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A unidentified flying object is just that—a flying object that has not been identified. There need not be evidence of alien hi-jinx.

My criteria for a credible UFO report would include:

  • Verified by authentic photographic evidence or several eyewitness reports.
  • Insufficiently explained by natural or human-caused phenomena.
  • Furthermore, such an explanation must not be scientifically suspect, and also must be substantiated. There probably could be a reasonable explanation for all such events, but there must be some underlying evidence that the stated cause was, in fact, in effect at the time. For instance, if it is explained by some human-made aircraft, there must be evidence that such aircraft was flying in the vicinity of the sighting.

Of course, as reasoned skeptics, you are free to apply any criteria you deem relevant.

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I don't understand your third criterion. Why ask for evidence to identify flying objects when you're specifically looking for unidentified ones? –  David Thornley Mar 13 '11 at 0:35
@David: I was trying to exemplify some cases where an explanation could be suspect. At any rate, it seems I was a tad bit too specific. I'll try and find a middle ground for my next question. :-) –  Patches Mar 13 '11 at 1:26
What I would find more interesting, is how far you can forge a video evidence today. I've once seen some quite good quality footage... –  jokoon Mar 13 '11 at 1:33
@gokoon: I think that would make a rather interesting question. You should ask it! –  Patches Mar 13 '11 at 1:38
patches: haha, no you do it :p –  jokoon Mar 13 '11 at 13:10

3 Answers 3

up vote 21 down vote accepted

No UFO has ever been revealed to be an alien spacecraft. That said, we can't explain all UFOs through natural phenomena. In some cases the sightings remain mysterious.

From 1947 to 1969 a project called "Blue Book" was run by the USAF to investigate UFO sightings. The results are the following:

From 1947 to 1969, the Air Force investigated Unidentified Flying Objects under Project Blue Book. The project, headquartered at Wright-Patterson Air Force Base, Ohio, was terminated Dec. 17, 1969. Of a total of 12,618 sightings reported to Project Blue Book, 701 remained "unidentified."
-- source

As such, I would say that, yes, unidentified flying phenomena that cannot readily be explained away are quite common, 1 every 11 days on average (in the United States alone).

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++ It's really easy to generate UFOs. Just have something flying, and don't have enough money/time/interest to research it. I do sometimes enjoy watching History Channel shows where these people keep trying to sneak onto military bases, trying to expose what the government is hiding, which could, by implication, be alien spacecraft, else why would it be secret? –  Mike Dunlavey Mar 24 '11 at 20:50
Any UFO that is positively identified as an alien spacecraft would cease to be a UFO :) –  jwenting Apr 20 '11 at 8:26
Official FOIA source for the same document: archives.gov/foia/ufos.html (US National archives website) –  jwenting Apr 20 '11 at 9:15

As a military pilot, I have seen a few things in the sky that I was unsure as to what they were. There are many, many instances of unidentified objects being seen in the sky. Even as a subject matter expert on aircraft, there are other things that will be outside my area of expertise. Astronomical and meteorological phenomenon come to mind as the two most common outside of aircraft. That is to say, people are bound to see things in the sky that they don't recognize nor understand.

That of course is a long, long way to then declaring it some sort of extraterrestrial craft. I would say that in most instances, it's people seeing what they want to see, or just being too proud/stubborn to just admit they don't know, and glomming on to whatever idea they can think of.

If you look at the history of every single UFO sighting, the ones that are claimed to be aliens do not in any way manage to be convincing. The ones that are left as unexplained phenomenon usually end up having a perfectly natural experience.

By the way, here is my UFO story, and a caveat as to why an "expert witness" really is no better than any other witness:

As you know, I did submit a paper for presentation at the Sunday papers at TAM. Unfortunately I was not selected, but I promised to share my presentation with you. Since I was not selected, I didn't fully put the effort into the write up itself, but here is a basic outline of it. I did speak to Professor Hall (the curator of the papers), and hope that I can put together something for next year.

These words go along with this PowerPoint presentation: http://larianlequella.com/docs/Presentation.ppt

A while back, I gave a presentation at the second annual SkeptiCamp in Concord, New Hampshire. Granite State Skeptics, in particular Dale Roy, put this event together. It was great fun, and a lot of really terrific presentations were made. I got up there and did a presentation where I touted myself as a reliable witness, and then related a story that is quite representative of many other stories that we hear. Generally I tend to speak (and write) quite extemporaneously, so I will do my best to reproduce my talk here in written form.

So, the question is, if I related an extraordinary story to you, would you believe me? Let me start off a bit by bragging about myself. I want to really build the case that I am indeed a very reliable and trustworthy witness, and I should know what I saw better than most people.

First of all, I am a retired USAF officer. I served 20 years. I have a TS/SCI (Top Secret/Sensitive Compartmentalized Information) clearance. They don’t give those sort of clearances to just anyone. I even had an interim Yankee White clearance (for those that don’t know, that is a special clearance that they give to people supporting the President of the United States directly). These two levels of clearance are the highest levels of trust that the government will generally give an individual, and involve very thorough investigations into your trustworthiness and mental stability. In addition to these clearances, I also had what was called a Cogint Figure qualification. As a KC-135 refueling pilot, I would sometimes be called on to refuel Top Secret aircraft (so in addition to my clearances, I also saw airplanes others never did).

As I mentioned, I was a pilot. As a matter of fact, I was quite an accomplished pilot. I had an Instructor and Evaluator qualification in two USAF airframes (the highest level of qualification). In addition to the aircraft I primarily flew (the KC-135R and C-21A), I also flew the T-37, T-38, and various other general aviation aircraft. I have experienced most envelopes of human aviation. During my flying career, I flew all over the world. I have over 3000 hours in jet aircraft (more than many airline pilots even). And as a military pilot, I even got to do types of flying that non-military pilots could never imagine. Air refueling, which means I am flying in close formation with other aircraft and making them touch each other at 500 miles per hour, performing various types of rendezvous, flying on NVGs (Night Vision Goggles), and so forth. It is truly a unique way to fly!

As a pilot, we are expected to be familiar with all sorts of meteorology. We receive a practical and written exam on weather each year to maintain our qualifications. And every time we fly, we even get briefings on meteorology. Weather is a well known area for anyone who’s a professional pilot. Furthermore, I am an avid fan and hobbyist of astronomy. I took courses in both high school and college, and keep up with numerous journals and publications on astronomy, as well as physics. Yes, I am like Leonard on The Big Bang Theory! Although I went to Rensselaer Polytechnic Institute (RPI) and received my degree in Aeronautical Engineering (with specialized courses in hypersonic propulsion systems). I know quite a bit about science, technology, astronomy, and subject like that. Trust me, sit down with me for a while, buy me a beer, and I will talk your ear off on those subjects.

With these sort of credentials, I would think that if I relate a story to you, you would be inclined to take me at my word. I know what I am talking about, and I have the requisite subject matter expertise to be able to accurately identify anything I see out there. So what happened?

Well, I was doing a mission where we were flying from Egypt to Saudi Arabia. We had left Egypt at Oh Dark Thirty (very early in the morning), and were flying east. About half way to Saudi, we noticed that there was an aircraft about 45 miles ahead of us (we made this determination based on the apparent luminosity and size of the light we saw). Initially it was at the same altitude as we were, and it wasn’t moving in the windscreen (an indication that you are either on a collision course, or trailing them). After observing it for a short while, we noticed that we had no closure on it, so we figured we were indeed trailing them. Of course, just to be safe, we tried to paint the aircraft with our radar. Well, it never showed up on the radar at all. As we are puzzling over the fact that it is clearly within range of our radar but we couldn’t paint it (45 miles was our determination based on a large aircraft with that luminosity, a smaller aircraft would have been even closer and easier to paint with our radar), we also noticed that the aircraft was climbing. Now we were cruising at about Mach 0.83, at an altitude of FL390. For an aircraft to maintain the same distance (and from the apparent luminosity it even seemed to be pulling away), and also climb was pretty unusual. Of course, throughout this whole time, it just seemed that AWACs (our air traffic control) was unusually silent. They really weren’t talking to a lot of people. Again we re-checked our traffic, and now we saw that they were just incredibly high in the sky. Using some simple trigonometry (who ever said you’d never need it after school?) we calculated that the unknown aircraft was at an altitude of FL800! The only airplanes that operate at those altitudes are either supersonic, rocket powered, or had no business being in the Middle East. What we were watching did not confirm to the performance characteristics of any know aircraft. And it just kept climbing!

So what was it? Would you believed me if I had claimed that based on what I know about a myriad of subjects, and my level of technical expertise and knowledge, that I could eliminate any technology possessed by mankind. And it was clearly an artificial object in the sky. Thus by process of elimination that it was an artificial object that couldn’t have been made by mankind, it therefore must have been a UFO? After all, my story appears very similar to a myriad of other such stories told. After all, I am a reliable witness, right?

Okay, I’ll fess up. I was actually looking at Venus! Yep, the best excuse for the Men in Black! So, why would someone who has such an extensive data-set of information and knowledge at his disposal make such a classic mistake? To put it bluntly, it’s because our brains suck!

Maybe you want a few more details than just that? Okay, there are many factors at play here, and hopefully I can articulate them all for you. First of all, when you are flying and looking out the front window, the thing you are looking for, and expect to see are other airplanes. They are the “threat” out there, and it is your default position. You have an expectation to see something, and you generally know what to look for. Even at 45 miles away, if you were heading straight at each other at jet speeds, you would only have a couple of minutes of useful time to make a determination of danger. Also, our brains evolved on the plains of Africa. The environment we are suited to is having our eyes about 5 feet off the ground, and moving at a speed of about 2 miles per hour. Given our technology, we are quite often outside that performance envelope. Also, our brains will try to make sense of the visual input we get, and will assign references to it, even if they aren’t there. In this particular case, we all know Venus can be quite bright. However, we can’t really judge distances at night, especially when there are no other features to compare it to. So in this particular case, my brain, as well as the brain of the rest of the crew, all saw something with an expected luminosity of a large aircraft, and assigned a value of 45 miles to it. We are generally experts at that sort of determination, but in this particular case, since it wasn’t actually an aircraft, we got it quite wrong. There are many, many other factors at play with our brains in this story, and I only covered the very few basics of them. For instance, there is a well known phenomenon where you can focus on one thing so hard, that you don’t notice other more startling or shocking things. If anyone is not familiar with the video where you need to count the number of times a team with white shirts pass a basketball back and forth (while there is also a team with black shirts doing the same thing), I recommend you have someone find it for you (By the way, I think I got the correct number of passes in that test!). Also, as soon as our brain receives data that it can’t quite make sense of, it will attempt to force that data to make sense. That is why “eyewitness” reports are generally not that good. We actually are horrible observers of the world around us, and we are constantly filling in details and just plain letting our brains make stuff up for us.

So you see, our brains do suck in many ways (and of course, it’s still quite good in many other ways). The cautionary tale here is not that you should throw out all eyewitness reports of everything. Just take it with a grain of salt, and of course question the conclusions that the eyewitness made based on what they saw. Thankfully for me, we did finally figure out what it was that we were looking at, and our crew managed to avoid embarrassment had we filled out a SAFIRE report. It is interesting that we did discount our instruments (radar, TCAS, etc.) that told us that there wasn’t an object at 45 miles away. Again, we were fixated on it (see the story of Eastern Air Lines Flight 401 for a perfect example of fixation), and because it could have been a threat to us, the lizard part of our brains took over and drove our perceptions from that point on. It took us consciously telling our brains to shut up and allow other data to influence us before we were able to correct our mistake. And of course, being willing to accept that fact that such highly trained and smart people like us could make a mistake also played into us discovering that we were indeed mistaken.

If anyone has any other questions, or wants to talk more about this (or any other skeptical subject), I can be reached at Larian@LarianLeQuella.com or you can find me stalking the web at places like JREF, Bad Astronomy, Skeptics StackExchange, and of course Facebook.

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++ My cousin was a Navy pilot, and now flies corporate jets. Same idea. It's still hard to explain the concept that absence of evidence is not evidence. –  Mike Dunlavey Mar 24 '11 at 20:43
Oooo... anecdotal answer by a moderator? =8^) –  Sklivvz Jul 6 '12 at 16:30
@Sklivvz hehe, I got busted. Of course, Patches is asking for something that doesn't exist, so how do you cite that? –  Larian LeQuella Jul 7 '12 at 1:32
Is there a decimal point missing somewhere? To close 45 miles in 12 seconds is 3.75 miles/sec, 6km/s, or about Mach 17. That seems a bit fast for two aircraft on a collision course. Or maybe there's something about your "airplane" that allows it to go that fast that you haven't told us :-) –  Paul May 14 at 5:36
Don't sweat it. If the men in black didn't find out about that Mach 17 joy ride back then, you are probably OK. :-) –  Paul May 15 at 7:18

They are not flying and they are not objects.
But people saw them :)
(you can find a colection of reports of events in my site)

The events are more correctly called: UAP - Unidentified Aerial Phenomenon.

Because I've been always skeptic I studied this subject several years ago (during months),
and I concluded that two classes of UFO events can be physically explained. (edit add: I decided to offline the content because no one care to know what I found)
IMO they are just Aerial Phenomenons. If you are so skeptic as I am you will have to study what I've explained there.
I'm expecting some comments if you deny my view point and downvote.
(the physical papers that I've consulted in relation to ice crystals and contrails... will be included in the site in the future)

quote from "Pilot Survey Results” at NARCAP.ORG (the site is offline in the moment of writing)

This paper presents the results of a confidential aircrew survey presented to 298 currently rated and flying commercial pilots employed by a U. S. airline. Table 5

Results Related to Reporting One’s Sighting

Total number of pilots having seen a UAP . .. . 16 (100%)
Number who did report the sighting . . . . . . . . 4 (25 %)
Number who did not report the sighting . . . . . 12 (75 %)

If there are about 600,000 commercial pilots currently flying in the U.S.A. and 23 percent of them saw something they couldn’t identify this amounts to 138,000 witnesses.

colections of reports on UFOs:
COMETA report (French association) detail the results of a study by the Institute of Higher Studies for National Defense
COMETA_part1.pdf 23 pages
COMETA_part2.pdf 47 pages

UK gov. National Arquives, UFO files Files released in March 2011
NASA ASRS Database world's largest repository of voluntary, confidential safety information provided by aviation's frontline personnel, including pilots.
National Aviation Reporting Center on Anomalous Phenomena- NARCAP
Narcap: 300 cases analysed

a few selected cases:
Chicago O'Hare airport: Narcap report
Astronautics & Aeronautics July 1971 Unidentified Object in the ~South-Central U.S., July 17,1957
L'observation du vol AF 3532 1994, Coulommiers, France (more here)
Analysis of a Photograph of a High Speed Ball of Light Jul 16, 1988 - I clearly see a contrail where sunlight is reflected.
google search "Police Chase UFO over St. Atham, Cardiff", in UK 2008

The Scientists have been divorced of the UFO problem:
Society for Scientific Exploration: Report on a Survey of the Membership of the American Astronomical Society Concerning the UFO Problem: (1994) : Part 1 and Part 2

My viewpoint of the case reported by a military pilot in the page 9 of Cometa report (pag 7 of pdf), Mirage IV - UFO encounter, March 7, 1977:
Chaumont 48° 6'40.76"N , 5° 8'23.67"E
Luxeil Air Base 47°46'59.00"N ; 6°21'1.29"E

Not reported, but it is true:
No one noticed that the path of flight was in the directon of the Full Moon, South India, and the contrail was above Switzerland (cold atmosphere, no wind for sure at the time of the event). The contrail stood straight for long enough time and transported the light of Full Moon, below the horizon, to the cockpit.
Just check the images bellow, obtained with help of HPlanet - Home Planet software and Google Maps)

Physical explanation:
A contrail is made of ice crystals that in non turbulent atmosphere descend slowly exposing the bigger faces (frequently hexagonal) parallel to the ground (they go down like a large leave falling from a tree). The normal to that face oscilates around 8º max and they offer a continuous mirror for light that jump from crystal to crystal without leaving the contrail when light is injected along the longitudinal axis of the contrail. The total reflection in the faces are due to the low angle of incidence providing a 'natural low loss optical fiber'. And that was the case of this report. The pilots usually can not see the contrails made by their own jets. This case is an exception. The contrail was there in the right direction and the moon light (full moon) made the impossible: for brief moments the pilots saw the moon. Most of the UFO lights seen by night are made by some invisible contrail in the right direction to sunlight or, the less frequent moonlight, when the sun or moon are already below the horizon.

Position of full moon over South India at the time of the event. position of full moon over South India

Local path of the flight over France and Switzerland local path of the flight

At left two red points (zoom it) is the path of the Mirage over France/Switzerland and a large white stripe to mark the path of the moon ligth. at left (red points) the path of the Mirage over France/Switzerland and a large white stripe to mark the path of the moon ligth

Check the report of the pilot:

They noticed a brilliant light coming towards their Mirage from their exact right and on a collision course with them, and first thought it may be a jet fighter, but when they radioed to the ground control at Contrex?ville for reporting it and getting it identified, they learned that the ground radar showed nothing and that no other aircraft was known to be in that area. The ground controller asked them to check their oxygen, which indicates that he thought the pilots may be hallucinating.

The light appeared bigger and bigger as it approached their aircraft from their rear right. The pilot was flying at Mach 0.98 and made a turn to the right and then to the left to make sure the light was not a reflection of some sort on the cockpit. As he did these maneuvers, both of the crew could distinguish that the light was the front of a dark solid object. Despite the evasive maneuver, the unidentified object managed to stay exactly behind them for a few seconds, a very dangerous situation if the unknown object were to be hostile. The then object made a turn to the North-West at an estimated speed of Mach II, and went away to the left of the Mirage IV.

and reappeared 45 secs later to tease again the pilots.

In my oppinion this report of the pilots is credible. Also credible is the existence of the contrails, even if we can not see them by night time. Incredible, IMO, is the lack of imagination of the scientific community and others, that in the absence of a theory try to put down the testimonys, or waiting for help from some alien people.

By day time the testimonys are mostly correct but the physical explanation is based in the well known (in this moment I dont have the name in my head)... effect, and ....

They report 'objects' but they saw 'light'.
Find a suitable source of Light and a path thru the medium (atmosphere).

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Let me know if you can not see the images I've included, because the computer I'm using has stored all passwords and I may be fooled. –  Helder Velez Mar 25 '11 at 15:57
the images load after you click some links –  Jader Dias Apr 14 '11 at 19:27
@Jader Thanks. (Now I've updated the answwr to other link more actualized). As I'm not a natural english speaker I do not know if I said my ideas clearly in physical and english terms. Tanks for your feedback. –  Helder Velez Apr 20 '11 at 3:32
it's spelled "thanks" =) –  Jader Dias Apr 20 '11 at 11:19
I was still awake at five o'clock in the morning and mistakes happen. I'm Portuguese and I think you are Brazilian and lives in Brazil given the timing of your comments. But what I like to know is whether it is easy to understand what I try to explain in my link. Obrigado. –  Helder Velez Apr 20 '11 at 11:44

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