It should be noted that the report did not state that the hypothesis of extraterrestrial visitation had been conclusively disproved, only that the evidence accumulated up to that time in relation to the issue had contributed nothing to science and showed no sign of contributing anything in the future.

How well has that conclusion stood the test of time?

Examine the sighting report that Richard Dolan (Commentary 1) regards as typical and informative. The report was submitted to the National UFO Reporting Center in 1999 and refers to an event that allegedly occurred in 1976 near Hydes, Maryland:

it was dusk that day. we saw this round craft come out of the northeast over the horizon. it was slowly rotating counter clockwise. white lights only, were on the outer edges. it moved slowly, maybe 30 to 40 miles per hour. it came directly over us. we were on a horse farm, laying on the front lawn just after dinner. this craft was just below the sunlight that was left in the sky. we could not see any details. when it came over us, it stopped. then separated into four smaller craft. then at the blink of an eye, they shot over the horizon. each ship went directly north, south, east and west respectively. there was absolutely no sound from this craft. we learned the next day that there were sightings over peachbottom atomic plant that day. the same direction that our craft came from. to this day, we have never spoken about this to anyone, not even between ourselves. there were 6 of us. two music teachers, a medical lab tech, a texas instruments tech, police officer, a kindergarten teacher.

As scientific evidence, this statement has numerous “red flags” hanging all over it. The writer, supposedly a professional, seems not to want to bother with the standard capitalization rules for English sentences. The statement is only semi-coherent, with sentences describing various aspects of the incident tumbling over each other in a rush; with 23 years to think about the incident, it ought to have been possible to organize the description into a coherent narrative. (S)he reports that no details of the object could be seen, yet states that it was 1000 feet in diameter and traveling 30 or 40 miles per hour. How these size and speed determinations were made is unspecified, nor is there an explanation for an inability to resolve details when it was possible to determine size and speed. Accepting the size and speed estimates leads to another problem. Hydes, Maryland is located near a number of heavily-traveled highways and air transportation corridors. Near-by observers should have numbered in the thousands and generated numerous newspaper headlines; we are referred, instead, to some alleged sightings at a nuclear power plant located a considerable distance away.

Mr. Dolan informs us that this kind of report is typical. He’s quite right; it is typical, but as scientific evidence it’s worthless. Individuals and organizations adhering to the notion of ET visitation accumulate reports like this by the thousands and periodically present them to the public to support their position. There’s a logical fallacy at work in this constant piling-up of reports, the fallacy that large amounts of bad evidence somehow add up to good evidence. They don’t. You can’t make a silk purse out of a sow’s ear, nor can you make one out of 10,000 sow’s ears. The Colorado investigators were right; despite their volume, reports such as this, which had contributed nothing to science as of 1968, have yet to contribute anything in the intervening 33 years.

The fact that Mr. Dolen gives credence to this flawed statement illustrates an aspect of the UFO issue that ought to trouble proponents of the notion that this issue is a serious scientific problem. We refer to an apparent unwillingness, on the part of far too many of these proponents, to apply even a modicum of critical thinking to such reports.

One of us (Scott) recently attended a UFO conference. At this event, a physicist widely considered to be a technically adept investigator (who shall remain nameless) gave a presentation in which he described his analysis of photos showing peculiar lights over the night skyline of an Arizona city. He showed the audience how he had compared the lights of the city in the two different photos that the witness claimed had been taken only a few moments apart. There was no question that the city lights had changed markedly. Test photos taken for comparison showed that one was taken sometime before 11 PM and the other taken sometime afterwards, despite the witness’s claim that both were taken in quick succession at about 8 PM. (At about 11 PM, skyline lighting changes significantly as businesses and homes turn off their lights for the night.) The investigator then asked the witness for the photographic negatives. He learned that the two photos were actually from different rolls of film, separated by several other frames, some showing only the skyline, some showing only the peculiar “UFO” lights (This aspect of the report is striking in its resemblance to the Colorado report’s Case #7.

At this point, a listener to the talk might have expected the investigator to conclude that this was not a reliable case to proceed with. The witness’s story did not jibe with the photographic facts, and the contents of the interim photos suggested experiments in trick photography. But the listener would have been wrong. The investigator touted this as “missing time discovered through photo analysis” (For the uninitiated, the “missing time” phenomenon is a standard component of alien abduction stories; it occurs when someone notices that the time on a clock or watch is considerably later than expected; the abduction event that supposedly occupied this time is somehow erased from memory.)

When questioned as to his conclusions, the investigator stressed that “…the witness is a very credible, respected member of her community. She would not have lied about it.” Apparently this investigator had never read Colorado case 7; that hoaxer was a retired military officer with an “irreproachable” reputation. The investigator also apparently never heard of Occam’s Razor, the principle which states that, other factors being equal, one chooses the simpler of two competing explanations for an observation.

When one is investigating a UFO incident in the expectation that it might provide evidence that our planet is being visited by ET’s (a most extraordinary hypothesis), a high level of critical thinking should be strenuously applied. But in the two examples of “pro-UFO” evidence seen here, this does not appear to be happening. Mr. Dolen supports the flawed statement quoted above, and the audience at the conference was generally accepting of this perfectly ludicrous photo analysis. Acceptance and support of this kind of thing by adherents of the “pro” viewpoint, as if it were serious science, leads the skeptic to wonder, “If this is the good, credible evidence, what does the bad, non-credible stuff look like?”

Actually the two kinds look very similar, because the UFO issue can no longer (post Colorado report) make a strong claim to being a scientific issue at all. It shows, instead, numerous signs of being a social phenomenon, driven by the print and electronic media, and there is strong evidence that this has been the case all along.

Go back to the beginning, to the Kenneth Arnold sighting. The phenomenon described by Arnold was a group of boomerang-shaped objects that moved like saucers skimming across a water surface. But the report was garbled in initial press reports, leading readers to believe that the alleged objects were saucer-shaped. Subsequent reports, amplified by cinema and television, spread the “saucer” or “disc” image of UFOs to people all over the world. And while many different shapes have been reported for UFOs over the years, the majority of reports have been of saucers or discs, a clear indication that witnesses are seeing what they expect to see, and reporting what others accept as the norm.

There is also compelling evidence that the appearance of UFO occupants, as widely accepted among “contact” adherents, arose out of a particular episode of a television series. Barney Hill, who was allegedly abducted by beings from a UFO in the early 1960s (the initial case of this type), went into therapy and was hypnotized in the course of his treatment. Under hypnosis, Hill described the eyes of his abductors as “speaking.” This peculiar phrase had been used by an extraterrestrial character in an episode of the ABC-TV series “The Outer Limits,” which had aired only days before Hill’s hypnosis session. The episode was “The Bellero Shield;” the alien portrayed was bald, essentially featureless in face and body, and had swept-back eyes, just as Hill sketched under hypnosis. Although other early reports of UFO occupants varied significantly from Hill’s (probably inspired by other stereotypical alien images), his description is the one that has saturated popular culture via the media.

In 1975, NBC-TV broadcast a dramatization of Hill’s experience in a made- for-TV film called “The UFO Incident.” Many millions of people watched this allegedly true story and learned what aliens are supposed to look like. A couple of years later, Steven Spielberg’s “Close Encounters of the Third Kind” became one of the most popular motion pictures ever made, depicting beings similar to those in Hill’s description. Public perception of the “standard model” alien was further influenced by the cover of the 1987 best- selling book “Communion,” an allegedly true account of alien contact, which sported the expected image. Had Barney Hill’s hypnosis session taken place earlier, or had the ABC network scheduled the “Bellero Shield” later, we would in all likelihood have a different “standard model” alien.

Let’s go on to another kind of evidence, one that is piling up into a rather convincing accumulation. That’s the evidence relating to the impossibility of reported UFO behavior under limitations imposed on us by a number of well-tested physical principles. The scientific consensus on these limitations has become more solid over time, making the notion that our planet is being visited by ET spacecraft less and less convincing. (We’re assuming here that our hypothetical ET’s are conceptualized as physical beings traveling in physical machines from place to place in the here-and-now universe that we see around us. Concepts of “light beings”, “interdimensional portals”, or “higher vibratory planes” we relegate to the realm of the pseudomystical.)

Crudely stated, the limitations that concern us are:

1. No object travels faster than light (the Einstein speed limit).

2. No object can be made to move without forcing some other object to move in the opposite direction (Newton’s 3rd law of motion).

3. No object can move through the atmosphere at bullet-like speeds without creating a sonic boom (a direct consequence of the Doppler effect).

4. Gravity pulls; it can’t be made to push.

5. Complex living beings don’t survive instantaneous accelerations from a standing start to thousands of miles per hour, nor do they survive instantaneous sharp turns at those speeds (direct consequences of inertia).

Referring to limitation #1, there can be little doubt that if ET’s are visiting our planet, they would have to do so in vessels traveling faster than light; sub-light “generation ships” would in all likelihood be totally impractical (more on that idea below). But the Einstein speed limit says this can’t be done, so we have to ask: How well-settled is the idea that nothing travels faster than light? Very well indeed, actually, and getting better established all the time. Back in 1947 when the UFO issue first came to prominence, relativity and Dr. Einstein’s speed limit were only about 50 years old, and only a handful of experiments had been performed to test their validity. Since then, we’ve educated several new generations of physicists, many of whom have worked at “pushing the envelope” of relativity. Experiments and theoretical studies have proliferated over this time, but unfortunately no exception has been found to this fundamental limiting principle of physics. In fact, there’s not even a realistic hint pointing to the possibility of an exception.

A counter to this argument is the claim that maybe we don’t know all the physics there is to know. Of course we don’t. But we do know a lot, and for almost a century now the evidence has been accumulating that the Einstein speed limit is both intractable and permanent. Anyone who holds that the limit might be bypassed by some “new physics” at some time in the future, or that ET’s may already have developed that physics, has a very heavy and rapidly growing burden of proof to bear; solid and convincing evidence, not speculation, is required to support that burden.

Moving on to the other limitations, it should be noted that these all apply to the standard kinds of behaviors reported for UFOs in the atmosphere. These behaviors include:

1. Instantaneous or near-instantaneous accelerations and decelerations between a dead stop and hypersonic speeds,

2. Instantaneous turns at those hypersonic speeds,

3. Absence of the expected sonic booms from these maneuvers, and

4. Absence of the expected visible indicators of a super-powerful propulsion system at work (smoke, noise, exhaust blast, etc.).

If we assume that some kind of “mothership” brought these craft here across the gulfs of space, and that this mothership complies with the Einstein speed limit (requiring decades or centuries to make the journey), this assumption avoids limitation #1. Unfortunately it won’t avoid the other four. To do that, we need such “Star Trek” notions as impulse drive, inertial damping, or anti-gravity. And these are contradicted by ideas that are, if anything, even better-established than the Einstein speed limit, as they are rooted in nearly 400 years of classical physics.

What we have, then, is a situation where the “pro” evidence consists almost entirely of statements from witnesses who have observed unusual phenomena in the sky and cannot identify what they saw, and whose perceptions and interpretations have been contaminated by images from the popular culture, while the “con” evidence (or at least the strongest such evidence) is a body of physical laws supported by massive amounts of experimental data.

Concerning the “pro” evidence, we know from numerous investigations of those witness accounts that a substantial majority of them (or practically all, depending on your source of information) are explainable as a mix of mundane phenomena observed under odd circumstances, plus a number of hoaxes. As noted above, the Colorado report is enlightening on these points. Taking the case studies as a whole, it is difficult to escape the conclusion that a witness observing something unusual, even a “trained observer,” has a near-zero ability to interpret that observation correctly and describe it accurately. It is also difficult to escape the conclusion that reliable individuals, pillars of the community with solid reputations for integrity, pull off UFO hoaxes with surprising frequency.

Concerning the “con” evidence, it needs to be emphasized that the various physical principles in question are approximately 100 to 400 years old, supported by enormous numbers of repeatable experiments and instrumented observations, all subjected to intense scrutiny by generations of scientific professionals who would like nothing better than to demolish an important pillar of the scientific edifice. And these ideas are not just textbook material. Our real-world technology abounds with applications of these ideas, all developed by engineers and inventors who must cope on a daily basis with the inconvenient limitations imposed on them by the physical world and its laws. Aeronautical engineers would be delighted if they could make gravity push rather than pull; inconveniences such as wings and fuel-guzzling engines on airplanes could be dispensed with. The designers of communications equipment and computers would be equally delighted to learn that Dr. Einstein’s speed limit could be violated; the possibilities would be dazzling. But alas, none of this is happening, and as the evidence accumulates it appears more likely than ever that it cannot happen, on this planet or any other.

In closing, a final point: The arguments made here are not conclusive. We cannot say with certainty that our planet is not being visited. We can, however, note that those who support the idea of ET visitation have always had a heavy burden of proof, a burden that has only grown heavier as time has passed. We skeptics, who find this idea implausible, have a lighter burden, and it gets lighter with time.