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Satellites in the night sky?

  1. Apr 8, 2008 #1
    One summer night in 2005 I was out on my roof with a couple of my friends, and the sky was perfectly clear. We could see thousands of stars, it was amazing. We were in the countryside far away from any city lights.

    Well, the entire night we were just star gazing and every 5 minutes we would see a "shooting star" (or that's what we thought at the time). The light would streak across the sky, so if you were looking directly up at the sky (90 degrees), the streaking lights would zip by from west to east.

    Is it possible to see at least 20 shooting stars in one night, or were the streaking lights in fact satellites? How often do satellites pass? How many satellites orbit the earth?

  2. jcsd
  3. Apr 8, 2008 #2

    D H

    Staff: Mentor

    Satellites are slow: Six minutes or so to cross the sky if the go straight overhead. If it zipped by, it was a shooting star.
  4. Apr 8, 2008 #3


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    Staff Emeritus
    Science Advisor
    Gold Member

    Satellites are almost a little eerie when you first spot them. They appear to move relatively slowly -- airliners usually appear to move significantly faster. They move in such perfect arcs and with such steady speed that sometimes you spot one and think your mind is playing tricks on you.

    Meteors, on the other hand, usually last only seconds. They can and do occur at all hours of the day and night. Seeing a dozen or more over the course of an evening under dark skies is not exceptional.

    - Warren
  5. Apr 8, 2008 #4


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    Staff: Mentor

    ....and seeing a dozen or more satellites over the course of a dark evening is not exceptional either.

    One thing about satellites: since to see them they need to reflect sunlight, you will see the most for a few hours after sunset and before sunrise.
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