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Baffled by observation -- 3 lights in the night sky

  1. Jan 23, 2015 #1
    Hi! :) This is my first message here.

    The reason I joined this forum is because there are some knowledgeable people here who might be able to shed some light on an observation that I cannot explain. It happened during the night of July 28, 2013, at around midnight, and it still keeps me pondering.

    It was a warm, clear night and I was sitting in my parent's garden with my neightbours, parents and a friend.

    I was stargazing a bit inbetween conversations, as I typically do on such a night. I did not have any visual aids.
    Satellite flares were clearly visible and I pointed them out every now and then.

    Suddenly my eye fell on what appeared to be three white dots of light straight overhead. They were somewhat brighter than the average star, but less bright than the brightest stars. There was no apparent atmospheric twinkle either. They were traveling in a rigid delta formation, further apart than typical airline strobes. At first I thought it might be faint lights on the underside of a large military airplane. I called out to everyone and pointed at the lights. Everyone could see them except for my dad, whose eyes were probably still adjusting to the darkness.

    Within about five seconds the delta appeared to rapidly expand and engage in fluent maneuvers. Up until that point, I was convinced that they were part of one solid object. That was also the point where I realized this was unlike anything I'd ever seen in my many nights of stargazing. Everyone was completely baffled. I ran over to a darker corner of the garden in hopes of getting a better view. The objects converged back into a delta and continued their path in the same direction, towards the northeast. They were moving at significant speed and soon went out of sight. All throughout there was no sound or change in their brightness.

    Now, I'm an aviation enthousiast, and this was unlike what any airplane is capable of. It was reminiscent of the maneuverablitiy of multirotor rc helicopters which I happen to fly.

    I spent the next two hours watching the sky but they did not appear again. It was the first time I could literally not think of any explanation for what I'd seen, and I haven't seen anything remotely like it before or since. Neither did anyone else who was there.

    Also, I'm glad that I wasn't the only one who saw this, else I'd probably never mention it again. I have no video or photo, as it all happened very fast, and was probably too faint to show up on smartphone video anyway.

    I have included a simple drawing of what it roughly looked like.

    Does anyone happen to know of atmospheric phenomena that might manifest in such a fashion?
    Has anyone witnessed something similar?

    Enlighten me with your knowledge and speculation. :)

  2. jcsd
  3. Jan 23, 2015 #2


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    Welcome to the PF.

    Sounds like military fighter jets at high altitude.
  4. Jan 23, 2015 #3


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    yup, that was my initial conclusion too, flying in formation, breaking formation and then returning

  5. Jan 23, 2015 #4


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    To avoid the airliner without unnecessary risks to pilots.
  6. Jan 23, 2015 #5


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    This is a common claim by people who see strange things in the sky. Unfortunately, you cannot rely upon your intuition in these matters. It is essentially impossible, even in the daytime, to accurately tell how far away, how fast, or in precisely what direction an object in the sky is traveling. Something that seems to 'accelerate faster than a man-made object' could simply be an aircraft turning so their heading is perpendicular instead of mostly towards/away from you. You may not be hearing anything because they are too far away or because they have different engines which don't produce as much noise.
  7. Jan 27, 2015 #6
    Thanks for the responses.

    I can see how one might attribute the sighting to military jets. However, I remain unconvinced.

    There are several reasons for this:

    There was no sound whatsoever. I've frequently observed military aircraft at night (I live close to a military airport, though this was at my parents house). They are typically very audible to high altitudes, always use strobes, and have visible afterburner glow. Their appearance also changes depending on their orientation. It remained uniform throughout what I saw.

    In order not to be audible they had to be flying at extremely high altitudes, well in excess of any commercial jetliner. A commercial jetliner passed overhead minutes after the observation. My parents live in a small, very quiet town, and it was clearly audible. Three military jets engaging in seemingly remarkable feats of maneuverability would produce a lot more sound than a commercial jetliner in level flight at cruising altitude. I strongly doubt they would maintain the same maneuverability at such atltitude. In fact, I have never seen military aircraft this maneuverable. But then again, I'm used to seeing F-16's train at night. They are loud, slow and always use strobes, nothing like what I saw. What I saw was essentially three silent, star-like 'dots' rapidly change direction and reform. There also appeared to be no point to it whatsoever, which frustrates me the most.
  8. Jan 27, 2015 #7


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    That really isn't a reality. At medium altitude and above, most planes are silent. I live only 20 miles from Philadelphia airport and I don't hear any of the planes that fly over, even though they are probably only at 10,000 feet (though they are at reduced power as they are decending).
    That is true, but at high altitude or at an unusual angle, they may be tougher to see.
    Military jets only use afterburner when taking off and during high energy maneuvers -- they use way too much fuel to use continuously.
  9. Jan 27, 2015 #8


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    So I tried to put some numbers on it, and I'm not sure if I'm doing it right. The values are a bit crazy.

    The measured sound intensities (normalised for human ear) for the noisier variants of F16 jets at full military (no afterburner) take-off power is about 110dB from 1000ft. About 20dB less for approach/landing, and something in-between for level flight and non-acrobatic manoeuvres - probably towards the lower end. Afterburners add only about 5 dB.

    Sound intensity follows the inverse square law, so 10 times farther it'll be 100 times weaker. 10n intensity difference corresponds to n x 10 dB.
    This means that every power of 10 of the distance changes sound intensity by 20 dB.

    We're looking for a distance from which the sound would be no louder than about 40 dB - the background sound in a quiet library. Let's say it's comparable to a quiet night with other people around.

    So, a fighter jet in cruise flight would be inaudible beyond about 300 000 ft in a straight line (~60 miles).

    Furthermore, according to these calculations, a fighter jet in a dogfight(+20dB) would have to be audible from across a typical state, which seems absurd. But perhaps that is the result of not taking into account accumulated dissipation due to air non-uniformity, surface reflections and maybe earth curvature.

    But, if we were to assume the 60 mile figure to be correct, then the whole 5 second-long manoeuvre performed at 0.5 Mach would have to visually fit in an area the radius of the Moon (using small angle approximation and assuming the time estimate to be correct). I'm going to guess the OP will tell us it was much larger.

    Anyway, unless there's a fundamental flaw or a cock-up in the above, or the input data is grossly inaccurate, I'd tentatively conclude these were not high-powered jet fighters. Could be pretty much any other kind of planes, though.
  10. Jan 27, 2015 #9


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    I don't know what to tell you other than just repeat that I've watched thousands of airplanes fly over over my lifetime and most are inaudible. Two general comments:

    1. When making a calculation where you don't know some major input values, you can spend a lot of effort and be highly confident in a wrong result. My boss likes to say it as "wrong with aabsolute certainty". It is a big trap people, particularly science types, often fall into. Obvious pitfalls here include atmospheric attenuation, wind, the Doppler effect and aspect differences in noise generation. A quick Google tells me that attenuation is anywhere from 0.2-2.8 db/100m, depending on frequency and humidity. That's easily enough to make a jet in afterburner potentially inaudible at 10km.

    2. When it comes to UFOs - or illnesses, for that matter - it is much more likely that you are seeing something common but behaving in an unusual way, than something exotic. So any mundane explanation that seems unlikely due to certain specific unusual traits, but fits the general observation, should be considered highly likely, not highly unlikely.

    My first thought here was also high altitude fighters. The lack of other lights and noise really isn't that unusual.
    Last edited: Jan 27, 2015
  11. Feb 1, 2015 #10

    jim hardy

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    mine too.

    Military only has to follow civil aviation rules when in civilian airspace. I think below 40 thousand feet..
    I witnessed a near-miss in 1982 shortly before that agreement was made.

    At 80,000 feet anything goes - no lights, no speed limit.
    Did you read the Aviation Week Pilot's Report on SR71?

  12. Feb 1, 2015 #11


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    Being outside at midnight suggests summer in a warm climate, northern hemisphere. That would make the satellite flares you report improbable since low orbit satellites would be in the Earth's shadow, like you.

    One possibility would be re-entry of space junk. Another would be directly approaching meteor(s).
    Take a look at; http://en.wikipedia.org/wiki/List_of_meteor_showers
    We need to know your latitude to work out which constellation would be “overhead” at midnight on 28th July. Notice a profusion of meteors expected between 26th and 29th July.
  13. Feb 8, 2015 #12


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    Satellite flares can be visible more than two hours after sunset - the Iridium satellites are at an altitude of ~780km.
    I don't see how meteors or space junk would give the initial formation.

    Jets at high altitude sound like a very reasonable explanation. You don't hear them due to attenuation in the air and they can easily fly twice as fast as commercial airplanes (or even a bit faster if they are higher up). The described pattern fits to typical flight maneuvers.
  14. Feb 9, 2015 #13
    Please note that the rough timeline I included in the drawing is supposed to give you an idea of how fast this happened. The objects literally needed less than a second to change their heading by around 90 degrees. That's why it baffled us. It was as though they instantly changed direction in manner that to me looked similar to quadcopter motion, like a zigzagging motion, except that they only did this once before returning to their previous formation. Like three swallows breaking formation to dodge an eagle before regrouping, except that these were obviously not birds. If I was even slightly convinced that I could attribute this observation to high altitude jets, I would have settled for that and not even mention it here. For now I will be reading up on recorded instances of unusual observations and atmospheric phenomena.
  15. Feb 9, 2015 #14


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    It would still be useful to know the observers latitude to the degree. That will help reduce the possibilities by identifying the altitude if the lights were reflected sunlight.

    Unidentified lights in the sky are unidentified because there is insufficient reliable uncontaminated data available. The less good data there is, the more open and fascinating the analysis. When there is almost no known good data, there are some who will irrationally take that as proof of extraterrestrial visitors. But we can apply the ET UFO analysis in another way. What evidence is there as to why the formation could not have been three computer algorithm controlled quadcopters at a low altitude.
  16. Feb 9, 2015 #15
    Latitude of the location was 51.16017.

    I agree with what you say and I'm certainly one for applying Occam's Razor. The implications of these observations being the result of ET activity are huge and too far fetched for my liking. Even if I'm unable to find any reasonable explanation, I prefer to assume that there are terrestrial causes behind this, either natural or man-made.

    I should mention that I have heard of one other person from a nearby village who claims to have witnessed the same thing, though I have not personally spoken to this person about it. He is the brother of a friend of mine and he mentioned to my friend that he had witnessed very unusual 'moving lights' in the night sky at around the same date. He mentioned this months later without being aware of our observation, but it obviously rung a bell. He observed it from around 5 km east from where we did. I will ask him whether it appeared straight overhead or closer to the horizon, which might provide a basis on which to calculate distance and speed.

    Another curious thing I'd like to mention is that my neighbour made a short animation of our observation. In his animation the triangle formation is inverted, with one side facing forward rather than a vertice. The reason I first assumed it to be a military airplane is because the triangle formation reminded me of a delta wing seen in some military jets, with a vertice rather than a side facing the direction of motion. He also thought that the triangle contracted/reformed the same way it expanded, as if being rapidly stretched and shrunken. It shows how memory of such events can be quite different from one person to the next.
  17. Feb 9, 2015 #16


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    It is difficult to verify that, since without any reference points besides the objects themselves it is really difficult to tell if they have actually changed direction by that much or are just moving apart.
  18. Feb 14, 2015 #17
    True, in the end it's only my perception - what it appeared like to me. I know what I've seen, but there's no way I can verify or prove that this is what was actually going on. All I can do is compare what I've seen with previous experiences and with what others who were there witnessed. I can tell you, most people that I talk to are very sceptical and don't even take it seriously. (oh dude, but you had a few beers) It's very frustrating but also understandable. There's nothing else I can say other than what I've seen was unlike anything I've ever seen. Maybe there's a very banal explanation to it, but I just don't see it. I'll probably never know.
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