How good are we at estimating the distance and altitude of UFOs?

One of the most frequent aspects that I often see people describe in UFO reports, is how far away or how high above the ground the UFO seemed to be. This is a feature of UFO reports that has long being playing on my mind, and I have finally decided to make a post about it since I have never seen this subject formally tackled on here, and I think it deserves it's own thread since it potentially has implications for a large percentage of UFO reports.

Whilst it's relatively easy to estimate distances relatively accurately under "normal" circumstances, normal circumstances being familiar objects observed in daylight (or indoors) on the ground or below the horizon, accurately judging the distance (and therefore altitude) of an object/light of unknown size/brightness that is seen in the sky is virtually impossible to do.

Why?

Well for starters, it's an unknown object. If you don't know what an object is, how can you have any idea what size the object is?

How do we (or "our brains" if you like) estimate the size of something under normal circumstances? The answer is actually quite complex.

Firstly, our brains have past experience which is referred to and used as a guide when we estimate the size of known objects. As well as this, our brain relies on certain "cues" such as whether or not the object in question is behind or in front of other objects, which gives us distance cues that help us to estimate the size of something. Shadows and shading are also an example of cues which help our brains work out the position (and therefore distance) of an object in a scene.

If those cues are taken away, as they often are with objects/lights seen in the sky, at distance and especially at night, it becomes much more difficult for us (our brains) to make sense of what we are seeing. Not only is it possible, but it is inevitable that our brains will attempt (badly) to fill in the gaps left by the missing cues.

Since we have evolved with our brains to operate in daylight, the assumptions that our brains make, which would usually work well under those circumstances, are now completely useless. In evolutionary terms it doesn't matter much since there is no survival benefit to being able to judge the size and distance of a distant object in the sky - all our predators in our evolutionary past have been land based.

Take for example a lone light in the sky at night. Without any other cues, our brains only have brightness as a clue to how large or far the light is. Our brains have to make an assumption based on this one cue, and since on the ground, under "normal circumstances" bright lights tend to be closer than dim lights, the brain interprets a bright light in the sky as being much closer than it actually is!

The technical term for this is an optical illusion, and despite many people assuming (wrongly) that they are immune, there are actually only a very small percentage of people that are immune to certain optical illusions (but not all).

In fact it's quite easy to confuse the brain even at short distance in broad daylight with just a little bit of cue manipulation, let alone at night and at distance with an unknown object/objects/light/lights. Watch this clip taken from a BBC Horizon documentary. It's worth tracking down and watching the whole program if you can.




Couple this with the fact that people in general are not too familiar with the night sky (although most here would probably say they are, but there is "familiar" and "familiar", and in my experience there are wide gaps in most peoples experience of the night sky, which is not surprising since most people don't spend many hours observing, and when they do, there is usually so much light pollution that they do not see much), and specifically how bright some objects can appear to be, and you have a recipe for a UFO sighting where likely possible causes are ruled out on the basis that "it was too close to be this" or, "I have seen those before and it didn't look like that".

Meteors

As some of you out there will know, I am a keen observer of meteors, and it was this subject that initially sparked my interest into what we are seeing when we see a meteor. It's no coincidence that they can easily fool people's brains into believing that they might not be seeing a meteor, partly because how bright a meteor can be, which takes many by surprise in my experience.

It's actually quite common to get reports of UFOs at the same time as a bright meteor is spotted widely by lots of people, and there is no doubt that what people are reporting as a "UFO" was in fact a misidentified meteor, as the described characteristics match almost exactly that of the meteor seen by lots of other people at the same time.

Even more commonly the meteor is misidentified as a plane or aircraft engulfed in flames (suggesting it seemed to be relatively close), or the report goes along the lines of "I saw it fall just over the next hill", and we know that this is not the case as other people 10's of km say the exact same thing. In some cases when the fallen meteorite/s is/are recovered, it always turns out that in the area in which the meteorites were discovered, people report seeing the meteor terminate almost directly overhead!

One thing in particular that compounds the situation with meteors, is that many people (sometimes even experienced astronomers) are unaware how different the characteristics of meteors can be. Many have a distinct mental picture of what a meteor should look like according to the few meteors that they may have seen in the past.

Experienced meteor observers on the other hand know that although most meteors are a bit plain, and like your "average shooting-star", if you are patient and spend a bit of time observing, you will start to see meteors that appear to be strikingly different to that "average shooting-star". It's one of those things that has to be seen with your own eyes for you to have a good idea of what I am talking about.

Those of you out there that have, will know what I'm talking about, but anybody can go out and prove this for themselves, if they want to and they have the patience, and I highly recommend trying it, but do read up on how to observe properly, and just as importantly when. I won't go into to much detail here as I don't want to go too far off topic here, but go here or U2U me if you want some basic info/links to get started.


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Here is one example of a recent bright meteor that was reported by quite a few people in Queensland, Australia. I've singled out a few conflicting reports.

(Observer A)
Ripley, Ipswich, Queensland 7:50 pm 20NOV2011
My name is John and I live in Ripley, Ipswich, Queensland. I just happened to be looking towards the South West when I saw a slow moving Metorite heading North East. As it passed though the trees I had an awesome view of it and would of been at around 2-4,000ft above the ground.
It had a blue and green glow to it and because it was so close to me you could see the could see red and orange sparks in the tail. When glow went away you could still see red and orange sparks come from it. To cage how close it was to me I live about 12klms (approx) from Amberly Airforce Base which is West North West of my poistion and it looked as if it flew over the top of it and out the point of burn out, it still sparked Red and Orange at what looked like 1,500ft. Awesome sight to see. regards, John Stewart Thank you John!

(Observer B)
Canungra, Queensland, Australia Meteor 7:35 pm 20NOV2011
We saw a huge meteor in the sky tonight at 7.35pm. We had just left Canungra (a town inland from the Gold Coast) and saw it in the sky towards the west - it was travelling north. It was VERY large and close - it continued for about 5-10 seconds. At first we thought it was a plane on fire but it burnt up in the sky so must have been a meteor. It was a bright white light with 2 seperate white heads merging into a single tail which was more orange. Cheers - Donna Thank you Donna!

(Observer C)
Redcliffe, Qld, Australia ~8:00 pm 20NOV2011
We saw a large bright white round shape with a tail move north low in the western sky. We watched for 2 - 3 seconds. Approx 8pm on 20 Nov 2011 from Redcliffe, Qld, Australia
Megan Stuart

Source: lunarmeteoritehunters



I've marked the locations of all three reports on the map above.

Both observers A and B reported it as being very "close", but they are around 50 miles apart. Observer A reports the meteor as seeming to end at around 12 km NW of his location, so it could not have been close to observer B at all.

Observer C's report also clashes with the other reports, and if you go through more reports of meteors, the same pattern emerges.

Now meteors are just one particular example, but the same thing can apply to virtually any light/object seen in the sky and/or at night, and there are lots of them, including satellites, aircraft, stars, planets, and even the moon.

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The Moon Illusion

In fact the moon is well known to play tricks on the eyes, and the so called "Moon illusion" is just one aspect that has been widely discussed and studied in scientific circles. The way the illusion works shares many similarities with other illusions like the ones a person would observe with seeing an unknown light in the sky, so I think it's a great example that shows just how much our mind can distort reality, even where relatively familiar objects are concerned.

This page sums up our current understanding of the science behind the illusion. For those who are too lazy to look, I've taken a few relevant paragraphs and pasted them below.

Explanations of illusions must be taken with appropriate skepticism. Many are of the nature of "plausible hypotheses." Most are not (as yet) such that they can be independently verified in terms of physical processes in the brain. Also, we know that our visual perceptions arise because our brain synthesizes multiple cues. Our brain weighs these cues; some dominate in certain conditions, while others are "weaker" and are ignored. But the weightings shift in strength according to the nature of the stimuli. Many classic visual illusions arise from conflicting sensory cues of nearly equal "strength".

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When we judge the size of an object near the horizon our perception is influenced by familiar terrestrial objects in the field of view (trees, houses, roads). We know from everyday experience that many of the recognizable things we see in the distance are quite far away. But when our gaze is upwards, we have no reference cues for distance, and judge things near the zenith to be closer than those on the horizon.

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Perceptions are influenced by our past experience. One model of visual perception postulates that when we perceive a new and unfamiliar phenomenon our brain interprets it by comparing it to a mental map or model of our memory of previous sensory experiences. Of course, this represents just one of the cues that the brain must sort out, weighing it against other cues. Conflict between sensory cues is the basis of many common visual illusions.

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This is the same as saying, "What is our judgment of actual size of two things at different perceived distances, even though they have the same angular size?" The answer is that the one assumed nearer is judged to be smaller. This conclusion is consistent with the mental judgment that the horizon moon is farther from us.

This process supposedly operates even (especially) in the absence of any other visual cues. But the process is confused when we have our heads in an unusual position. This may be the result of our knowledge of the orientation of our head, from visual cues, and perhaps from information from the balance-sensing mechanisms of our inner ear. When there are competing sensory cues, our judgment of angular size can be altered by them, which may account for the confusing results of experiments designed to show that visual cues are the sole reason for the moon effect.

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The hard-wired hypothesis supposes that natural selection has shaped those brain mechanisms that process and interpret sensory data, devoting more resources to those things that are important to survival. This results in brain resources being biased toward things seen in front of us, fewer resources to things overhead. Similar imbalance of perception details are present in animals.

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How does this impression square with the situation in real (physical) space? The physical distance to the most distant object one can see on the horizon depends on the elevation of the observer's eye above the water. One can derive the formula for it, in terms of the earth's radius. For an eye elevation of six feet, the things we see on the horizon are actually about 3 miles away. Alto-cumulous clouds are about 2 to 3.5 miles overhead. So, physically, the distances are nearly the same, yet the overhead clouds seem much closer to most people than those near the horizon. This calculation may not seem quite fair, for we can see clouds that are physically well beyond the surface horizon, perhaps 10 miles away, due to their height above the earth surface. But can any reader and observer honestly claim that the clouds at the horizon seem farther away than the horizon? I've never found anyone who would make that claim.

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We have a strong impression that the cloud cover "joins" the horizon. Can this simply be that there's absolutely no visual cue to suggest that they are at different distances? Our brain may be making the simplest reconciliation of the situation.

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Continued from the previous post.

The moon illusion is consistent with what would be expected from evolutionary considerations. We have evolved cognitive processes that provide high quality visual information from nearby things, and things on our level that we can walk to and experience from various angles. These are all important to survival. Things seen high above, in the sky, or even those seen below, as when looking over the edge of a cliff, are less important. Therefore distance discrimination and detailed judgment of other visual properties of overhead objects is compromised.

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In these discussions we must distinguish three levels of sensory processing that play a role in the final judgment.

1. The sensation itself. In this case, the diameter of the image on the retina, stimulating light receptors there. All researchers agree that the moon illusion does not occur on this level.

2. The unconscious judgment of some "physical" property, such as brightness, angular size, color. This may be influenced by past experience, or by quirks of innate cognitive functioning, but is done without us consciously "thinking about the matter" or deliberately "analyzing" something.

3. The reasoned consideration of the sensation, by questioning and by conscious analysis. Example: "Those two bars seem connected, but that can't be so, for it violates some laws of math or physics." On this level, judgments may be expected to be quite different for untrained and trained observers, and also different for those unschooled in math and physics compared to those who are. The moon illusion literature is largely silent on these possible differences of interpretation.

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Observers schooled in physics and math, physicists, astronomers, and amateur sky-gazers, have learned somewhat different conscious models. When asked "Which moon is nearer?" they may respond "That's an unfair question; it's still the same moon, and in both cases the distance and size are too great to make a distance judgment." If a follow-up question is asked, "Which one seems nearer?" the answer is often "Well, you can't trust your eyes in such matters." Many scientists have learned (by their mistakes) not to trust their eyes in certain kinds of informal observations. As Helmholtz said, "I would never believe anything solely on the evidence of my eyes." Unlike Helmholtz, most physical scientists do not inquire into the reasons behind visual deceptions, they simply try to stick to observations and instruments that can be shown to produce reliable and observer-independent results.

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All real-sky effects are beyond the range where our stereoscopic vision (due to eye convergence) works (up to about 50 to 100 feet), so our eyes can't triangulate objects in the sky.

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Pilots and Aviation

Astronomers and psychologists are not the only groups of people who realize that judging distance, size, and altitude especially at night is notoriously risky. The aviation industry for obvious reasons has been well aware of this for a long time. The following has been taken from an on-line flight training manual that I found.

Night Sight Skills

The ability to judge distances and heights at night is difficult at night. The absence of haze or its presence can cause illusions at night. Lights will vary in intensity and cause illusion effects. A misidentified light source can cause total confusion. A single light gives no altitude information. Multiple lights may be in different geometric visual planes. Freeways become visible while country roads disappear. Aircraft and lighted towers become visible for miles. Airports have beacons. The most common illusion is a narrow runway that appears to be longer than it is. the narrow runway may make you think that you are too high. Have a set procedure; allow an extra wide downwind at night. Know the length of your destination runway. Required FAR knowledge on all flights! All illusions are made worse at night.


Lights that appear dim, as seen through haze, will be reported as more distant than they are.


The dearth of visual cues is what makes night flying different and more dangerous.

Source: pilotfriend.com

Summing up

I'm not saying that this explains all UFO sightings, but from the evidence I have seen (some of which I have presented in this thread), and from what I have read over the years on this forum, it seems that in many cases people who have seen something relatively mundane will not recognize or be able to identify what they saw in many cases, because their brain is literally feeding them false information.

Many of these cases are further compounded because people have preconceived ideas about what something should look like. That is human nature I guess, but I find it hard to understand why this fact is so often overlooked by the UFO community in general. Are we not supposed to be "denying ignorance" here?

Is it really that hard to accept that we as humans have certain limitations when it comes to observing/witnessing certain events, and that large numbers of people misidentify relatively common phenomena on a regular basis?

I have only just scratched the surface of this subject, but I hope that what I have written here may help others out there to understand a bit more about what they have seen, and how our perception makes things a bit more complicated than they may at first seem in some cases.

reply to post by C.H.U.D.


i would say not very good unless it is something we are familar with. if i see a plane i can usually tell how far away it is because i am familiar with it's shape and how big it is on the ground level, therefore are able to judge better how far away it is depending on its size in the sky.

however if i think back to my only u.f.o. experience, the shape was not familar and although i was certain it was nothing i had seen before or ever again, when i first obseved it i was not sure if it was huge and far away or small and close. therefore it could of been the size of a car or the size of 3 football pitches for all i knew.

it was only toward the end of the sighting that it passed infront of a small cloud, but even then all i could tell was it was above whatever the cloud level was.

so i would say pretty useless unless it is something we are familar with like a hot air balloon, or it passes something that gives a reference (for example going through clouds) but if it is unfamilar that can only give a limited idea.

reply to post by C.H.U.D.

Good effort for your thread. I seen one once. I was on a ridge line overlooking a valley at night and the thingy I saw was at eye level bisecting the valley down the entire length of it. The sighting lasted long enough for me to determine that it was going like a bat outta hell, making the other aircraft in the sky look like they were standing still. It was totally silent and looked quite different from any craft I have ever seen. There was no doubt I was seeing something technological, and not from this world. I couldn't tell you how fast it was going, just impossibly fast. I couldn't tell you how big it was, maybe bigger than a fighter jet and smaller than a small airliner.

I know seeing is deceiving. Take this video for instance. Yes it's just another YouTube video I have no chain of custody for. But if it is real, tell me how big these are, how fast they are moving and how quick they exit the earths atmosphere? Anybodies guess because we have no frame of reference for either the objects or their maneuvers...

reply to post by C.H.U.D.
Nicely written thread

I'm not saying that this explains all UFO sightings, but from the evidence I have seen (some of which I have presented in this thread), and from what I have read over the years on this forum, it seems that in many cases people who have seen something relatively mundane will not recognize or be able to identify what they saw in many cases, because their brain is literally feeding them false information.

As well as our brains misunderstanding what we see, the knowledge we have informs how we express, or share, what we thought we saw. You're a good example of this in the sense that you are more informed about meteors and would have a higher degree of accuracy in identifying a moving light as 'meteor.' With your background, you'd also be better able to express what you thought you saw.

Of course, this would also add an element of observer bias in your own brain as it sought to pin the *meteor* label on moving objects that didn't have FAA lights. The same, broad effect is what we see when so many people pin the *UFO as spacecraft* tag on fast-moving lights. Their knowledge of aviation and meteorology is less than their knowledge of UFOs and You Tube and the brain spits out the answer >>> UFO as spaceship.

Is it really that hard to accept that we as humans have certain limitations when it comes to observing/witnessing certain events, and that large numbers of people misidentify relatively common phenomena on a regular basis?

It's a fair position to take although *mission creep* shouldn't be encouraged in those who misuse those 'limitations' as a tool to dismiss every witness account.

I've starred your posts and flagged for adding a thread that took effort to write and folk should find interesting.

Another classic perception problem, as illustrated in the OP's meteor quotes from Australia, is due to people mistaking 'bright' for 'large'. It's well known that many unfamiliar with the night sky will describe brighter stars as larger, when in fact they are the all point light sources.

How many ufo reports describe a huge light in the sky? An awful lot!

Heck people, including the news media cannot tell the difference between a rocket and an airplane contrail at sunset..

People look at a rocket launch and think it is falling

People look at a stage separation and think its a UFO that destroyed a missile

People see an airplane heading towards the camera and swear it is a rocket going up

There is no way... without a reference point that anyone can judge speed, distance or size

especially of the glowing shape shifting critters

Originally posted by zorgon
especially of the glowing shape shifting critters

what about other influencing factors....

Originally posted by Kandinsky
Of course, this would also add an element of observer bias in your own brain as it sought to pin the *meteor* label on moving objects that didn't have FAA lights. The same, broad effect is what we see when so many people pin the *UFO as spacecraft* tag on fast-moving lights. Their knowledge of aviation and meteorology is less than their knowledge of UFOs and You Tube and the brain spits out the answer >>> UFO as spaceship.

but how does any knowledge help in getting around an inductive bias?

Is it realy close or is it realy big?
Its not complicated until the eye play tricks on you.
Actualy, i've learned alot from the Montreal UFO of 1990, nov.7, between 7pm and 10pm.

I still struggle with estimating cloud layer elevation, let alone UFOs, and I've been flying helicopters for 10 years!

Havent read the post yet but would like to point out that we used to have observers in WW2 were quite easily capable of identifying types of aircraft, distance and direction with very little training.

The average person (this includes me i admit) is HARDLY able to properly guess flight heights, speeds, distances and sizes of some "light" in the sky.

It's a given that the majority of what people are porting in "UFO reports" are pure nonsense numbers, the fact not even considerated that MANY people who report UFOs have a very low level of education. (I am not saying this to insult, it's simply a fact)

MANY have no clue about meteorologic phenomena, air craft, astronomy etc and show a horrible lack of common sense. And then those same people give numbers like how fast an object was moving or how high it was etc...which makes many (not all!) such reports rather worthless.

Originally posted by flexy123
The average person (this includes me i admit) is HARDLY able to properly guess flight heights, speeds, distances and sizes of some "light" in the sky.

www.vendian.org...

S&F

One of the best threads ive seen in this forum for a long time.

reply to post by C.H.U.D.

Excellent thread C.H.U.D.!

It is defintely true that most witness estimates of the size, speed and distance/altitude of an unknown object in the sky have little value when stated as such.

A skilled investigator may be able to extract additional details from the witness with a skilled line of questioning. This may involve going back to the location of the sighting, looking for landmarks, and then determining the angular distance traveled between those landmarks in a given estimated period of time. However not knowing the distance to the object, it's still impossible to determine velocity with any certainty, though the possibility of common objects like meteors and satellites might be evaluated better in this perspective.

Here is an example of a "UFO" that some witnesses reported as being over 100 meters in length and as you can see its not much over 1 meter long:

[atsimg]http://files.abovetopsecret.com/images/member/b6a609094dac.jpg[/atsimg]
"Linn Murphy UFO"

At 400 feet altitude, the UFO (which weighs about a pound) looks like a mammoth spacecraft miles away, dancing, diving, hovering, now flitting away.

Obviously the witnesses had no idea what it was, assumed it was distant and huge, when it fact it was much closer than they thought.

The moon illusion baffles me to this day, I've read everything I can about it but I find it annoying to be so easily deceived by my own eyes.

Investigating the Kecksburg UFO really opened my eyes to the variation in distance reports of a meteor by people across multiple states; the estimates were all over the place, like the example you showed in your op.

reply to post by Arbitrageur

Investigating the Kecksburg UFO really opened my eyes to the variation in distance reports of a meteor by people across multiple states; the estimates were all over the place, like the example you showed in your op.

Not just estimates of size and distance were out. If you look at the reported times of the meteor sightings, they demonstrate no consensus. 13 reports and of those in the AEST time-zone, a variation of 1 hour and 10 minutes.

Out of curiosity, I've made a very brief attempt to see if any UFO reports were made on the same evening and haven't found any. It would have been interesting to see who offered the more accurate sighting report?

It's perhaps ironic that, if this was a UFO report, a determined UFO 'debunker' would use the differences in timings to dismiss the 13+ witnesses as unreliable and possibly hoaxers of poor character. As this isn't a UFO incident (in the conventional sense), we are able to take the position that the witnesses did see a flaming meteor and reported the details accurately...despite the differences in time.