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String of satellites transits moon?

  1. Sep 29, 2010 #1
    I was out observing tonight with my Orion Skyquest 8" Dobsonian. I was observing the moon, when I happened to notice a string of satellites transiting the moon. It is not abnormal for me to observe satellites in earth orbit that transit the moon with my scope but it is usually one at a time. I did not have time to count them but they appeared something like this.


    ssss ssss ssss

    It was either three or four in a row separated by a bit of space, like I have illustrated above. Does anybody have an idea of what these satellites are and what they are used for?
     
  2. jcsd
  3. Sep 29, 2010 #2

    russ_watters

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    If you give me precise details of the observation, I can positively ID the satellites for you:
    Location.
    Exact time.
     
  4. Sep 29, 2010 #3
    Location was slightly SE 45° 2629' North 122° 693' West. The time is a bit tricky as I had temporarily lost my phone in the field I was observing at but my best guess would be around 10:05pm - 10:35pm.
     
  5. Sep 29, 2010 #4

    russ_watters

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    So that's near Portland, OR? I have the moon rising after midnight.

    [edit] Er, wait - it was pulling the time zone from Windows. I still have it rising around 10:30, unless you don't do DST there. But I'm not seeing any satellites coming close to it around that time.
     
    Last edited: Sep 29, 2010
  6. Sep 29, 2010 #5
    I was observing right when the moon was rising as the horizon at my location was very low. It definitely could have been later, I tried to find them on Starry Night Pro Plus 6 to no avail (although it seems to me that the timing is a bit off). And given their vector they had to be in orbit and not inside the atmosphere. It was just the grouping that confused me. Thank you for help anyway!
     
  7. Sep 29, 2010 #6

    russ_watters

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    I'm using Starry Night 5. I didn't see any transits that night at all. It is possible they were too dim to be displayed by Starry Night (you would have seen it sillouhetted).

    There is all sorts of crap up there - often when a rocket goes up a booster will end up in orbit with the satellite it launched, at least for a while. I've particularly noticed with the ISS that there is often a trailer or two with it.
     
  8. Sep 30, 2010 #7

    collinsmark

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    Is it possible to rule out a flock of birds in the distance (you mentioned the moon was very close to the horizon)? I know you mentioned, "given their vector they had to be in orbit and not inside the atmosphere." But it is conceivable that if earthbound objects were flying somewhat toward or away (most likely away in this case) from the observing point they might appear, through the telescope, to have an inclination similar to objects in orbit.
     
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