The UFOs of October:
The Autokinetic Effect and
group dynamics in UFO observations
Michael D. Sofka
This is the outline of a talk presented to
The Inquiring Skeptics of Upper New York, February 3, 1999;
The Syracuse Technology Club, May 11, 1999;
to the Albany Area Amateur Astronomers, November 16, 1999; and,
The Central New York Skeptics, September 20, 2006.
Slides and notes available in PDF.
Thank you to Taner Edis, Alan French, Eric Krieg, Bob Mulford and
Gary Schwartz for their feedback and suggestions.
My talk today is about the perceptual effects that lead many sane,
sober people to believe they saw something unusual in the sky. These
are the ``lights in the sky'' reports. The sightings which result in
calls to the airport or planetarium.
In the interests of full disclosure, I personally don't believe UFOs are
alien space craft. But, a lot of people, as many as 11% according to
some polls, believe they have seen something unusual in the sky, which
they identify as a UFO. If these people are not delusional, or
impaired, then what did they see? That is the question I will
be answering, at least in part, in this talk.
I am specifically going to discuss the autokinetic effect and other
illusions of motion that contribute to most, if not all, UFO reports.
I'll also be talking briefly about the effects of expectation on
perception and recall. The message to take home is that ordinary people
can see something unfamiliar in the sky, and interpret it in ways
consistent with what they expect of UFOs, even though in reality they
saw nothing unusual or abnormal.
I won't be talking about Alien Abductions, Fox Autopsy films, Crashed
Flying Saucers, Cattle Mutilations, UFO cults or any of the more exotic
UFO-related claims. I also won't be talking about hoaxes, although
there have been some famous UFO hoaxes. And, I won't be covering the
history of UFOs, even though I find that topic to be fascinating in its
Any of these other topics could be the source of many other talks. But,
I'm going to stick to your basic bread and butter ``lights in the sky,''
which still make up the majority of UFO reports, and are the foundation
of the pyramid of UFO claims. That is, if there were no underlying
real phenomena---the illusions of motion---there would be many fewer
reports of ``lights in the sky,'' and they would not have the
same degree of credibility. Without that base, hoaxed UFO photos,
and claims about finding a landing site, or talking with occupants
would be less believable.
To tie the talk to a particular, ``real,'' event, let me read to you
from an October, 1994 Albany Times Union article entitled:
``Twinkle twinkle little starmen?''
- Clairmont Road residents were drawn outside Friday
night by red and green blinking lights in the sky....
- ``A whole bunch of people witnessed this, including
a member of the Stillwater Police Department,'' said
Ray Cecot of Niskayuna, section director of the
Mutual UFO Network. ``I have multiple witnesses
all saying the same thing. Nobody was drinking;
there were no drugs around.''
- The lights were first seen at about 8 pm by a woman
and her daughter, who won't speak to the press. About
seven neighbors came out to watch,....
And, the report goes on to elaborate that there were up to a dozen
saucer shaped objects the size of a dime held at arms length.
Think about that for a minute, 12 objects the size of a dime held at
arms length. How big is that? If you held a dime at arms length, how
would it compare in size to the full moon?
Two television news stations even showed up, and filmed the object---the
film crew saw only one---the next day, which provided an inadvertent,
but very important, clue.
Skeptics and UFOs (Disclaimer I).
Before discussing the UFOs of October, a little background is in order:
background on illusions of motion, on group dynamics and, most
importantly background on Skeptics.
Skeptics attempt to apply science and rational methods to
claims of the paranormal and fringe science. They work within
established scientific framework, although some creativity may be
necessary to apply science to such bizarre areas as UFOs, bigfoot
sightings, and so on.
I contrast this ``scientific skepticism'' with ``philosophical
skepticism,'' which takes more of a doubting Thomas approach to
claims. The philosophical skeptic is likely to doubt anything they
don't see themselves, or at least strive for complete consistency
in all aspects of belief. I'm more concerned with what science can
tell us, and leave the non-scientific alone.
For example, since it is believed likely that there are some
extraterrestrial intelligences, and since they may exceed our technology
by millions (even billions) of years, we cannot dismiss out of hand
the claim that some UFOs are of extraterrestrial origin.1 But:
- If that is the case we should be able to find some
positive evidence that UFOs are not of this earth--such as a
piece of metal whose isotope ratio is different from that of the
earth metals (and, preferably, different from that of meteoric
iron and nickel).
- Negative evidence---for example, a blanket claim that we
can't explain with 100% certainty what Mrs. McDonald saw on the
night of September 1st, is not evidence that UFOs are
extraterrestrial, or even something unusual. It is only
evidence that Mrs. McDonald saw something she was unfamiliar
with or could not identify under the circumstances.
- Most UFOs can be identified, or they have good competing
explanations, such advertising airplanes, satellites,
weather balloons, or celestial objects enhanced by common but
illusions. A skeptical investigator strives for this type
of explanation---it has a far greater probability of being
correct. A good investigator (skeptical or not) attempts to
use science to eliminate the normal---if only to highlight
the better claims.
I want to emphasize: it cannot be claimed with 100%
certainty that the effects I'll be talking about are the
explanation for any particular event. But:
With those preliminaries out of the way, lets get to some science.
- They are good and simple theories, which
should be considered before jumping to more complicated explanations.
- They are frequently overlooked
explanations---particularly by those who believe they have seen
a UFO, or those who want to believe UFOs are spacecraft.
- They are frequently misunderstood even by
those who do not believe UFOs are extraterrestrial
spacecraft, and are instead invoked in a form
of hand waving.2
What is the Autokinetic Effect?
I've already mentioned the autokinetic effect, and it is
in the title of the talk. What is the autokinetic effect?
The Autokinetic effect is a perceptual illusion in which motion
is perceived in an object that is really stationary. It is
an illusion of motion---and a very common one.
It is most often perceived when a small bright object is
seen against a dark background, such as a keyhole in a dark
room3, or a bright star against the evening
It is caused by small eye-movements. Our eyes are
constantly moving, the brain compensates for this movement
to create a stable image. When compensating, the brain is
using prior knowledge of background---that is, knowledge of
what does and does not move.
Against an ``impoverished'' background, however,
the brain mistakes the eye's movement for object movement.
Once your brain has made the ``decision'' that the object
is moving, the effect is persistent and very realistic.
The autokinetic effect is robust:
- Everybody will see it under the right conditions, and the
right conditions are easy to find. The Early evening sky
is an ideal condition.
- It has been replicated in laboratories literally
thousands of times as part of experiments on perception,
and group dynamics (which I'll talk about shortly).
A good time to see it is right now [January 1999] in the early evening:
- Jupiter is high in the southwest at sunset.
- Look for it about 5:30--6:30, as it gets dark,
but before all the stars are visible.
- Just stare at it for a couple of minutes, choosing
a vantage point that provides little background. (For example,
not through the limbs of a tree). Eventually, Jupiter will
appear to move.
Once the illusion of motion has set in, it is
difficult to ignore; even if you know the object is
stationary, it appears to move.
To those who do not know what is happening, it is
very difficult to convince them their eye, and not the
object is moving.
Muzafer Sherif's study.
The autokinetic effect is also subject to suggestion. That is, you can
suggest to people what ``motion'' the light is making. Multiple people
can also make suggestions to each other about what they see without
realizing what they are doing. When this happens, the autokinetic
effect becomes an unintentional Ouija board.
In 1931, Muzafer Sherif, a social psychologist, used the autokinetic
effect to study the formation of group norms.5 Group norms are accepted beliefs or
behaviors in a group of people. For example, how close should you stand
to another person during a face-to-face conversation.6
In Sherif's study:
- Subjects were placed individually in a darkened room with
a single light source on the opposite wall. They were asked to
record how far the light moved. Note, the light did not
move, it was solidly fastened to the wall! So,
what the subjects were really recording is how far they
perceived the light be moving due to the autokinetic effect.
- By themselves, the subjects soon settled on individual
estimations of movement, ranging from a couple of inches
to about 8 inches.
- When the subjects were then put in a room together, and
encouraged to report their estimates out-loud, Sherif found that
their estimates at first differed, but soon converged on an
common value. But, the value was not necessarily the arithmetic
mean. A single subject's value often dominated or exerted
- Finally, when the subjects were separated, they maintained
the group estimate for light movement.
- By running this experiment, Muzafer Sherif inadvertently
ran the first controlled experimental study of UFO observation 16 years
before the first UFO was spotted by pilot Kenneth Arnold.
Sherif's results are also robust, and have been replicated
in hundreds of subsequent studies of group
dynamics. It turns out to be trivially easy to influence
what movement the light is reported to take, and groups of subjects
always come to some agreement on what they are seeing. For example:
- A confederate (somebody working with the
experimenter) can influence the perceived distance and
direction of movement.
- Exaggerated distance norms can be established (e.g., if
most subjects perceive 6-10 inches, a confederate can establish
a norm of 15 inches.
- Group norms persist over ``generations'' of subjects, as
each is replaced by a new group member. The exaggerated norms
typically persist for 5--7 generations, before reverting to a
Other Perceptual Effects.
The autokinetic effect is not the only illusion of motion that
has a role in UFO reports. For example, there is also:
Autostatic Effect: Similar to the autokinetic effect,
the autostatic effect is when a moving object appears stationary. This
can happen, for example, when watching a satellite traverse the sky.
Many people do not realize that you can see satellites with the naked
eye, and they are another suspected source of UFOs---one which is
difficult to track down since orbital data for satellites can be
difficult to come by (some is classified). [This is changing, however,
as more programs for calculating orbits based on observation become
available via the Internet. There are also active satellite watchers,
and web sites with links to orbital information. See
ftp://kilroy.jpl.nasa.gov/pub/space/elements/satelem/. --mds 29 September 1999, thanks to Allen Thompson
for bringing these web sites to my attention.]
Stroboscopic Effect: lights blinking in sequence
create an illusion of motion---for example, stars being
seen through wispy clouds.
Induced movement: An object may be perceived to move when
it is the background that is really moving. We are all familiar
with this from sitting in a car, and jamming on the brakes in panic when
we think the car is moving backwards, only to discover that it
was the car in front moving forward. This also happens when we
watch the moon or a star ``racing'' through clouds on a windy night.
Moon or star chasing: The moon and stars are
so distant, that they do not change position against the background
when we move. This creates the illusion that they are following us. If
that is combined with some other event, such as a fireball, or if it
occurs when a person is nervous or tired, a UFO encounter may be in the
Brightness/Size/Distance constancy: In the absence of other cues a
brighter object is perceived as being larger and closer than a dimmer
object. In the case of stars, they are all the same size to the naked
eye---they are all point sources. Yet, the brighter stars are perceived
and remembered as being ``bigger.'' (An amateur astronomer friend
remarked that people will ask him about the star that was ``as big as a
Atmospheric shimmering: can make a steady object
appear unsteady, and can cause a prismatic effect so that a white object
may appear to change colors. This often creates an illusion of
rotation, as colors shift (similar to the stroboscopic effect).
It should be noted that training does not make these effects go away.
At most, training can alert people to when they may experience an
illusion of motion or perception, and take action (such as viewing the
``UFO'' through tree limbs) to eliminate or adjust for it. Or, when
they should temper or compensate their answers for such effects.
It should be specifically noted that pilots and military personnel do
not get special training in how to ignore optical illusions, or how to
observe the night sky. Quite the contrary, more advanced pilot
training includes ignoring sensory feelings and believing instruments.
Our senses can lie, we must trust our instruments. As such, reports
of UFOs by pilots are as accurate or inaccurate as those of non-pilots
under the same conditions.
Memory of a UFO observation are also influenced by recall
effects. What a person recalls seeing is influenced by what they
believe they have seen---especially in an ambiguous and emotionally
charged event such as a crime, or observing a UFO.
Elizabeth Loftus and her students:8
- Showed people a movie of an auto accident.
- Asked them how fast the car was going when it
ran the stop sign. But, there was no stop sign---it
was a yield sign.
- Regardless, most subjects later recalled a
stop sign they didn't see.
- Also, their estimates of how fast the car was
traveling when it ran the non-existent stop sign varied
with how the question was asked. So, if the question
implied a high speed, the estimates were higher. Loftus
calls this a ``leading question.''
It is important to keep in mind that:
Most UFO observations are not due to a single effect, and instead
involve a collection of perceptual illusions which our brains tie
together into a narrative consistent with what we believe we saw.
A sighting may start by looking at a very bright ``star,''
and through a combination of perceptual illusions and leading questions
(from other group members, or from investigators) ends with reports
of dime sized saucers. It is important to remember that both
perception and recall are active events influenced by what we
believe we are/were looking at.
The Autokinetic Effect in Practice.
Ok, we know the autokinetic effect, and other illusions of motion,
exist. And, we know that group dynamics can greatly influence
the illusion, and the consistency of their reports. What evidence
is there that this has ever happened with ``real'' UFOs?
The Exeter, New Hampshire UFOs.
- In the fall of 1965 in Exeter, NH, multiple people
reported UFOs that followed their car from the beach, or
were visible from their back porch. The UFOs were reported
to move, rotate, etc. This went on for three months.
- This was widely reported in the newspapers,
getting more people to look, and was written about in the
book Incident at Exeter, by John
- Robert Sheaffer plotted times of sighting, as
given in Fuller's book,
with the setting times of Jupiter. He found a total of
7 observations that provided enough information to tell
such basics as the direction in the sky, and day of the year.
These 7 observations, however, were a good
- If the UFO was not Jupiter, then we might expect at least
some of the Exeter UFO witnesses to give the location of the
UFO in relation to Jupiter. That is, Jupiter was bright and
visible. So, where was Jupiter in
relation to other bright and visible object?
The Mexico City UFOs.
- July 11th, 1991, Mexico City, a total eclipse
of the sun visible at noon with the sun near zenith.
- Thousands of people watch as the eclipse
- Hundreds, thousands? More, depending on who you ask, see
a UFO zipping around. The UFO is captured on hand held
camcorders, and form the basis for a later
- But, if you wanted to know what people saw,
instead of watching the documentary I would suggest
the July 1991 Sky&Telescope. On page 89
is a map of the major celestial object visible during
the eclipse. This includes; the planets Mars, Venus, Jupiter and
Mercury, and the stars Regulus, Sirius, Betelgeuse
and Rigel---all except for Mars brighter than magnitude
1 objects---that is, objects as bright as the brightest
stars typically visible.
- Quoting John Bortal of the Brooks Observatory,
page 91 ``Mercury, Venus, Mars, and Jupiter site well
above the horizon during totality.... At magnitude
-5 [about 25 times brighter than Sirius], Venus
should be evident to the naked eye long before the
onset of totality.''
- If a UFO was recorded in Mexico City during the July
1991 eclipse, I would like to know its position relative to
these stars and planets, and particularly in relation to Venus.
- The Mexico City event, however, has spark a
long-lasting wave of UFO reports from Mexico, which
seems to have borrowed most of its major elements
form US UFOlogists.
The 1993 Perseid Meteor Shower, Bartlett, New Hampshire.
This final story is one of a personal nature.
- In 1993, I was vacationing in Bartlett, NH with my wife,
father, step mother and family. This was in August, so I had
the entire crew out, just before sunset, to watch the Perseid
- After we were lying on our backs for a few minutes,
watching the sky, my father points to a bright object and says:
``that star is moving!''
- Now, I'm an ethical person and a skeptic to boot, so I
said: ``No it's not, that's Vega, and you're just experiencing
the autokinetic effect.''
- After a couple of minutes pause, my father responds:
``Dammit, that star is moving, I can see it.''
There was a fair sized crowd observing at that time, many were looking at
us, and at Vega. They looked back and forth---I looked at them, and my
father, and they looked back. The temptation was very strong to say:
``you're right, it's moving to the left---look at it!'' (all in the
interest of Science, you understand). Never before was I so
upset about being an ethical skeptic.
The autokinetic illusion, once it starts, is very strong. Knowing
the object isn't moving, doesn't make it go away.
The UFOs of October.
I started off by reading from the Albany Times Union, about
UFOs seen over Stillwater NY. I hope by now you have a better
understanding of the kinds of effects that
may have lead to those reports.
What other evidence is there that the Stillwater UFO was a
bright planet or star?
- At that time Arcturus and Capella (the second and third
brightest stars visible from Albany), were in the northwest and
northeast, and Venus and Jupiter were both visible, and very
bright in the southeast.
- I first heard about the UFOs, was on the local news
station, WRGB Channel 6. The people being interviewed said the
lights were moving around the sky.
- The WRGB report included video footage of the object
witnesses said was the moving UFO. It showed a bright image of
a star or planet, rock steady in the tripod mounted camera image. The
weather came on immediately afterwards, and the meteorologist
(who is also an amateur astronomer) instantly said ``That was
Venus you showed.'' It was a gem of TV news moments.
- However, if WTEN Channel 10's meteorologist had a theory, he
was quiet about it after they showed the same rock-steady video
image from a tripod mounted camera. Not surprisingly, since their
anchor had just finished saying ``while driving home I
saw something very bright---brighter than a star---on the
- In later follow-up, not printed in the news or covered
on TV, Ray Cecot found that in the weeks following the first
report many people were
mistaking stars for something unusual!12
A year later, I saw Ray Cecot give a presentation
at a local MUFON gathering:
- He said, that when he got to Stillwater
at 11 pm that first night (remember, the original report was
at 8 pm) the people gathered pointed at stars when asked
where the UFO was.
- But, Ray said he could not explain what they saw
earlier, and thinks it may have been something unusual.
Call me skeptical, even cynical, but at 11 pm the eyewitnesses to the
Stillwater UFOs demonstrated in no uncertain terms that they could not
tell the difference between an interstellar spacecraft, and a bright
star. Why should I believe they had that ability at 8 pm?
What about the ``dime sized objects?'' How do we go from stars,
to a dozen dimes?
It is important to note that people are very poor at judging
size and distance without good visual cues:
- If we know the size, we can judge (or calculate) the distance.
- If we know the distance (for example, if it is in front of a hill,
not above it, but in front) we can judge it's size or calculate
it's maximum size.
- But if we know neither of these two values,
we cannot judge either of them.
- And in the absence of more information, a brighter object
will be perceived and remembered as being bigger than a dimmer
I had asked you earlier how you thought a dime measured against the size
of the full moon. If you held a dime at arms length, how big would it
appear if held up against the moon? Think about this again, before
- Would the moon be larger than the dime? 10 times larger than the dime?
Would it be 100 times larger then the dime? This is the largest
estimate I've heard so far.
- In actuality, the dime would be 4 times the area
of the full moon (larger if your arms are shorter than about 22
inches). A typical frozen pea, held at arms length, is about the size
of the full moon.
- What would a dozen objects, each appearing 4 times the size of the full
moon look like? I would expect 911 lines to be ringing off the hook.
- I suspect what happened (this is a guess, I of course
cannot know---I wasn't there and enough data has not been offered),
is that in the excitement a plane or two were confused with the original
object. Or, over the course of observation, the witnesses lost sight of
the original object, and picked up on others, perhaps a fireball or a
- When asked about the objects' size, they answer what they
believe to be the honest truth, that it was
bigger than a star---perhaps the size of a dime---without realizing
just how big that is.
- What we do know is that according to the local MUFON director at
that time, by 11 o'clock that night they were looking at stars.
- And, we do know that by the following evening, the same people
were looking at a bright celestial object, as shown
by the steady image in the tripod mounted television news cameras.
Summary and Conclusions (Disclaimer II).
I started this talk with a disclaimer and I will end with a disclaimer.
The truth be told, neither I nor anybody else knows what the unnamed
women, her daughter and seven neighbors saw at 8 pm from Stillwater NY.
It could have been a distant jet, a bright star seen through clear,
cooling skies (the observing conditions at the time). The star or
planet could have been augmented by the autokinetic effect (as seemed
evident from the network news report), or some combination of these and
And who knows, it could have been an interstellar craft. The
evidence, however, hardly supports such an extraordinary
hypothesis---especially when simple, alternative explanations, employing
well-understood phenomena, are available.
The Stillwater event, however, when combined with the media coverage,
spun off its own mini-wave of UFO reports. It was not as big or dramatic
as the current Mexican wave, to be sure. But like the Mexican wave, the
stories have became more elaborate with time. Attendance at student
sponsored UFO symposium at Rensselaer Polytechnic Institute was high.
(Although, it is interesting to note, very few of the attendees were
students.) And, this included the usual collection of drawings of UFOs,
pictures of crop circles, support groups for abduction victims, etc.
Most of these people, no doubt, were already believers and all the local
flap did was give them a booster shot. However, many people within the
WRGB and WTEN listening areas now know that something, maybe
an alien spacecraft, was seen in Stillwater, since no additional followup
was offered in newspapers or on TV. The evidence, however,
simply doesn't support this claim.
Instead, the evidence is consistent with misperception of celestial
objects, augmented by the autokinetic effect and possibly other
illusions of motion and recall. It is possible for ordinary people
to see something unfamiliar, and even exciting and extraordinary,
in the night sky. That doesn't mean what they saw is inexplicable,
or even unusual. On the contrary, it may be the familiar night sky,
viewed by people not so familiar with it, augmented by some popular
images of flying saucers and aliens.
the Fermi paradox. That is, a civilization that advanced should have
contacted us by now. For a good review of the Fermi paradox see
Zuckerman, B. and Hart, M.H., Extraterrestrials: Where are They?,
Second edition, Cambridge University Press, 1982/1985, and Dick, S.J.,
The Biological Universe: The Twentieth-Century Extraterrestrial
Life Debate and the Limits of Science, Cambridge University Press,
Which damages credibly, IMHO
Hence, it is also called the ``keyhole''
Goldstein, E.B., Sensation and Perception,
Wadsworth Publishing Company, 1980, pp. 265--266 (or any
introductory perception book), George, L., Alternate
Realities: The Paranormal, The Mystic and the Transcendent in
Human Experience, Facts On File, 1995, p. 27.
(Sherif, M., A study of some social factors in
perception, Archives of Psychology, 27, pp. 311--328, 1935).
Sherif, M., An experimental approach to the study of attitudes, Sociometry, 1, 1937, pp. 90-98.
Sherif was Turkish,
and he noticed people kept moving away from him as he talked.
A thorough summary of the
autokinetic literature in social psychology can be found in
Carolyn Wood Sherif, Orientation in Social Psychology,
Harper & Row, New York, 1976. George, Alternate
Realities, contains entries for autokinetic effect, and for
group dynamics of unusual experiences.
early work on memory and recall is summarized in: Loftus, E.F., Eyewitness Testimony, Harvard University Press, 1979. Information
about reconstructive recall in a variety of natural settings is in
Neisser, U., Memory Observed: Remembering in Natural Context,
W.H. Freeman and Company, 1892.
Fuller, J.G., Incident at
Exeter, Putnam, 1966; paperback, Berkeley, 1974.
The UFO Verdict: Examining The Evidence, Prometheus,
1986, pp. 111--119. The fit was not statistically significant,
nor could it be with such a small sample size. Sheaffer discusses
other evidence that the Exeter UFOs were celestial bodies, such
as a correlation with cloud cover, regular nightly appearances
that shift according to sidereal time, and descriptions of the
object consistent with celestial bodies known to be visible at
It is interesting to note that in the definitive work supporting
one of the best documented UFO cases, only 7 observations out
of nearly 100 occurring over 5 months were written
up with enough accuracy to tell both approximate direction
and date of observation.
Elders, Lee., and Jaime Maussan, Messengers of Destiny, Genesis III Productions, narrated by
Brit and Lee Elders.
French, A. The Why-Files, December 1994.