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Satellite or something else?

  1. Oct 13, 2004 #1
    It was a little after sunset and I noticed a star at an Altitude of about 90 degrees. It wasn’t moving and it looked like any other star, but all of a sudden it started to get dimmer. I thought maybe a cloud was passing over, and there were a few small clouds around, but none I could see directly covering this particular star. Apart from a few small clouds the sky was very clear. I think I watched for maybe another 30 – 60 seconds as this star totally disappeared.

    I’m thinking whether it could have been a geostationary satellite, but I only know of these satellites to hover over the equator, and I’m nowhere near the equator. It would have been a few years ago now, and I’m still wondering what it was.

    Can anyone tell me if a geostationary satellite could hover over a location apart from the equator or whether it could have been something else?
  2. jcsd
  3. Oct 13, 2004 #2
    I’ve seen many satellites before, iridum flares, the ISS. I’ve never seen a geostationary satellite, so I wouldn’t know whether they fade in brightness in the same way a typical moving satellite would. This is anywhere from a few seconds to a whole minute as the satellite passes into the earths shadow. My guess is that a geostationary satellite would fade over the course of a few minutes, if someone has any idea it would be much appreciated!
  4. Oct 13, 2004 #3

    Ivan Seeking

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    Approximately where are you located? When you say 90 degrees, do you mean 45 degrees? 90 degrees is straight up...
  5. Oct 14, 2004 #4
    I’m in Perth, Australia and it was close to 90 degrees straight up.

    What’s bothering me is that it faded like an ordinary satellite, though how could it have been if it was stationary? I noticed it because it was quite bright to begin with, about as bright as Jupiter. The only alternative I can think of is that it was in the upper atmosphere and moving extremely slowly.
  6. Oct 14, 2004 #5


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    Maybe it was slowly rotating?
  7. Oct 14, 2004 #6
    What a satellite or a high altitude aircraft? Satellites do rotate, and you’ll see them increase and decrease in brightness as the solar panels direct sunlight in your general direction, it would make sense if it was stationary, but as far as I know nothing in orbit can have a stationary position unless its over the equator.

    Those are the two factors: either it moves into the earths shadow or rotates out of view. This ones truly got me stumped!
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