Chapter 2

Processes of Perception, Conception, and Reporting

William K. Hartmann

1. Introduction
2. Perception: Objects and Phenomena in the Atmosphere
3. Conception : The Re-entry of Zond IV Debris
4. Conception: Re-entry of Titan 3 C-4 Debris
5. Conception: The Great Fireball of 9 February 1913
6. Additional Remarks on Percepts and Concepts
7. Reporting
8. Reports: The Credible Number of "Flying Saucers"
9. Conclusions
BACK to Contents

1. Introduction

The preceding chapter outlined the sequence of events, physical, physiological, and psychological, by which perception of a phenomenon is combined with previous conceptions. In this chapter we will review some evidence on how this proceeds in fact, and on how the conceptions, sometimes after significant interpretation, produce a report.

The question underlying this discussion is this: Are misinterpretation and misreporting sufficiently common as to make credible the assertion that the entire UFO phenomenon, or at least the residual of unidentified cases, is the result of these processes (plus deliberate hoaxes)? The data show that this assertion is indeed credible, although, of course, we cannot prove that this accounts for the unidentified objects.


2. Perception: Objects and Phenomena in the Atmosphere

In practice, it has proven impossible and potentially misleading to try to tabulate all of the possible causes of UFO perception. There are simply too many. The very point that is emphasized by case after case is the incredible variety of circumstances that may cause one to perceive an apparition of high strangeness and conceive of it as an UFO, or even more specifically as a "flying saucer."

Minnaert (1954), Menzel (1953), and Menzel and Boyd (1963) have described in detail many objects and phenomena that are unfamiliar to most persons. We need not repeat their description here. However, simply to illustrate the variety of causes that can and have produced UFO reports, Table 1 briefly lists some of the possibilities.

We can be virtually certain that all of the causes in Table 1 have, at one time or another, produced perceptions that could not be identified by the observer. It is perhaps not surprising, therefore, that about 3,000,000 out of 125,000,000 adult civilian Americans have perceived


Table 1

Examples of UFO-Related Objects and Phenomena

Subsun Gulfstream aircraft (Case 54)
Lenticular clouds Cf. Section III, Chapter 3
Noctilucent clouds "Glowing" clouds, often in peculiar shapes
Mirages Examples cited by Menzel (1953), Menzel and Boyd (1963)
Sundog "Dust devils", etc. Debris thrown into air without apparent support.
St. Elmo's fire Cf. Section VI, Chapter 7
Ball lightning  

Meteors, fireballs Cf. discussion of 1913 fireball, this chapter
Satellite reentries Cf. discussion of Zond IV, this chapter
Venus, other planets  

"Skyhook" balloons Responsible for Mantell tragedy (Menzel and Boyd, 1963)
Other balloons, Test aircraft Certain, little-flown types have been disk-shaped
Rocket launches Rockets and contrails have generated UFO reports
High-alt. Projectiles Have been used in flare and wind-study experiments (Cf. New Mexico aircraft (Case 55)
Bomb tests, Contrails Fort Belvoir, Va. (Case 50)
Refueling Searchlight reflections Coarsegold, Calif. (Case 28)


Table 1 (cont'd)

Aircraft reflections Great Falls, Mont. (Case 47)
Aircraft afterburner  
Aircraft seen at unusual angles  
Aircraft landing lights  
Flare experiments  

Autokinesis Perceived motion of objects known to be stationary
"Autostasis" Perceived stopping of objects known to be moving
Entoptic effects Generated within the eyeball
Motes on the cornea Perceived as spots
"Airship effect" Perceived connection of separate sources (cf. this chapter)
"Excitedness effect" Selection effect on reports (cf. this chapter)

Detergent foam  

Angel hair  
Airborn debris (e.g. milkweed) Camarillo, Calif. (Case 58)
Birds, flocks of birds Tremonton, Utah (Case 49)
Swarms of insects  
Luminous fungi on birds  


Table 1 (cont'd)

Hot-air balloons UFO reports generated by toy balloons using candles to create hot air (Boulder, Colo., Case 18 )
Reflections off windows Witness interprets reflection as object outside window
Material fixed or moving on Window As above
Deliberate hoaxes  


phenomena that they classify as "Unidentified Flying Objects" (See Section III, Chapter 8). The question is whether a few of these reports are extraordinary.

Table 1 raises a problem for the UFO investigator: in a given case, how unusual may a phenomenon be to be cited as explanation? Certain investigators have been widely criticized for constructing elaborate conditions to explain (or explain away) UFO reports. One should be guided by "Occam's Razor": an explanation becomes less credible as the number of ad hoc assumptions increases. Table 1 is not a list by which every case can be explained, but it does suggest that even without alien spaceships and undiscovered physical phenomena, many strange things will be perceived.

As an example of the complexities of just one class of objects, which has been inadequately studied both within and outside the context of UFOs, consider meteoroidal bolides. Bolides have produced exceedingly spectacular and unusual displays, but it is not widely recognized that they probably include a variety of objects. There are cometary debris, thought to be fragile and with a high volatile content, leading to fragmentation in the atmosphere. Many of these, having drifted in from the outskirts of the solar system have a very high velocity. Asteroidal fragments, thought to be represented by the stony and iron meteorites, enter the atmosphere at intermediate velocities and may have a different mass distribution. Least known of all, there may be a group of low velocity objects that are debris blown off the moon by impacts or in some other way captured in the earth-moon system. There may even be other unknown sources of cosmic debris.

The slow bolides (entry speed ~ escape velocity) are of particular relevance and interest because of the part that the epidemic of slow, green fireballs played in the development of the UFO problem in 1948-49 (Ruppelt 1956; Menzel and Boyd, 1963), and because of the scattered reports in the astronomical literature of majestic slow fireballs (Chant, 1913; discussed below). As an example of the diverse data bearing on the UFO problem, consider the possibility of observing fragments blown off the


moon. It is believed that interplanetary meteoroids striking the moon dislodge material amounting to some hundreds of times their own mass (Gault, 1964). Material totaling roughly the initial projectile's mass may escape the moons s gravitational field, probably in the form of particles much smaller than the original projectile (Gault, 1964). Ordinary meteors of mass 104 gm are of magnitude about -10 (Vedder, 1966), and we may infer that a fragment of such mass from the moon would produce a spectacular display as it enters the earth's atmosphere. That is, lunar-impacting projectiles of mass of the order 106 to 108 gm could be expected to throw out fragments that, entering the earth's atmosphere, could produce spectacular, slow fireballs. How often do such lunar impacts occur? Meteor fluxes have been thoroughly reviewed by Vedder (1966) and for the mass range given, the rate of lunar impacts is estimated to be in the range 10 to 10-1 per year. It is expected that many circumlunar particles would ultimately decay into the earth's atmosphere so that we may predict that every few decades, or even more frequently, spectacular slow fireballs of lunar origin should occur, and that groupings of these objects would appear over periods of weeks, since clusters of ejecta are thrown out by each lunar impact, to decay at different rates.

This illustration is chosen because the predicted characteristics match those of the "green fireball episode" and suggest that lunar debris may, indeed, be the explanation of those unusual bolides.

It is important to note that we have not yet even considered the possibility that any of the common or unusual causes in Table 1 may be badly reported, so that an investigator may become hopelessly confused.

Whoever believes that the UFO phenomenon represents revolutionary and fantastic events must take full account of the facts that (1) UFOs by definition include all phenomena unknown to the observer; (2) such phenomena are present in effectively infinite variety, so that even widely experienced investigators, not to mention inexperienced witnesses, may be unaware of them; and (3) such phenomena, even if accurately perceived, may be badly interpreted and reported by the observer.



3. Conception : The Re-entry of Zond IV Debris

It is remarkably common for astronomers, when queried about UFOs, to cite the misconceptions that accompany reports of meteors. Most astronomers have talked to witnesses who believe a prominent meteor landed "just behind the barn" or "just over the hill;" thus, they stress the limitations of verbal reports from average observers.

Project Blue Book has supplied us with exceptionally good data to illuminate this problem. On 3 March 1968 the news agency of the Soviet Union announced that the spacecraft "Zond IV" had been placed in a low "parking orbit" around the earth and would soon be launched into "outlying regions of near-earth space" (Sullivan, 1968). The mission was unsuccessful. At about 9:45 p.m. EST on 3 March, hundreds of American observers near a line from Kentucky to Pennsylvania saw a majestic procession of fiery objects with sparkling golden orange tails move across their sky. The spacecraft was disintegrating upon re-entry. Most observers saw two or three main pieces, while observers near the end of the path saw more. These objects were soon identified by NORAD as pieces of the Zond IV probe or its rocket booster and this identification was finally confirmed 1 July 1968 (Sullivan, 1968).

This case put us in the rare and fortunate position of knowing exactly what was involved even before we began to investigate the many UFO reports that were generated.

In brief, many of these reports were quite good, but there is an admixture of spurious elements that are astonishingly familiar to students of the "flying saucer" literature. The latter vividly illustrate the problem of conception and interpretation, and shed light on the entire UFO phenomenon.

Consider the conceptions that may be generated if one perceives three bright point sources moving across the night sky at constant angular separation of, say, 5°. The most objective observer may report as directly as possible the percept: three point sources moving with a constant angular separation. But this is just one end of a spectrum. A less objective observer and, from our Zond IV data, a demonstrably


more typical one may introduce subtle elements of interpretation. He may report three point sources flying with constant angular separation, or three lights flying with constant angular separation, or three lights flying in formation. These changes in conception may be subtle, but when the observer reports his conception to a second party, they may produce vividly different conceptions (especially if the second party is inclined to believe "flying saucers" exist). Further toward the other end of the spectrum, but less typical than the above examples, a highly unobjective observer may introduce totally spurious elements. He may report three craft flying in formation. He may, for example, conceive the idea that the three point sources are connected, since they maintain a constant pattern. He may even imagine a dark elongated form connecting them so that they become lights on a cigar-shaped object, or even windows on a cigar-shaped object.

This spectrum of the conceptions of observers is not based on mere theorizing. It is directly derived from the Zond IV observations.

Quantitative analysis of the observations is somewhat confused by their heterogeneity. The file supplied by Project Blue Book contains reports ranging from very complete accounts on official Air Force report forms to fragmentary records of telephone reports. In all, there are some 78 reports, but only about 30 detailed letters or forms attempting to give a complete description are appropriate for analysis. There are only 12 Air Force report forms from which one can study the variations in response to specific questions; e.g. angular size, velocity, etc.

Study of the file, some 30 complete reports produced counts of certain conceptions indicated in Table 2, listed in order of decreasing frequency.

The following remarks apply to the items in Table 2. Item (1) shows that virtually all the reports that made reference to sound correctly agree that there was none. One witness (item 16) reported sound like a piece of tin hurtling through the air. We can be certain this is in error; this conception must have resulted from an unrelated noise or a hallucination due to a belief that there ought to have been a sound. Items (2) and (14) are somewhat misleading semantic errors. A better


Table 2

Selected Conceptions Generated by Zond IV Re-entry*

CONCEPTION No. of Reports

1. Report absence of any sound 20
2. Report "formation" 17**
3. Estimate altitude or distance < 20 mi. 13**
4. Suggest phenomenon may be meteor(ite) or satellite re-entry 12
5. Report straight, uniform motion 12
6. Indicate individual sources were of angular size > 7' 10**
7. Report rocket- or cigar-shape, or "saucer" shape 7**
8. Report curvature or change of direction or motion 6**
9. Estimate altitude or distance at < 10,000 ft. 5**
10. Report cigar-shape or rocket-shape 5**
11. Report "fuzzy" outline 4
12. Report "windows" 3**
13. Describe lights (implying lights on something) 2**
14. Refer to exhaust 2**
15. Report sharp, well defined outline 2**
16. Report noise 1**
17. Report reaction of animal 1**
18. Report vertical descent 1**

*Based in effect, on about 30 relatively complete reports out of a total file of 78.

**Conceptions that are to greater or lesser degree erroneous.


choice of word than "formation" would have been "pattern" or "constellation." "Formation" and "exhaust" imply guided vehicles. One observer even described one object as "pursuing" another; it "looked as if it was [sic] making an attempt to shoot the other one down." (3) and (9): As is usually the case with meteor reports, the object was conceived of as being much closer than in fact. This presumably results from the average observer's unfamiliarity with the concept of watching objects a hundred miles away. (4): A number of observers correctly considered meteoritic phenomena. A smaller number flatly identified the apparition as a re-entry of some sort and a few even indicated that they gave it scarcely a thought until they later heard of the excitement generated through radio, and newspapers! (5) and (8): Most observers described an essentially linear path, but a smaller number reported changes in direction. A few even ruled out a meteoritic phenomenon on this basis. Most of the reports of change in direction must be subjective, perhaps an autokinesis effect, but some are thought to result from observers own motion in vehicles. (7): This includes all descriptions typical of "flying saucers," and (6), (7), and (10) together indicate a strong tendency to conceive of a shape even though the phenomenon involved virtual point sources. Most observers indicated that the fragments were about 3-4 mm. of arc in diameter, just within the resolving power of the normal human eye. Reports of a "cigar-shape" apparently stem from a subjective tendency to connect the string of sources and from popularization of this concept in the UFO literature. This important phenomenon I will call the "airship effect;" it is demonstrably present even in reports as far back as 1913, and in Cases 34 and 37. Items (11) and (15), which seem to indicate merely the inadequacy of the report form's question (The edges of the object were: Fuzzy or blurred? Sharply outlined?) in the case of a near-point source with an ill-defined tail. Items (12) and (13) illustrate serious misconceptions, apparently due to unconscious assumption that there was a vehicle. Item (17) refers to a report that a dog was noted to become upset and to huddle, whimpering, between two trash cans. According to her own testimony, the witness, was quite excited and the dog presumably detected this.


The Air Force report forms comprise a smaller set of more homogeneous data, since the questions are standardized. A range of conceptions are illustrated by the 12 report forms plus 5 highly detailed accounts, and are summarized in Table 2. The angular size, a relatively objective measurement, is fairly consistently estimated. The size, distance, and velocity estimates are hopelessly misconceived, as we have already seen, since the observers had no objective way of determining any of these (without realizing that a re-entry was involved). The estimates appear to be influenced by prior conceptions of and familiarity with airplanes. Typical errors exceed a factor of ten. Only four of the 12 respondents correctly noted that they could not estimate the speed. Of 17 observers, four chose to describe a "formation," and two, "windows."

An effect important to the UFO problem is demonstrated by the records: the excited observers who thought they had witnessed a very strange phenomenon produced the most detailed, longest, and most misconceived reports, but those who by virtue of experience most nearly recognized the nature of the phenomenon became the least excited and produced the briefest reports. The "excitedness effect" has an important bearing on the UFO problem. It is a selection effect by which the least accurate reports are made more prominent (since the observer becomes highly motivated to make a report), while the most accurate reports may not be recorded. In the case of Zond IV the two most lengthy unsolicited reports described the apparition as a cigar-shaped craft with a row of lighted windows and a fiery tail, while the correct identifications as a re-entry were short, in some cases recovered only by later solicitation of reports.

In summary, we conclude that all of the following factors demonstrably confuse reports of unidentified phenomena and make subsequent investigation difficult:

  1. Objects are conceived of in terms of familiar concepts, such as aircraft. This produces misconceptions of distance, speed, shape, etc.

  2. At least during the last decade conceptions have been heavily influenced by the "flying saucer" concept in movies, TV, and periodicals. Reports of "saucer-shape," "cigar-shape," and physiological reaction are probably a consequence.


  1. Due to the nature of certain cases, certain questions on prepared questionnaires or report forms become ambiguous or meaningless.

  2. The "excitedness effect" biases reports toward those containing more exotic conceptions.

  3. The "airship effect" causes some observers to conceive of a shape surrounding light sources.

It is scarcely short of amazing, and certainly suggestive, that the seemingly straightforward Zond IV incident produced a high percentage of the very phenomena that have puzzled students of the UFO problem. Table 3 lists a selection of such reports. We have, in fact, reports of

  1. a cigar-shaped object with windows and a flaming exhaust,

  2. a vehicle or craft that passed low overhead in utter silence,

  3. psycho-physiological response of dread, or in another case, an urge to sleep, and,

  4. abnormal behavior of a nearby animal.

To the extent that the argument for "flying saucers" rests on the strangeness of such observations, it is thereby weakened.

Of course, the important question in a case such as the Zond IV re-entry is not the quality of the worst observations, but rather whether the observations taken together did define and clarify the phenomenon. My own judgment is that, together, the reports would suggest a re-entry to anyone who was familiar with such a phenomenon. This results primarily from the vividness of this particular case, and the attendant diagnostic features: a bright bolide slowly disintegrating into many fragments, each attended by a train. Nonetheless, it must be said that only a fraction, about a quarter, of the reports point directly in this direction while about another quarter are misleading and the remainder insufficiently detailed to be diagnostic. A reporter or investigator coming upon the case in innocence would be hardput to distinguish the good from the bad reports.

Table 3 demonstrates that a large part of the UFO problem is a semantic one. One may point out that an accurate reconstruction of this incident would have been, after all, possible from the bulk of reports; but to generate a UFO case we need only (say) one to four


Table 3

Selected Descriptive Comments on Zond IV Re-entry

Nature of the object:

"[I heard on] news ... it was space junk. Never. It came down then went forward in perfect formation. So how can gravity be defied?"

"Suggestions: 1. Cylinder type rocket with two thrust rocket en- gines and one rocket engine in front for guiding purposes. 2. Meteor broken into three main parts. 3. Space or aeronautical craft."

"Observer does not think the objects were either satellite debris or meteors because they had a flat trajectory."

"Didn't attach much importance to the object because I thought it was a re-entry."

"Thought it looked like something burning up in space ... Thought it looked like a burn-in."

"I wasn't aware that I had seen anything unusual until the local TV newscast ... advised of many other sightings of same for miles around."

"Neither I nor my fiancee sighted any connecting lines [among the bright sources]. If there were connecting lines, it would have formed the fuselage of a B-52 only about thirty to forty times bigger."

"Could not see actual object."

Appearance of object:

"All ... observers saw a long jet airplane-looking vehicle without any wings. It was on fire both in front and behind. All observers also saw many windows ... If there had been anybody in the UFO near the windows I would have seen them."

"It was shaped like a fat cigar, in my estimation ... It appeared to have rather square shaped windows along the side that was facing us ... It appeared to me that the fuselage was constructed of many pieced or flat sheets ... with a 'riveted together look' ... The many 'windows' seemed to be lit up from the inside."

[It could be compared to] "ordinary saucer inverted without protru- sion on top; elongated a little more than a saucer. Protrusion on bottom midline and about 50% of bottom so covered."


Table 3 (cont'd)

"No flame was visible but ... quantity of golden sparks ... In my opinion it was a solid rocket type vehicle with three lights or three oval saucer type vehicles."

"Object had red and blue lights."

"Observed an unidentified object ... It was long and narrow with a light in front and in back there was a streaming tail ... The object was dark black, trail was yellow gold."

"Fiery orange, long and narrow."

"Definite disk shaped."

"It was like two disk-shaped lights in some planned position."

"Tail appeared as metallic sparks."

"Formation flight":

"They flew in a perfect military formation."

When asked if they could be meteorites, [witness] replied, "It would be the first time I ever saw meteorites fly formation."

"It appeared as if one object was in pursuit of the other. One object seemed to be traveling at a higher or greater speed than the one pursuing it. The pursuing object ... looked as if it was making an attempt to shoot the other one down."

Distance and dimensions:

"It was at about treetop level and was seen very, very clearly, just a few yards away.

A pilot "estimated each [tail] was about 0.5 mile in length."

"We saw two orange lights tailing [sic] about two yards apart."

Observer "felt that it would have hit in the wooded area south of (her city)."

Response and reaction:

"I really wanted to see a UFO. I remember saying aloud ... 'This is no natural phenomenon. It's really UFOs, I ... made an attempt to


Table 3 (cont'd)

communicate with them. I had a flashlight ... [and] signaled ... in Morse code ... No visible response elicited ... After I came into the house I had an overpowering drive to sleep ... My dog ... went over between the two trash cans ... and whimpered and lay on the drive between the cans like she was frightened to death ... High frequency sound inaudible to us?"

"Frightened my eleven year old son, who was out with his telescope."


"I heard there were [72] grass fires in this area on the day following this sighting. I would think there might be a possible connection."



witnesses to agree on and express misleading conceptions and other witnesses to be silent or (more commonly) non-existent.


4. Conception: Re-entry of Titan 3 C-4 Debris

An incident less widely observed than the Zond IV re-entry gave the writer an opportunity to compare his personal observation of the re-entry of satellite debris with verbal reports solicited from his community. The results are similar to those of the case described above.

On 28 September 1967, at 9:53 MDST I noticed from Tucson, a bright, orange-red stellar object drifting across the northern sky toward the northeast at a rate of about 40' of arc per sec. Though initially of about zero magnitude, it suddenly disappeared, giving the impression of a jet plane cutting off its afterburner. However, the object suddenly reappeared, then repeated the performance several times. During the last few degrees of the trail, some 5° -l0° above the horizon, there appeared to be a disintegration into several barely resolved fragments. A second or two later, another object appeared and followed the first one down to the last 4° of the trail. Meanwhile, a faint milky-white train which had been left by the first object brightened for about 10 sec., then faded, twisted, and broke up in a period of about 6 min.

The tell-tale features of a satellite re-entry were present: the object was too slow for a meteor, had the brightness fluctuations and color of a burning object, fragmented, moved eastward and left a train that was distorted by high altitude winds. A later check through the Colorado project indicated that re-entry of certain fragments of Titan 3 C-4 satellite 1965-82KD, had been estimated to occur at about 6:00 a.m., MDST, on 29 September 1967 (see also King-Hele and Quinn, 1966). Earlier, the satellite had exploded in orbit, and the fragments were spread out along the orbit, so that sporadic decays near the predicted time were not unexpected; the observation of a second fragment a few


seconds (some tens of miles) behind the first was consistent with this. Hence, the identification is regarded as virtually certain.

Rarely does the investigator himself have an opportunity to see the "UFO" being described. In order to take advantage of this oppor- tunity to compare my own observations to the conceptions and semantics generated, I solicited observations through a local newspaper.

Fifteen reports were received from the Tucson area by telephone. The reports ranged from quite accurate to quite misleading. The most misleading of the 15 was from an articulate woman who was to all appearances an astute observer. She clearly reported that the object fell between her and some mountains a few miles away, appearing in front of (south of) the mountains and below their crests. (This conflicts with other reports of observers located north and west of the mountains, as well as the known identity of the object.) Other misconceptions reported included: (1) red and green flashing or rotating light (possibly confusing the object with an aircraft that was near the witness?); (2) much bigger than a star, could see a round shape; (3) motion toward the west (confusion with another object?); (4) "Looked like it was coming down right at me. It scared me. It was like it was right over me - like a fat airplane - with a big window." This is a repetition of the "airship effect" in which the observer conceives of a light as an aperture in a black, unseen, larger form.

The writer had concluded (before the Zond IV results were avail- able) that roughly a quarter of the reports were accurate and articulate enough to be definitive, roughly a quarter contained seriously misleading elements, and the rest were sufficiently inarticulate or whimsical to be of no great value (It was "real red, like, you know, and pretty ... It turned [sic] a beautiful white streak ..."). A report made by an investigator arriving later would have depended on which conceptions he heard or adopted. The right selection would have cleared up any problem; the wrong one might have created a seemingly inexplicable and possibly celebrated UFO report.



5. Conception: The Great Fireball of 9 February 1913

C. A. Chant (1913a), in a 71-page report, gives a detailed account of the spectacular meteoric display of 9 February 1913. The series of disintegrating bolides passed from Saskatchewan ESE over the Great Lakes and over the New Jersey coast. Several "waves" of clustered objects were seen, noise was heard at least 50 mi. from the sub-bolide point, and ground shocks were reported. Other remarkable sporadic meteors were seen in various scattered locations around the world for a period of some days. Chant deduced that the height of the path, which followed the earth's curvature, was about 26 mi. and that the geocentric velocity was in the range 5-10 mi/sec. M. Davidson (1913) reanalyzed Chant's data, plus observations from Bermuda, and concluded that the object had a height of some 46 mi. over Ontario, and Chant (1913b) subsequently inferred that they reached perigee over Ontario, but were not destroyed, moving out into a new orbit when seen from Bermuda.

The phenomenon appeared rather like the Zond IV re-entry. It is well-described in the "extended extracts" from letters published by Chant. Clusters of stellar-like objects passed overhead, with tails several degrees long and accompanied by smaller, fainter objects. It is a subjective judgment, possibly influenced by some editing of the letters by Chant, that the 1913 reports are on the whole more objective than those of this decade. There are probably two reasons for this: (1) In 1913 the demarcation between "educated" persons, from whom Chant was likely to receive letters, and "uneducated persons," was greater. (2) In 1913, there was no widely known conception (i.e. pre-conception of mysterious saucer-shaped aircraft or spaceship (although several reports refer to the object as an airship). Further, the 1913 reports (as published) tend to be more descriptive; the word "meteor" is used in a non-generic sense simply to mean a bright object passing across the sky. There is little attempt among the correspondents to infer what the objects were.


Chant himself indicates that the reports varied in quality due to the process of conception and interpretation: "The reader ... will ... . see that intelligent people can differ widely in describing a phenomenon, and will be able to appreciate the difficulty I have had in discriminating between very discordant observations." He presents reports of nearly 150 witnesses.

The "airship effect" is clearly present. Consider these reports: (1) "The series of lights traveled in unison and so horizontal that I could think only of a giant flying machine. The lights were at different points, one in front, one further back, and a rear light, then a succession of small lights in the tail." (2) "They ... did not seem to be falling as meteors usually do, but kept a straight course ... above the horizon. Our first impression was that a fleet of illuminated airships of monstrous size [was] passing. The incan- descent fragments themselves formed what to us looked like the illuminations while the tails seemed to make the frame of the machine. They looked like ships travelling in company." (3) "The meteor resembled a large aeroplane or dirigible, with two tiers of lights strung along the sides." (4) The witnesses "reported that they had seen an airship going east. The heavens were brilliantly illuminated, and with the passage of the meteors a shower of stones was seen to fall." (This last element is not mentioned elsewhere and appears to be spurious.) (5) "I took it for an aeroplane with both headlights lit, and as it came nearer the sparks falling behind it made it appear still more like one. However after a minute or a minute and a half I could see it was a meteor ... It was very low, apparently just above the hills. (6) "My brother shouted to me, 'An airship! And I said, 'Mrs. M--- 's chimney is on fire! It looked that near ... To the eye they were little above the housetops." (7) " ... a voice from a group of men was heard to say: 'Oh, boys, I'll tell you what it is - an aeroplane race.'"

We have already noted in the Zond IV case that the angular size, a relatively objective estimate, was consistently measured. In this


case the description of the noise is remarkably consistent, perhaps because of the ready availability of a charming simile. Here are five consecutive descriptions of the noise: (1) " ... a heavy noise like a clap of thunder at a distance;" (2) " ... a low rumble which at first made me think it was a buggy going along the road from church;" (3) " ... like thunder, loud at first and rumbling every two or three seconds;" (4) " ... like a horse and rig going over a bridge;" (5) " ... like a wagon passing over a rough road."

There was more difficulty with conceptions such as angular eleva- tion and distance. As usual, the latter was grossly underestimated. (1) " ... midway between the horizon and the sky ..." (2) " ... midway between the earth and the sky ..." (3) They traveled no faster than a crow flies." (4) " ... never have I [seen] so many heavenly bodies moving at one time, or any moving so slowly or in so low an altitude." (5) "They looked to pass about one mile south and at an elevation of about 300 feet." (6) " ... I saw [it] for about half a minute. In that time it seemed to go about 150 yards." (7) "The position in the sky of the first one seemed very low, so low that at first I thought it was a rocket." (Skyrockets, of the fireworks type, were a common analogue).

Many more reports could be cited, illustrating comparison with familiar objects (kites, funnels, ships in formation), in some cases misleading, even though the reports taken together present a relatively clear picture. We again can conclude that a substantial number of misleading reports will be introduced in observations of unusual phenomena.


6. Additional Remarks on Percepts and Concepts

The "airship effect" and "excitedness effect" apply to the Eastern Airlines case of 1948 (better known as the Chiles-Whitted case). This will serve as an example of the difficulties of establishing any concrete evidence for "flying saucers" when one is forced to distinguish percepts and concepts of a few witnesses in older cases.


Briefly, pilot Chiles and co-pilot Whitted reported flashing by them in a few seconds a "wingless aircraft with no fins or protruding surfaces, [which] was cigar-shaped, about 100 ft. long, and about twice the diameter of a B-29 Superfortress. It seemed to have two rows of windows through which glowed a very bright light, brilliant as a magnesium flare. An intense dark-blue glow like a blue fluorescent factory light shown at the bottom along the entire length, and red-orange flames shot out from the rear to a distance of some fifty feet" (Menzel, 1963).

This case has been one of the mainstays in the arguments for "flying saucers" and NICAP has described it as the "classic" cigar-shaped object (Hall, 1964). Hynek, as consultant to the Air Force, and Menzel and Boyd account for it as a fireball (Menzel, 1963).

The present discussion provides definitive evidence that fireballs can be described in just the way reported by Chiles and Whitted. The investigator is faced with the perfectly conceivable possibility that Chiles and Whitted, suffering from the "airship effect," became excited and reported a misconception - a cigar-shaped object with windows and flames - just as a fraction of witnesses to spectacular fireballs are now known to do.

A second example from my own experience illustrates the difficulties of transforming perceptions into conceptions (and explanations). During the course of the Colorado project investigation, I was sitting in the left side of an airliner, just behind the wing. As I looked out over patchy clouds, I saw an object apparently passing us in the distance, flying the other way. It came out from under our wing, not far below the horizon, and drifted slowly behind us until, because of the window geometry, I could no longer see far enough behind to observe it. It moved like a distant airliner, but was a grey, ill-defined disk, with major axis about a third of the apparent size of the moon. It was darker than the clouds, but lighter than the ground. It appeared to be a disk-shaped, nebulous "aircraft," flying smoothly in an orientation parallel to the ground.


I was sufficiently shaken by this to pull out some paper and begin making copious notes. During this operation I glanced out again and this time saw clearly a distant airliner, slightly above the horizon this time, but moving in the same way. There was no question that this was an airliner, for in spite of its having the same angular size as the disk, I could clearly see its wings and tail. Just then, the pilot banked to the right, raising the left wing, and suddenly the distant plane became a grey, nebulous disk. It had passed behind the distorting exhaust stream of the jet engine, which was suspended and obscured under the wing. The first disk, or plane, had flown directly behind this stream, whose presence had slipped my mind.

In summary, an investigator of UFOs is in effect asking for all the records of strange things seen, and he must be sober in recognizing the tremendous variety of sources of distortion and misconception. Each case of misconception may involve its own processes of error, but perhaps common to all such cases is an easy tendency to "fix" on an early conception of a percept, by a process that is analogous to that of the "staircase" optical illusion in which one conceives of the staircase as being seen either from "above" or "below". Another example is the common difficulty in looking at aerial photographs. One may conceive of the relief as being seen either "positive" or "negative." Once the conception occurs it is difficult to dispel it. If you see a star at night from an airplane but conceive of it as an object pacing the aircraft at only 300 yd. distance, it is easy to retain this conception. As R. V. Jones (1968) has pointed out (reviewing his wartime intelligence investigative experience in the context of the UFO problem), "witnesses were generally right when they said that something had happened at a particular place, although they could be wildly wrong about what had happened." (WKH emphasis).


7. Reporting

"Reporting" means the process of transmission of the observation - from the observer to a journalist, Air Force investigator, the police,


etc., and from there to the public. Reporting, we have found, is one of the most crucial factors in the UFO problem. My own conclusion has been that one must not form a judgment of any case from the popular literature.

Suppose, for example, that the pilot of my airliner had not banked the plane wing, and I had not learned the explanation of the grey, nebulous, elliptical object. I would have submitted my report, not of a "flying saucer," but of an object I could not identify. Assuming that the story got out, it is highly probable that because of its clear news value ("COLORADO PROJECT INVESTIGATOR SEES DISK"), it would have been publicized before anyone established that the jet exhaust had produced the phenomenon. Such a story, brought to public attention by newspapers and magazines, would stir more pressure on public officials and contribute to the illogical but widespread feeling that where there is so much smoke there must be some fire. A later solution would not be so widely publicized.

Ruppelt (1956) discusses another example that occurred in actual fact. The famous Maury Island Hoax, which even today stirs interest, was widely publicized. The story was sensational, in that it involved alleged fragments of a saucer that had been seen to explode. Two Air Force investigators on the case were killed in an accidental plane crash. The case was later clearly identified as a hoax. Ruppelt remarks,

The majority of writers of saucer lore have played this sighting to the hilt, pointing out as their main premise ... that the story must be true because the government never openly exposed or prosecuted either of the two hoaxers... the government had thought seriously of prosecuting the men, (but) it was decided, after talking to the two men, that the hoax was a harmless joke that had mushroomed... By the time the facts were released they were yesterday's news. And nothing is deader than yesterday's news. (WKH emphasis).


Many writers in our culture, from fanatics and hypocrites to sincere reporters, are not, after all, committed to complete investigation and understanding of the subject, but to telling and selling a good story. Unfortunately there is a selection effect: if a "flying saucer" story is investigated too completely, and is found to be a misperception or a hoax, its interest and sales value are reduced.

Examples of journalists' distortion and slanting, conscious or unconscious, abound: misinformed amateurs quoted as authorities, repetition of hearsay evidence, and naive selection of data are examples of such dubious reporting. The UFO literature is full of the following sort of ill-advised criticism of non-believers: Edwards (1966) describes a case in which a world famous astronomer and authority on galactic structure, and two colleagues, reported that they had seen a "circular, luminous, orange-colored" light pass overhead too slowly to be a meteor. Noting that on the following day the Air Force, rechecking their files, found that the case was explained by two Vampire jets and a jet trainer on a routine training flight at 20,000 ft., Edwards then concludes with the remark, "If a professional astronomer really were incapable of telling one circular object from three jet planes at 20,000 feet, how reliable would his work be regarding an object 40 million miles away?" Aside from the facts that the "explanation" was not the astronomer's responsibility and that the latter figure misrepresents the scale of that astronomer's work by a factor of a billion, this concluding statement certainly shed no real light on the UFO problem, but rather creates a state of mind that may aid acceptance of the author's later remarks.

Jones (1968) illustrates well the problem of forming a reliable judgment from diverse reports of individuals on a single phenomenon. During the war, a British and an American physicist had the task of establishing from sailors' reports the German pattern of mine-laying at sea. One of them went on a field trip and discovered that reported ranges and bearings were unreliable; only the question of whether the mine was to the port or starboard was reliably answered. With this


discovery, he solved the problem while his counterpart became bogged in a mire of meaningless data. The point is that by actual field interviews one may get some idea of what happened, but under no circumstances, simply because a witness says (or is reported to have said) that he saw a cigar-shaped object, should one assume that a cigar-shaped object was really there

This well known rule applies in many other fields of investigation. Jones states: "I have made this discursion into some of my war experiences because it is relevant to the flying saucer story in that it illustrates the difficulty of establishing the truth from eyewitness reports, particularly when events have been witnessed under stress. I do not, of course, conclude that eyewitness reports must be discarded; on the contrary, excluding hoaxers and liars, most witnesses have genuinely seen something, although it may be difficult to decide from their descriptions what they really had seen."

There is still another problem: even if reliable reports are prepared, communication among investigators is so poor that the reports may not be read. Scientific journals have rejected careful analyses of UFO cases (apparently in fear of initiating fruitless controversy) in spite of earlier criticism (in the journals' own pages!) that the problem is not discussed in the scientific literature. Even at the most responsible levels, communication is poor. The House Committee on Science and Astronautics, in its 29 July 1968 hearings, received accounts of allegedly mysterious cases that already were among the best-explained of those studied by the Colorado UFO Project.

In order finally to demonstrate the very poor manner in which the UFO problem has been presented in the past, primarily in the popular literature, consider two imaginary accounts that could be written of the Zond IV re-entry, one by a sensationalizing, but perhaps sincere reporter, and one by a more sober investigator. Of course each reporter can back up his story with taped interviews and sketches.


A fantastic cigar-shaped object that entered the earth's atmosphere from space on 3 March 1968 is unidentified. Although some Air Force officials attempted to pass it off as a satellite re-entry, examination of the official Air Force papers indicates a reluctance to identify it with any known spacecraft.   Although there was some preliminary uncertainty in Air Force circles as to the nature of the bolide of 3 March 1968, after several days study of the reports it became clear that the event was a satellite re-entry. This was confirmed some months later.
The absurdity of the satellite explanation is proved by the reports of the witnesses who got the best look at the object. Witness after witness described the object as cigar-shaped, with a row or rows of windows and a flaming exhaust. Several others mentioned saucershaped lights visible as the craft flew overhead. Many observers, who apparently did not get such a good look at the mysterious craft, merely described a strange formation of lights.   While the re-entry was was confirmed by the bulk of the actual observations, it was badly misinterpreted by several excited witnesses, who wrote the longest reports and described the object as cigar-shaped. There was a tendency for some observers to interpret the string of disintetrating meteors as windows in a dark craft. Still others interpreted the yellowish tails of the objects as exhausts. Such misconceptions were widely scattered but in the minority.
There is little doubt that the craft came from space. The probability that it was under powered flight is raised not only by the exhaust but also by several observers who saw it change direction.

This event, witnessed by hundreds in many states, provides one of the best proofs yet that some kind of strange airships have invaded our atmosphere.

  Entering the atmosphere, the satellite grew incandescent and began to disintegrate into dozens of pieces, each moving at its own speed because of drag. Autokinesis effects were not uncommon among the ground observers, as the objects appeared as slowly moving light sources in the dark sky.



8. Reports: The Credible Number of "Flying Saucers"

Most readers of this report will perhaps be convinced that alien spaceships or some other unknown phenomena can be involved in only a very small percentage of all UFO reports or perhaps in none. Yet there is a curious tendency on the part of many students of the problem to imply that the sheer number of reports somehow proves that there must be some physical reality involved. For example, J. B. McDonald (1968) argues before the House Committee on Science and Astronautics, in a one-paragraph statement on witness credibility: "... It seems tedious to enlarge here on those obvious matters. One can be fooled of course; but it would be rash indeed to suggest that the thousands of UFO reports now on record are simply a testimony to confabulation, as will be better argued by some [selected cases]." Jones, who argues against the probability of any substantial number of flying saucers says: "There have been so many flying saucers seen by now, if we were to believe the accounts, that surely one of them must have broken down or left some trace of its visits. It is true that one can explain the absence of relics by supposing ... fantastic reliability ...

It would seem to me that if one begins by studying both witness reliability and selected cases, and if one thereby realizes that it is quite conceivable and probable for the great bulk of reports to be simple mistakes and fabrications, then arguments invoking the enormous number of reports become irrelevant. We are concerned by only a small "residual" of puzzling reports.

This raises another approach to the UFO "residual" reports. We could attempt to answer the question: what is the maximum frequency of spaceships that could actually have penetrated our airspace and still leave us with such meager evidence as we have for their existence? Obviously if a 30-ft. metal disk hovered over the Capitol for some hours, we would have a multitude of photos, video tapes, and other hard evidence from different observers in different positions.

Some measure of public reaction to spectacular and unfamiliar celestial phenomena can be gained from study of fireball reports. Six


spectacular fireballs were studied to this end using analyses by C. P. Olivier of the American Meteor Society (1962, 1963, 1967) and reports in Sky and Telescope. Among these, the longest duration was only 31 sec. for the 25 April 1966 object; yet even for an object of such short duration, a number of photographs were made. In other cases, dust trains of duration up to 17 mm. were photographed and widely reported. The Zond IV observations are also applicable. These data permit estimates of the frequency of both visual and photographic reports.

The fireballs were brighter than the full moon in most cases. Often they appeared not as point sources, but as a disk about half the size of the moon. Some of them were bright enough to attract the attention of persons indoors; some of them were accompanied by thunder-like explosions. All attracted national publicity. In short, they are remarkable enough to have attracted attention and photographs, and are thus considered comparable to hypothetical, well-observed "flying saucers" in public response.

The analysis must take into account the number of inhabitants in the area of visibility as well as the duration of visibility. We may call the product of the number of inhabitants times the duration, the "exposure" of the phenomenon. We can ask how the total number of actual witnesses is related to the exposure.

For short-period durations (a few minutes) it is reasonable to expect that the number of witnesses (a fraction of the number of inhabitants) would be proportional to the exposure. This can also be assumed about the number of detailed reports recovered by investi- gators who solicit them, and about the number of photographs. In the fireball and Zond IV cases there are data giving number of witnesses, number of recovered reports, or number of photographs. Thus, if N is the total number of inhabitants, and t is the duration of the event (sec.), we have a first-order theory of the form

no. witnesses = NW = CWNt,


no. recovered reports = Nr = CrNt,

no. recovered photographs = NP = CPNt.

It is possible to identify the proportionality constant, C from the reports mentioned above. Derived values are listed in Table 4. The constant 1/C has dimensions man-sec/witness (or /report, /photographer). For example, the Air Force files on Zond IV yield 78 reports for a two-minute phenomenon visible from a region inhabited by an estimated 23,000,000 persons, giving 3.5 x 107 man-sec to generate one report. It is clear that the number of photographs generated will depend on the duration of the phenomenon in a more complex way than indicated in our simple equation, since with durations longer than some limit, more witnesses will have time to obtain a camera. In this approximate and first-order treatment, this complication is neglected.

Application of Table 4 can be illustrated by the fireball reports. The original data suggest about 500 reports in five years for these very bright objects. We assume that the average fireball is visible roughly 10 sec. These figures allow us to solve the equation (cited above) for the number of inhabitants through whose skies pass fireballs in five years. If it takes 6 x 106 man-sec. to generate one report (Table 4 ), then the fireballs must have been exposed to about 300,000,000 people. This figure is expected to be accurate to something better than an order of magnitude. That is, every citizen of the United States evidently has such a fireball in his sky about once every few years (whether or not he is outside and sees it). This is in good accord with known data - Vedder's (1966) estimate of the flux of meteors of magnitude -15 is one every three to four years over an area of the size of the United States.

The question before us is how many of the UFO reports could correspond to real objects in view of the available data. Is a "residual" of even 2% of the cases reasonable? We have three relevant statistics:

  1. National opinion surveys indicate that roughly 5 x 106 persons of the total U. S. population believe they have seen UFOs in 20-year interval since they were first reported. If 2% of these represent really strange unknowns, we should have 1 x l05 witnesses.


Table 4

Response to Unusual Aerial Objects*


17 November 1955 France   6.0x106  
16 January 1961 California 5.0x104    
23 April 1962 New Jersey   1.5x106 6.0x109
25 March 1963 Maryland   9.1x105  
9 December 1965 Michigan   5.3x106 < 1.2x1010
25 April 1966 New York 3.1x103 5.4x106 < 4.0x108
3 March 1968 (Zond IV)   3.5x107  
Adopted Value   104 6x106 5x109

* These figures are understood to apply only to short-duration sightings, since, obviously, by extending the duration one cannot obtain more witnesses than the number of inhabitants.


  1. There have been roughly 15,000 recovered cases, representing perhaps 45,000 individuals' reports. A 2% residual would give 900 reports of unknowns.

  2. The project study suggests that the "residual" photographs of unidentifieds number of the order of 20.

Combining these three statistics with the three constants from Table 4 we derive three independent estimates of the total number of citizens exposed to the "high-strangeness residual UFOs" in the last 20 years; viz., 2x107; 1x108; and 2xl09. It can be seen that the accuracy is no better than an order of magnitude. However, taking 200,000,000 persons as a representative value, the implications are clear. The results suggest that merely to generate the 2% residual, every person in the country has had an UFO visible above his horizon once in the last 20 years.

Of course, since most man-hours in this country are spent indoors, or asleep, or paying no attention to the sky, it is not surprising that very few people have reported seeing such craft. But taking into account the array of automatic surveillance equipment operating in this country, it does border on the incredible that the "hard" evidence should be so scanty. The statistic is similar to the five-year statistic for bright fireballs, and although the "evidence gathered over an arbitrary five-year time span for the existence of bright fireballs" is similar to that gathered over 20 years for "flying saucers" the "fireball evidence" is perhaps more convincing : it includes detection by automatic survey cameras, large numbers of witnesses per incident, and more reliable witnesses. To accept as many as 2% residual cases as examples of extraordinary aircraft, then, is to accept that an UFO could fly around the country in such a way as to be potentially visible to, or in the sky of, every citizen for 40 sec. without being positively recorded or conclusively reported.


9. Conclusions

As we have already stated, some students of the UFO problem have used the argument, either directly or by implication, that where there


is so much smoke there must be some fire, i.e. that some of the UFO reports must involve truly extraordinary phenomena such as alien space-ships or unknown meteorological effects. This chapter is addressed to the question: is it conceivable and defensible that all of the UFO reports could result from mistakes, illusions, unusual conditions, and fabrications?

The answer appears clearly affirmative, although we claim no proof that all reports can be so explained. We have looked at a three-stage process: a perception is received of some unusual apparition; a conception is created by interpreting the percept and combining it with prior concepts; a report is eventually made to an investigator or on some public document. Each step introduces possibilities for error.

The number of phenomena and combinations of phenomena that can produce unusual percepts is so enormous that no investigation can begin with an a priori list of explanations and expect to match one to each case. The variety is effectively infinite and it must be realized that in effect the investigator is asking for a report each time an unusual percept is generated. Obviously, this will be frequent.

Our data demonstrates beyond question not only that weird and erroneous concepts are widely formed, but also that these erroneous concepts are often precisely those that show up in the UFO phenomenon. Perhaps as a result of their popularization in the UFO literature, the phenomenon feeds on itself to a certain extent.

Finally, the reporting processes are demonstrably such that very low signal-to-noise ratio is generated. That is, certain social forces conflict with clear, concise, and thorough presentation of UFO reports. Sarcasm is employed at the expense of logic. A whole body of literature exists by virtue of the sensational aspects of the problem.

In conclusion, it appears that the number of truly extraordinary events, i.e. sightings of alien spaceships or totally unknown physical-meteorological phenomena, can be limited to the range 0-2% of all the available reports, with 0 not being excluded as a defensible result.




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