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Bright light due south/west

  1. Dec 10, 2013 #1
    at about 45 degrees as view from south western france , this isnt a star as it doesnt twinkle
    its not a planet as it seems to be geo stationary, but is very bright and changes colours from blue / red white,, i'm sure this is just reflective light from solar panels,,,, but what is it ???
  2. jcsd
  3. Dec 10, 2013 #2


    Staff: Mentor

    Are you sure it isn't the Dog star Sirius? It would be positioned at about 30 degrees to the bottom right from the constellation Orion. It oftens sparkles with blue white/ red white colors.

    Looking at about 45 degrees to the SW at say 9pm I see the constellation Aquarius but its stars don't seem as bright.

    If you have a smart phone and the Distant Suns app or the StarMap Pro app then it might help you identify the mystery object. These apps use the built in GPS and display the sky in the direction your phone is facing.
  4. Dec 10, 2013 #3


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    Does it move in the sky over time? Or is it always in the same spot? If it's the latter, then it's not an astronomical object.
  5. Dec 10, 2013 #4
    It's Venus.
    re: "geostationary"... well, planets move very slowly against the stars, so you will not see it move in one night, other than from Earth's rotation - it will rise and set.
  6. Dec 10, 2013 #5
    Yep, it's Venus. Venus is very prominent in the SW sky, it comes to it's highest in the sky and brightest this time of year.
  7. Dec 10, 2013 #6


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    I thought geostationary meant, "stays over the same coordinates", indicating perhaps, some type of communication satellite. Am I confused? :confused:
  8. Dec 11, 2013 #7
    I think I have to go with the magnitude brightness scale venus being 4.9 sirius 1.9 as it is a pretty dam bright thing
    its got to be venus even thru I always thought venus was never more than a 33 degree arc from the sun , 8 pm puts the sun well below the horizon and mystery venus still at a 45 to a fairly flat horizon ?!?
  9. Dec 11, 2013 #8


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    Venus's maximum elongation is about 45 degrees: http://en.wikipedia.org/wiki/Elongation_(astronomy [Broken])
    Last edited by a moderator: May 6, 2017
  10. Dec 11, 2013 #9
    No, you are correct. I think the original poster is seeing the object in roughly the same place at roughly the same time every night. I would bet that it sets later on.
    Of course, a real, geostationary sat would stay in the same place and never move at any time of day.
  11. Dec 12, 2013 #10
    sorry this is setting !! its venus , isnt it big !
  12. Dec 12, 2013 #11


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    Nope! It only looks big because of how bright it is. Jupiter has a much larger apparent size but appears smaller when viewed without magnification because it is dimmer than Venus at the moment.
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