Wednesday, December 10, 2008

Back to Basics: UFOs

As a Trekkie and a sceptic, I am frequently asked my opinion on UFOs. Here's a high-level overview of my position on the topic.

What are UFOs?

UFO stands for Unidentified Flying Object. It's a jargon term originally used by military radar operators as a place-holder name for anything they detected on their screens until it could be identified. Some detected objects were never conclusively identified, and were then logged simply as 'UFO'.

Around the time of the Roswell incident, the term found its way into popular usage, and took on a whole new meaning.

Roswell, New Mexico, is a small town near a military base that was used extensively for testing of new and secret military technology. Farmers and other residents in the area would, from time to time, see strange things in the sky (experimental military aircraft) or find unidentifiable debris littered on the ground (crashed experimental aircraft). One such incident happened in 1947.

A litany of blunderous military cover-ups trying to hide the true nature of the experimental technology, combined with the popularity of science fiction literature at the time, led to the birth of a modern myth: a crashed alien spacecraft.

This incident is widely regarded as the birth of the UFO craze. Reports of "flying saucers" became more frequent, and before long people started reporting that they had encountered actual alien life-forms, often being abducted by them, and subjected to medical experiments.

In the midst of all this, the term 'UFO' lost its original meaning, and became a popular term for 'alien spacecraft'. Radar operators, pilots and other people familiar with the term started using it in public to describe their own experiences, and it caught on.

Is there any truth to the claims?

This isn't an easy question to answer. In order to address it properly, we need to break it down into several distinct claims:

  1. Intelligent alien life-forms have developed a technology that allows them to travel across interstellar space and visit our planet.
  2. A lot of people have seen things in the sky that can only be alien spacecraft.
  3. Alien spacecraft have crashed or been shot down on Earth, and there is a government conspiracy to hide it.
  4. People are visited or abducted by aliens and subjected to experiments.

Let's look at them in that order.

Aliens Are Here

The prospect of interstellar travel is a very difficult one, as far as our understanding of the laws of nature can tell us. The problem is that the stars are very VERY far away.

The nearest star, Promixa Centauri, is about four light-years away. A light year is a measurement of distance, and tells us how far light travels in a year. Light travels very fast (about 300 000 000 meters per second), so that means Proxima is about 39 732 000 000 000 kilometers away. Far.

So, if you were traveling at the speed of light, it would take you about four years to get from Promixa Centauri to Earth. But what if nobody lives at Proxima? The rest of the stars in our neighborhood of the galaxy are dozens, if not hundreds of light-years away. That's a very long trip, at the speed of light.

But there's another problem. As far as we can tell, it doesn't seem to be possible to travel at the speed of light. Albert Einstein's Theory of Relativity tells us that the closer you get to the speed of light, the more massive you become, so the amount of energy needed to accelerate you increases exponentially. To move something the size of the space-shuttle even close to the speed of light would take more energy than the sun puts out in its entire lifetime. That's a lot of energy.

So interstellar travel is very VERY difficult. It's so difficult that from our point of view right now, it's effectively impossible to do. There may be other factors we don't yet know about that make it completely impossible.

However, as I said, all of that is based on our current picture of the universe. It's not preposterous to suppose that there might be intelligent people out there on other planets who have a superior understanding of physics, and have somehow found a way to get around all of that. It seems pretty unlikely, but we can't rule it out.

Okay, so, what's the bottom line? Could aliens be coming to visit us? Probably not, but it's not impossible.

Lights in the Sky

When people claim to have spotted a UFO, the evidence presented comes in two forms:
  1. Photographs and video footage.
  2. Eyewitness accounts.
If someone shows you a photograph, or even a video, of something strange in the sky, it's pretty much impossible to know what it is you're looking at. Sure, it could be a giant spacecraft. Or it could be a hubcap tied to a string. Or a cloud. Or a firefly. Or an aeroplane. Or a sophisticated CGI forgery. Even if the photograph seems to obviously present something that looks like an alien spacecraft, there's simply no way to know if that is, in fact, what is being presented.

It's unwise to underestimate hoaxers. They're clever, and have a vast array of tools at their disposal to create unbelievably realistic looking photos and footage.

Unfortunately, photographs and videos simply aren't strong evidence for the existence of alien spacecraft. At best they can show you that there was something weird in the sky that day, but often it can't even tell you that.

When it comes to looking at the sky and seeing strange things, on the surface it makes sense to take the word of people like pilots, air-traffic controllers, radar operators and other professionals who spend a lot of time dealing with airborne things. You would think that they would know what they're talking about.

The thing is, those sorts of people spend a lot less time actually looking at the sky than you might think. They probably know more about aeroplanes and air traffic than anyone else, but what do they really know about the sky? If they're not the experts, who is? Who spends more time actually looking at the sky than anyone else?

Amateur astronomers.

How many UFO sightings are reported by amateur astronomers? Very VERY few. This is because amateur astronomers have spent considerable amounts of time learning about strange atmospheric effects that can make the moon or the planet Venus look strange. They are trained to tell the difference between an aeroplane, a satellite and a meteorite. They're accustomed to being able to tell the size, distance and speed of an object, just by looking at it.

So things that, to most of us, would look odd or even inexplicable, are ordinary and mundane to those people who are accustomed to looking at the sky.

So when a policeman or other respected public official claims to have seen a strange light in the night sky, that he is positive was an alien spacecraft, he's not necessarily lying. He's probably just mistaken, because he wasn't able to accurately identify what he was looking at.

Alien Contact

The claims surrounding alien spacecraft crashes and the surrounding conspiracies sound convincing when they're explained by believers, but when you look at them in more detail, you see how little evidence there really is: none.

The quintessential example is the Roswell incident I mentioned earlier. Eyewitness reports give details of strange, unearthly materials that were recovered from the crash site. The military files on the incident were recently unclassified, including the wreckage. The so called "unearthly materials" were aluminium foil and balsa wood. It would be surprising to find that in the middle of nowhere, but but it's pretty mundane stuff. Even the eyewitness testimony is full of holes.

Based on a critical analysis, there doesn't appear to be any reason to doubt the military report on the incident. Unless you believe the conspiracy. 

That's the trouble with conspiracy theories. Any evidence against the claim (like the evidence produced by the military) is evidence for the conspiracy (in this case the assumption is that the military fabricated the "evidence" in order to cover up the "truth"). Conspiracy theories are unfalsifiable (they can't be proven wrong) and therefore we can't put much stock in them.

Of course we can't rule out the possibility that such a conspiracy may exist. But when you take into account the sheer number of people that would need to be in on it, it becomes a pretty unlikely possibility. Remember that four guys were in on Watergate and they couldn't keep that a secret.


This, to me, is a very interesting part of the whole UFO mythos. The claims are that some people are kidnapped, subjected to experiments (that are usually of a sexual nature) and then returned to where they were found.

The first real story of this nature was the Betty and Barney Hill story. I can't do a better analysis of that whole story than Brian Dunning did, so I suggest you go and read (or listen to) that before you continue here.

Go on, I'll wait.

Back? Cool.

More recent accounts seem to have a lot in common. For the most part they follow a script something like this:

I was lying bed when I suddenly heard a very strange sound. I found that I was completely paralysed, except for my eyes. I felt a presence in the room with me, and I saw several small people with grey skin and large black eyes. They lifted me up and took me to their spacecraft, where they probed me with strange looking instruments. I lost all sense of time.

They returned me to my bed. When the noise stopped, I regained the use of my limbs and they were gone.

Sounds terrifying, right? How is it possible that so many accounts are so similar? Surely something must be going here!

Well, yes there is. But it probably has nothing to do with alien abductions.

Hypnogogic hallucination, also known as sleep paralysis or a waking dream, is a fairly common and well documented phenomenon. Essentially it is when your brain wakes up, but your body is still asleep. It's a highly unstable state, and is often accompanied by audio, visual, olfactory and even tactile hallucinations - particularly in the form of a "presence", a grey form, a feeling of being pressed down, and awareness of paralysis and loud rushing noises.

The brain will struggle to interpret those hallucinations in terms of familiar frame of reference. In the past this resulted in myths arising like the Old Hag, vampires, chupacabras, ghosts and possibly the Tokoloshe. It seems that new cultural pervasiveness of UFO stories has lead many people to overlay the cultural image of the "grey alien" onto these hallucinations

Most people will experience sleep paralysis at least once in their lives. Some people suffer from it chronically. 

So we have two competing hypotheses here:

1. An intelligent race from possibly hundreds of light years away decline to make themselves known to us as a whole, but see no reason not to pick up people at random performing odd experiments on them, leaving no evidence behind.
2. A well documented and common (but not well understood by the public) neural malfunction.

Both of these explain the phenomenon equally well, but only one of them doesn't raise any additional questions, or require us to introduce exotic physics. Occam's Razor tells us which is more likely.


Right, so where does this leave us?

It seems to me that this can all be summed up as follows:

Although it's possible (even likely) that intelligent life forms exist elsewhere in the universe, it is exceedingly unlikely that they have ever visited Earth, and almost certainly aren't visiting us now. If they are, they're very VERY good at covering their tracks, as they haven't yet left a single piece of evidence.

As a Trekkie, I hope for and look forward to the day when we might make contact with an alien intelligence. But I think that we're far more likely to do so through the efforts of SETI than through anal probes.