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Mysterious Night Sky Object - Help?

  1. Jun 18, 2012 #1
    Mysterious Night Sky Object - Help!?

    Well, I've commented on others' questions on a number of occasions, but something just occurred which has thrown me for a loop, and I could really use an opinion or two. I've been into amateur astronomy for 43 years, and have seen any number of very interesting objects--all of them explainable--until now. I live in Mesa, AZ (roughly 33 deg. north/111 deg west) and was relaxing in my darkened back yard facing due south. Every once-in-a-while I began to notice a brief flash of light, high up in the sky, south of zenith. Each flash was very brief--perhaps a tenth of a second--and the more I watched the more it seemed they were regular, but too far apart to be a plane, etc. I timed the interval, and it occurred like clockwork every 36 seconds. After a time I went in to get a pair of 10x50 binoculars, and focused them on the location. The flash was still there, but there was no discernable object at that spot in between flashes. Another odd thing was this: I watched the flashes for roughly 45 minutes, and during that time the object did not shift its relative position to me, while the star field slid 10+ deg. to the west. It seemed to remain due south of me, and roughly on the celestial equator, so 33 deg. south of my local zenith. The flash intensity remained constant, at roughly mag. +2, and the color was white. This took place between 9:30pm and 10:15pm my local Mountain Standard time (no DST). I can't imagine that this is the case, but for all intents and purposes it was behaving like a geo-sync satellite at 111 deg. west. Maybe DirecTV has taken to using lasers for data transmission? All I can say is very, very odd. Thoughts? Conjectures? Ridicule??
     
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  3. Jun 18, 2012 #2

    Bobbywhy

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    Re: Mysterious Night Sky Object - Help!?

    Maybe a beacon atop the 2500 foot San Tan Hills?
     
  4. Jun 18, 2012 #3
    Re: Mysterious Night Sky Object - Help!?

    I'd have to guess the source is somewhere on Earth, due to the fact that it didn't shift at all relative to you.
     
  5. Jun 18, 2012 #4

    Borek

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    Re: Mysterious Night Sky Object - Help!?

    Geostationary would not shift.
     
  6. Jun 18, 2012 #5
    Re: Mysterious Night Sky Object - Help!?

    As the 'object' didn't move in relation to you, I would have to guess that it was from Earth. A lighthouse, perhaps! All jokes aside, I positively have no idea.
     
  7. Jun 18, 2012 #6
    Re: Mysterious Night Sky Object - Help!?

    I have to admit, this was a weird one. I'm in the middle of the desert, with no mountains in the near vicinity. And this was high up in the sky, much closer to overhead than to the horizon. Let me ask this, then: Although I was being somewhat tongue-in-cheek when I said this, is there any possibility that sunlight glint from a slowly rotating geo-sync sat. could be seen from the ground? If an 'Iridium flare', which I've observed many times, can reach mag. -8, and they orbit at roughly 500 miles and don't even have to be 'overhead' to produce a flash that bright, what would the inverse square law do to the light from a similar reflection at 22,300 miles? Could it still be +2 or +3 mag. from that point? This was, after all, not long after local sunset--it was dark but still during a time that I could observe many other lower altitude satellites. I intend to go back out tonight, at around the same time, and look again. If it is still there, I will try to come out with better coordinates and post them, and I will also officially freak.
     
  8. Jun 18, 2012 #7
  9. Jun 18, 2012 #8
    Re: Mysterious Night Sky Object - Help!?

    Well, that is just plain crazy. Thanks for the link. I ran the math, and by my calculations using something like a -8 magnitude Iridium flash at 500 miles altitude as a baseline, something with the same relative brightness should EASILY be visible in a goesync orbit. And, it is clearly rotating slowly at roughly 2 rpm, based on the repitition rate. Weather satellite? Discarded second or third stage from a deep space mission? I know the Directv sat. is at 110 deg. west, and I thought there was a Dish sat. at the 111 slot, but I forget now. Anyway, I'm going back out right now [for a swim -- 113 deg. today :) ], and in about 45 minutes I'll turn off all the lights and see what I see. I'm not holding my breath but anything's possible. "Phoenix Lights II"!
     
  10. Jun 18, 2012 #9
    Re: Mysterious Night Sky Object - Help!?

    Okay, folks--this is just too weird. I walked out, looked up, and the object is still there, clear as day. Flash frequency is: 43.38 seconds, like clockwork, magnitude maybe a little brighter as I came from a well-lit house and did not have to wait for my eyes to adjust. It is definitely on or very near the celestial equator, so geosync looking more likely. Here is the data:

    At 4:05 am 6-19-2012 GMT, (10 minutes ago, or 9:05 pm 6-18 local MST) the location is Declination 0.00 or nearly that, Right Ascension 14H 20M in the constellation Virgo. I'm using the star HIP 70081 as a reference point, in Stellarium, but of course that only applies to that minute. Azimuth for me is roughly 183 deg, and altitude is +56 deg 25 min, and that is where the thing stays regardless of the time. My location is 33 deg 24 min north, 111 deg 35 min west. As I said, flash frequency is 43.38 seconds. Brightness is at least mag. +2. Relatively speaking, using the distance from Saturn to Spica as a ruler, it is roughly 3 times that distance above and to the left of Saturn, at that moment in time.

    That's all I got, so someone much smarter than I will need to help answer this. Sure would be nice if someone using those coordinates could confirm the sighting! Thanks.
     
    Last edited: Jun 18, 2012
  11. Jun 19, 2012 #10

    jimgraber

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    Re: Mysterious Night Sky Object - Help!?

    Just a thought: Someone (You maybe? Sorry, not me) could compute the time a geostationary satellite would disappear due to earth eclipse or earth shadow. Then you could check tomorrow night and see if it disappears at approximately the correct time. If you watch until it disappears or all night if it doesn't, you get another powerful data point.
    Best
    Jim Graber
     
  12. Jun 19, 2012 #11

    jimgraber

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    Re: Mysterious Night Sky Object - Help!?

    Crude approximation:
    Based on being at the equator on the equinox (Which are both very wrong).
    A geosynch satellite should appear at sunset, ie 6:00 pm local time.
    It should disappear when sine of angle from satellite to edge and center of earth is
    4000/(22,300 + 4,000)= roughly 1/6.
    This is about 11:00 pm
    Someone should check my math and do a real 3d calculation based on actual date and location.
    Good Luck!
    Best again.
    Jim Graber
     
  13. Jun 19, 2012 #12

    jimgraber

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  14. Jun 19, 2012 #13
    Re: Mysterious Night Sky Object - Help!?

    Interesting thought. I may check tomorrow later and see what happens. I'm wondering, this close to the summer solstice, whether geosync satellites would see shadow at all. I have this mental picture of a ring of satellites, poised over the equator but that far out--the ring would be tilted far above the ecliptic or plane of the solar system 'behind' earth and far below the ecliptic in front or sunward. In the former case I wonder how far out an object would have to be to catch the rays passing over the north pole at midnight... I don't know--I just play these mental games. I did look for the object in question, however, at about 6 am GMT (11 pm my time) and couldn't locate it. So either I was just plain tired (possible) or the thing was in fact in shadow (perhaps more possible). I do want to do a little research on whether any of the current generation of modern geosync satellites 'rotate'. I'm picturing these big boxy birds with 100 foot solar arrays--not like the 'drums' of old. Maybe--just not sure. Thanks for all the input!
     
  15. Jun 19, 2012 #14
    Re: Mysterious Night Sky Object - Help!?

    I'm thinking that you are seeing Chinese GPS satellites that went up a month ago. Compass M3 or M4. The older Beidou satellites are geosynchronous but they are over China. I haven't been able to get the coordinates for M3 and M4.
     
  16. Jun 19, 2012 #15
    Re: Mysterious Night Sky Object - Help!?

    Some more googling, and I think you've got Sirius satellite radio orbits. Those are set up to be in tundra orbits, and they look like what you are seeing.

    http://www.tiger-usa.com/sirius-xmorbitanim.gif
     
  17. Jun 19, 2012 #16
    Re: Mysterious Night Sky Object - Help!?

    Only thing with that is that Compass M3 and M4 have orbital inclinations of + and - 55 degrees.

    "China is ready to conduct its next Orbital Launch from the Xichang Satellite Launch Center - using a Long March 3B Launch Vehicle to deliver two Beidou 2 Navigation Satellites to Orbit. This will be be first dual payload flight for Beidou Satellites. Launch is set for Sunday, April 29, 2012 at around 20:40 GMT. The satellites will be launched to an orbit inclined 55 Degrees to either side of the equator."

    This clearly sits in or near the goesync ring... I just looked at pictures of every listed satellite within + or - 5 lateral degrees of the -111 slot which would be due south for me, and all 20 something of them are the newer box version with fixed wings. I was hoping an old GOES or something, but nothing there. Unless it's an old one tumbling in the 'disposal' orbit a few hundred miles farther out. I'm at a loss at this point. I guess I'm --"just another person who THOUGHT he saw a UFO." --James T. Kirk
     
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