Course for Middle School and High School Students (

  4. Sky & Telescope magazine, and their online site, ( including this week's sky at a glance, ( their maps and charts ( page, binocular and telescope ( guide, and other tips for backyard astronomers (

  5. Abrams Planetarium Skywatcher's Diary (

  6. Amateur Astronomy on the Net ( - the Astronomical Society of the Pacific's list of online astronomy resources

  7. The Mythology of the Constellations (

  8. "Peterson Field Guides: Stars and Planets," by Donald H. Menzel and Jay M Pasachoff. (Highly recommended - available in book/nature stores.)

  9. "Turn Left at Orion: A Hundred Night Sky Objects to See in a Small Telescope - And How to Find Them," by Dan M. Davis, Guy J. Consolmagno, Daniel M. Davis, Cambridge Univ Pr (Trd); ISBN: 0521482119

Library of Past Questions and Answers

    Observing the Skies

  1. What was the object I saw, which brightened and faded quickly?

  2. Why is the sky blue and why is the Sun red at sunrise and sunset?

  3. Why is space black?

  4. How would you recommend that I go about purchasing my first telescope?

  5. What magnification do telescopes need to photograph galaxies?

  6. How can you measure the amount of light pollution in the sky?

  7. Why do the stars appear to twinkle while the planets don't?

    The Moon and the Planets

  1. Are there special names for the first full moon of each month?

  2. Why does the Moon looks much larger near the horizon (at moonset) than in the middle of the sky?

  3. Why does the Moon looks white in daytime while it is yellow at night?

  4. Why did the moon turn red during the last lunar eclipse?

  5. What causes a ring to appear around the moon?

  6. What are Sundogs and Moondogs?

  7. Are there planet charts?

  8. Would you know a place that I can find out the positions in degrees of the planets on a given day?

  9. How do you calculate the positions of planets from any point on Earth at any given time?

    Stars and Constellations

  1. Where can I get a chart of the Southern Skies?

  2. How do the stars move in the sky?

  3. What are the three brightest stars in the Summer Sky?

  4. How many stars are there, named and un-named, known to exist?

  5. Are the stars we see at night all from our own galaxy? How many stars are in our galaxy?

  6. How bright is Antares?

  7. Can you tell me about Fomalhaut?

  8. Could you give me the names of all the stars in the constellation Pegasus? What about other constellations?

  9. Was the present North Star Closer to the pole in 44 B.C.?

  10. Where are the Pleiades located in the sky and the myths that go along with them?

  11. What determines the starting point of the stellar magnitude scale?

  12. How did the stars get their names?

  13. What is the best way to learn how to find the constellations?

  14. Which constellation is directly behind the Sun when the Sun rises?

  15. Where can you find Sagittarius in the sky on winter and summer nights?

  16. What would the constellations look like if they were viewed from someplace other than Earth?

    Other Night-time Objects

  1. What is a shooting star?

  2. What are the dates of annual meteor showers?

  3. How did the Milky Way get its name?

  4. What is the tale of the two lovers kept apart by the Milky Way?

  5. When is the best time to view a comet?

  6. Can you see satellites with the naked eye?

  7. Where can I find a list of all the visible satellites?

Imagine the Universe is a service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center.

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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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