Bad Astronomy: Misconceptions and Misuses Revealed, from Astrology to the Moon Landing "Hoax" - Philip Plait (2002)

Part IV. Artificial Intelligence

Chapter 20. Misidentified Flying Objects: UFOs and Illusions of the Mind and Eye

n February 11, 1997, at approximately 3:00 A.M. local time, I had a close encounter with a UFO. Actually, multiple UFOs.

I was in Florida with my family to attend a Space Shuttle launch. I had been working at Goddard Space Flight Center in Maryland for nearly two years, helping to calibrate a new camera that was to be placed on board the Hubble Space Telescope. All of us who had worked on the camera got passes to see the Shuttle launch in Florida, and we were all excited about seeing our camera lofted into space.

The launch was scheduled for 3:55 A.M. That's not the best time to appreciate the spectacle and fury of rocket launch, but the vagaries of orbital mechanics demanded such a liftoff. My mom volunteered to baby-sit our infant daughter Zoe, so my father, my wife, my nephew, and I made our way to Cape Canaveral around 1:00 A.M. We quickly found out that several thousand other people were also attending. Too excited to nap, my father and I wandered around talking to the other attendees. Many people had telescopes set up to watch the distant shuttle, proudly standing under the intense glare of multiple spotlights. To see it we had to peer across a long stretch of the Banana River that separates the cape from main land Florida. The cape is surrounded by water, and by wildlife. We actually saw a couple of alligators, which is a weird sight so close to such a technological marvel.

About an hour before the launch, I spotted some unusual lights in the night sky, a dozen or more, to the right of the launch pad from our viewpoint. They were perhaps at the same distance from us as the pad, about 10 kilometers (6 miles), although it was hard to tell. My father pointed out that they were moving, so we kept watching. The movement was very slow, as if they were hovering. I figured it was a group of distant spotting planes, but then remembered that NASA only uses one or two planes to sweep around the area. No other planes are allowed near the shuttle; it is jealously guarded by NASA for obvious reasons.

My next guess was birds, but these objects were glowing. Balloons? No, they were moving too quickly. No satellites group together like that. My excitement mounted, despite my more rational thoughts. What were they? As I watched, I noticed that they were moving together, but not in a straight line. They weaved slightly. That ruled out satellites and a host of other mechanical objects.

I refused to think of any ridiculous explanations involving anything, well, ridiculous. But what were these things? All I could see through binoculars were glowing dots.

Their flight path was taking them to my right as I continued to watch them through binoculars. Slowly, faintly, I could hear a noise they were making. It was eerie, odd, difficult to place. Then, suddenly, the noise got louder, and the objects in my binoculars resolved themselves. My mind and heart raced. I was seeing ...

a flock of ducks. As they flew by us they were just a few hundred meters away, and they were unmistakably terrestrial waterfowl. The noise we heard earlier was their quacking, muffled by distance, and their otherworldly glow was just the reflected light of the fleet of spotlights flooding the Shuttle pad. The ducks' weaving flight was obvious now, too. They appeared to be hovering when we first saw them because they were so far away and were heading roughly toward us.

I never allowed myself to think that they were truly UFOs, but what was that odd feeling in the pit of my stomach while I watched them, and why was I vaguely disappointed when we identified them as ducks? I laughed to my dad, maybe a little bit too loudly, and we resumed our vigil over the shuttle.

I learned two interesting lessons from this experience. Well, three: the first would be not to mistake ducks for alien spaceships. But the other two are a bit more profound. One is that there is a human need to believe in extraordinary things. Over the course of our lives we build a mental database of ordinary events. We see trees, airplanes, buildings, people we know, and we catalog them in our minds. When we see something that doesn't fit into the picture we have of life, it can be hard to categorize. It's easy to get excited by it, to wonder about it. Sometimes we wind up either identifying it as something we already know or setting up a new category for it.

This happens in science all the time. Say a scientist spots a new phenomenon. It might turn out to be something we already know about that is seen in a new way, or maybe it's something actually new that deserves study. But so far, with all the observations made by thousands or even millions of scientists, not a single phenomenon has ever been shown to be anything but natural, and certainly nothing appears to be guided by an intelligent hand not our own.

But the need to believe in such things is firmly planted in our collective psyche. There is something wondrous in seeing something we cannot explain. I like mysteries, for example, and I'll worry over them until I can solve them. I think there may be some hardwiring in our brains that almost demands us to want mystery in life. If everything were explained, where would the fun be? So even I, a hardheaded and skeptical scientist, once allowed myself to be momentarily swept up in a nonrational thought process.

The third lesson from my close encounter that night at Cape Canaveral is that even an astronomer with years of experience and training in identifying objects in the sky can make a mistake, even a silly one. Together with a series of unusual circumstances (the objects were glowing, they were distant, they were headed roughly toward me) it was possible and perhaps even easy to make a false conclusion, or at least skip over the correct one.

In my opinion, these two processes-a need for wonder, and an all-too-easy ability to be fooled-account for the vast majority of UFO sightings. I am not a social psychologist, so I don't want to ponder any further about the human desire to wonder. It's fun to think about it, but I am not qualified to analyze it other than as a layman.

But I am a scientist and an astronomer. So let's take a look at the visual and physical phenomenon of UFOs.

A lot of people claim to see strange things in the sky-moving lights, changing colors, objects that follow them. But let's think about this for a minute: how many people are really familiar with the sky? I have found that there are things that happen in the sky about which people are completely unaware. Many have no idea you can see planets and satellites with the naked eye. When I talk to the public about such optical phenomena as haloes around the Sun and sundogs (teardrop-shaped glowing patches in the sky that are caused by sunlight being bent by ice crystals in the air), the vast majority has never heard of them, let alone seen them.

If someone is not familiar with things that are in the sky all the time, how can they be sure they are seeing something unusual?

This is not as ridiculous as it sounds. Venus, for example, can be amazingly bright, far brighter than any starlike object in the sky-in fact, it's the third brightest object in the sky after the Sun and the Moon. Seen low on the horizon, Venus can flicker in brightness and change color as the atmosphere bends its light. If you are driving, it can appear to follow you through the trees.

It's common to mistake brightness for size. I receive e-mails from people all the time asking me about the huge object they saw in the sky, and it usually turns out to be Venus. This planet is so far away that to the unaided eye it looks like a star, although a bright one. Unless you have unusually sharp vision, without at least a pair of binoculars you can't see Venus as anything other than an unresolved dot. Yet, because of its tremendous radiance, Venus is commonly mistaken by people as a huge disk in the sky. That's why it accounts for the majority of UFO sightings.

If you are not familiar with the sky, any unusual object can make you jump to erroneous conclusions. But there is a group of people who are very familiar with the sky-by some estimates there are as many as 100,000 amateur astronomers in the United States alone-who spend many hours every week doing nothing but looking into the sky. They own telescopes and binoculars and spend every clear night outside looking up.

Think about that for a moment. These folks are looking at the sky all the time. Yet, of all the people I have had approach me or e-mail me to say they have seen a UFO, not one has been an amateur astronomer. As a matter of fact, I have never heard about any amateur astronomers seeing something in the sky they absolutely could not explain. Yet they spend far more time looking at the sky than lay people and statistically should see far more UFOs! How can this be?

Easy. Remember, the amateur astronomers study the sky. They know what's in it and what to expect. When they see a meteor, or Venus, or sunlight glinting off the solar panel of a satellite, they know it's not an alien spaceship. Amateur astronomers know better and, in fact, all the amateurs to whom I have spoken about this are very skeptical about UFOs being alien spaceships. This is a very strong argument that there are mundane explanations for the vast majority of UFO sightings.

Eyewitness accounts are notoriously unreliable. However, UFO enthusiasts usually point out that we have far more evidence than these accounts. We have cameras.

We have all seen footage of UFOs on television. Usually it's an amateur photographer, perhaps someone on vacation with a video camera, who sees a distant object and quickly gets it on tape.

I am always immediately suspicious of such sightings, specifically because of my own experience with the ducks. A blurry object seen from a great distance is a poor piece of evidence for extraterrestrial visitors. It could be any number of common things, from ducks to balloons. Airplanes headed straight at you can appear to hover for a long time (I once thought an airplane making an approach to an airport behind me was the planet Mars; it was stationary in the sky and glowing red). Helicopters actually can hover, and have odd lights on them. A shakily held camera makes the object appear to move. I have seen quite a few TV shows showing footage of a breathless videographer exclaiming how an object is moving, when it's obviously the unsteady hand of the person that is moving the camera.

Worse, the camera itself distorts the image. A famous UFO tape shows a faint dot that, as the camera zooms in, gets resolved as a diamond-shaped craft. Actually, the diamond shape was due to the internal mechanisms of the camera, and when the videographer zoomed in the object took this shape because it was out of focus.

Modern electronic cameras have all sorts of odd defects that can distort images in unfamiliar ways. Another famous series of shots shows UFOs that are very bright with a very dark spot trailing them. UFO believers claim that this is due to some sort of space drive using new physics we don't understand. Actually, this is more likely an effect in the camera's electronics. A bright object can cause a dark spot to appear next to it in the camera's detector due to the way the image is generated. I have seen similar effects in Hubble Space Telescope images.

My point is, don't attribute to spaceships what you can attribute to yourself or your equipment.

On the pseudodocumentary TV show Sightings, which gullibly and unskeptically presents all manner of pseudoscience as fact, I saw a segment in which a photographer claims that hundreds of UFOs can be seen all the time. He puts his camera directly underneath an awning and points it to just below the Sun. The awning shades the Sun just enough to put the camera in shadow. He then turns it on, and voila! You can see dozens of airborne objects flitting this way and that. He calls this method the "solar obliteration" technique, and says that without it we would never see the flying objects.

The photographer claimed that these were UFOs. I was amazed; he had nothing on tape but fluff blowing in the wind. He didn't bother performing even the simplest of tests to try to find out what these things were. If they were cottonwood seeds, for example (which is what they look like to me), a fan blowing near his camera might settle the issue. If that didn't work, he could set up two cameras spaced a few meters apart and aimed in the same direction. A distant object would appear in slightly different places in the cameras' fields of view. You can see this yourself by holding your thumb up at arm's length and looking at it first with one eye closed, and then the other. Your thumb will appear to move back and forth compared to more distant objects because the angle at which you are viewing it is changing. This method, called parallax, can be used to determine the distance to objects. Our intrepid UFO photographer never tried it, so we may never know if his objects were interstellar travelers or simply a tree trying to be fruitful and multiply.

Another thing to note when listening to UFO claims is the estimation of size and distance. This is always a red flag for me when I hear a UFO report. Someone says it is a kilometer across and twenty kilometers away, but how do they know it isn't a meter across, and twenty meters away? Without one measurement, you cannot possibly determine the other.

People who should know better make this mistake as well. Take Dr. Jack Kasher, for example. He is a physics teacher at the University of Nebraska at Omaha. He believes that UFOs are in fact spaceships populated by aliens. His claim to fame involves a bit of footage from STS 48, a Space Shuttle flight from 1991. During the mission the cameras were pointed down, toward the Earth. The cameras used at night are extremely sensitive and can see outlines of the continents, even in the dark.

In the now-famous footage, we see specks of light moving in the camera's field of view. Suddenly, there is a flash of light. One of the specks then makes a sharp-angled turn, and another shoots in from off-camera, going right through where the other speck was.

Kasher claims that this is evidence of alien spacecraft. The first point of light is an alien ship. The burst of light seen is the flare from a ground-based missile launch or a secret test of a Star Wars defense. The second point of light is the missile or beam weapon itself. The first dot, the alien ship, then makes an evasive maneuver to avoid being blown back to wherever it came from. According to Kasher, the film has captured an interplanetary battle.

Needless to say, I disagree with him.

So do a lot of other folks. These include Shuttle astronaut Ron Parise and space program analyst James Oberg. Both have discussed what really happened on STS 48. The specks of light are actually bits of ice floating near the Shuttle. The particles of ice form on the outside of the Shuttle on every mission, and can get jolted loose when the rockets fire. Once separated, they tend to float near the Shuttle. The flash of light seen was a vernier rocket, a small rocket that controls the direction in which the Shuttle points. It does not generate much thrust, which is why you don't suddenly see the Shuttle moving during the burst. (Kasher claimed that a rocket firing would obviously move the Shuttle but neglected to research just how much thrust the rocket gave off.) The rocket burst hitting the first bit of ice is what suddenly changes its course, and the second bit of light flashing by is simply another ice particle accelerated by the rocket. If you look at the footage closely, you can see it doesn't actually get very close to the first particle, making this a poor demonstration of Star Wars technology.

Kasher has made quite an industry of going on TV shows and showing this footage, which he clearly does not understand. He even sells a video of his analysis of the footage ($29.95 plus shipping and handling). I'd save my money if I were you.

I am commonly asked if I believe in life in space, and if aliens are visiting us. I always answer, "Yes, and no." This confuses people. How can I believe in aliens when I don't believe in UFOs?

It's actually easy. Space is vast, terribly vast. There are hundreds of billions of stars in our Galaxy, and it's becoming clear that many-if not most-have planets. There are billions of galaxies like ours in the universe. In my opinion, it's silly to think that in all the universe we are the only planet to have the right conditions for life to arise.

But even if the Galaxy is humming with life, don't expect ET to come here to poke at us, draw funny patterns in our corn fields, and mutilate our cattle. The very vastness of space makes that unlikely. Even with highly advanced technology, it would be a lot of work to explore every star and planet in the Milky Way. And if their technology is so advanced, how come they crashed here in Roswell in 1947? It seems unlikely that we would be able to shoot down a spaceship; that's like cows being able to take down a fighter plane. And if their technology is so advanced, why would they crash a few kilometers from the end of a journey that lasted for trillions of kilometers?

Many people assume that faster-than-light travel is possible. Although there is no real evidence for it, let's assume that travel through hyperspace, warpdrive, or some other method is feasible.

If that's true, and some alien race knows about it, where are they?

Our civilization has been around for a few thousand years, and we are starting to explore the near reaches of space. If we had faster-than-light travel, we could populate the entire Galaxy in just a few thousand years. Even with slower-than-light ships we could do it in a few million years at most.

That may sound like a long time, but not in the galactic sense. Elsewhere, a star like the Sun, only a few hundred million years older, might have had a booming civilization on one of its planets while trilobites swam in our own oceans. If this civilization decided to colonize the Galaxy, then by now the whole place should be filled with them.

Yet we have no proof they are here, so you have to assume that they have some sort of Prime Directive, as in Star Trek, to leave young civilizations alone. But then, why do we see so many of their spaceships? UFO enthusiasts want to have it both ways; they believe that incredibly advanced aliens come here in spaceships, yet these aliens are still so dumb that a bunch of primitives who barely understand atomic energy can photograph them ten times a day. That stretches credulity beyond the breaking point. I think the Truth Is Out There. It just isn't down here.

It frustrates me to see true believers claim that every light in the sky is an alien spaceship. However, it gives me pause when I remember that I was once fooled by a flock of ducks on a dark night at the most rational of locations, a rocket launch. It helps me remember that anyone can get fooled; I just wish that more people would be more critical about what they see.

As for that Shuttle launch, it was successful despite any fowl play. The camera was installed perfectly, and returned many gigabytes of interesting and useful information about what is really going on in space. And I will admit it here, in this book, for the first time: in some of those images I did see evidence of intelligent life in space. In many images from Hubble I have seen long, bright streaks of light that were clearly not cosmic ray tracks, misguided tracking, asteroids, comets, or moons.

What were they, then? They weren't alien spaceships. The long streaks were caused by human-built satellites, placed in orbits higher than Hubble. As they passed through Hubble's field of view, their motion left a streak of light.

We have met life in space, and it is us.