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Unexplained light.

  1. Aug 23, 2005 #1

    matthyaouw

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    I just saw a light in the sky that I can't explain, and I was wondering if you could help at all.

    At approx 11:30 pm (British summer time) I noticed what seemed to be a very bright star in the west, reasonably low in the sky (perhaps 30-40 degrees from the horizon). The light grew for a few seconds, becoming brighter and larger than any star I've ever seen, before diminishing into what looked like an ordinary star, and then nothing. The whole thing took no more than 10 seconds.

    It was too bright to be an aircraft, and lacked the sweping motion of the police helicopter's searchlight, plus i was unable to see any flashing aircraft lights afterwards.

    Can anyone suggest what I might have seen?
     
  2. jcsd
  3. Aug 23, 2005 #2

    Danger

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    It might not have been too bright to be an aircraft if you consider multiple high-intensity landing lights that are close enough together to appear as a single source. If the plane were to climb or dive while still heading toward you, they would appear to dim and then disappear.
    It could also have been a meteor that was heading directly toward you before burning out (in which case it's a bloody good thing that it disappeared).
     
  4. Aug 24, 2005 #3

    ek

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    Feel your neck. Any bumps or sores?

    Just kidding. I really don't know what it could have been.
     
  5. Aug 24, 2005 #4

    ek

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    I think that's a pretty good guess. That fits his description perfectly.
     
  6. Aug 24, 2005 #5

    Tide

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    Matt,

    Depending on how far north you are and how far west you are in your time zone, it could simply have been the planet Venus with some fancy atmospheric scintillation. Venus would have been in the west and close to the horizon at that time.

    Do you have daylight savings time in England?
     
  7. Aug 24, 2005 #6

    matthyaouw

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    Both good points, thanks. I'd considered aircraft light briefly, but the meteor I hadn't thought of. Do aircraft always have their landing lights on, or do they switch on when close to the ground? I'd worry severely if an aircraft were trying to land in these parts.

    we do have daylight savings. It would have been 10:30pm Greenwich mean time. I've marked my position on this map with a red dot half way up Britain's east coast. Would that be about right to see Venus there?

    [​IMG]
     
  8. Aug 24, 2005 #7

    Tide

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    Matt,

    No, I just ran Stellarium and 10:30 is too late to see Venus. However, Arcturus (mag. = -0.3) is in that region of the sky at about 25 deg north of west and 10 to 25 deg above the horizon depending on the exact time.
     
  9. Aug 24, 2005 #8

    matthyaouw

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    I'm not sure. I've looked up atmospheric scintillation briefly, and found that it causes twinkling, but the source (wikipedia) doesn't explain how a sustained flash of such magnitude could be produced; I mean this was seriously bright. Has it been known to cause such flashes in the past?
    I think Arcturus is unlikely, being that it is quite a bright star, and the light source dissapeared after the flash, even though I could still see other stars.

    Forgive my lack of knowledge on astrology, as the subject is pretty new to me.
     
  10. Aug 24, 2005 #9

    Danger

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    :surprised :eek: :bugeye: :surprised



    Forgive my shock. Aircraft do not normally keep their landing lights on while in normal flight, but occassionally a pilot will simply forget to turn them off or for some reason wants more visibility to others than his beacons provide. (Such as to alert oncoming craft who request it.)
     
    Last edited: Aug 24, 2005
  11. Aug 24, 2005 #10

    matthyaouw

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    Ology, onomy, same thing (alright not the same thing, but you knew what I meant) :P
     
  12. Aug 24, 2005 #11

    SpaceTiger

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    If the effect was as dramatic as you describe, it couldn't have been atmospheric scintillation. I would put my money on something of human origin, though a meteor is possible as well.
     
  13. Aug 24, 2005 #12
    There can be an increase glare from:http://spaceflight.nasa.gov/realdata/sightings/cities/viewsighting.cgi?Aberdeen.html

    due to your position with respect to ISS, the time of the glare would obviously depend on the Sun?

    This does not correspond to your time, but there are other metalic objects up there that can create short burts of light?
     
    Last edited: Aug 24, 2005
  14. Aug 24, 2005 #13

    matthyaouw

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  15. Aug 24, 2005 #14

    Tide

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    Matt,

    Here's a another possibility. One summer long ago I was sitting out on a beautiful clear night watching the Perseid meteor shower. I happened to have a pair of binoculars with me and, for a while, I was looking through them and examining the region of the sky within the constellation Perseus.

    While I was looking I was astonished to see a light suddenly flash on and grow VERY bright over the course of a few seconds and then it faded out fairly quickly. What I had seen was a meteor whose velocity was directed straight toward me! I just happened to be looking at the radiant of the Perseids when one popped out.

    What you saw sounds a lot like what I had observed.
     
  16. Aug 29, 2005 #15

    mu

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    I can't be sure 100%, but it looks like you saw an Iridium flare. I've seen them on many occasions. Normally you have to know where and when to look as they only last a few seconds. You can see a list of flares (always up to date) at http://www.heavens-above.com/
     
  17. Aug 30, 2005 #16

    Chronos

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    I like the flare interpretation. A very plausible explanation that fits.
     
  18. Aug 30, 2005 #17

    Danger

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    I've never heard of that flare bit before. Thanks for the info. I'll keep an eye out once in a while.
     
  19. Aug 31, 2005 #18
    It sounds like an Iridium flare to me. I've seen one before and that is exactly what it looked like, although as far as I know they wouldn't occur that late at night.
     
  20. Sep 1, 2005 #19

    matthyaouw

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    I've just checked the database, and there was an iridium flare at that time, in roughly the right direction and height that I was looking at. That is most likely what it was. Thanks everyone!
     
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