This week, the mainstream media is reporting an undersea radar image of a "saucer shaped" object on the seabed in Baltic Sea's Gulf of Bothnia, between Sweden and Finland. The discovery was made by Swedish oceanographers who say it's nearly 200 feet across and lies 300 feet down.
The same object caused a stir last summer when it was originally spotted.
These most recent reports have renewed a firestorm of news reports and blogs saying that scientists have found something resembling a "classic flying saucer," and that further investigation is needed. A sonar image of an "object of interest" (pictured above) shows what has an uncanny resemblance to Han Solo's starship the Millennium Falcon from the film "Star Wars."
The mystery was compounded later in the week by the report of a smaller disk-shaped object nearby. Both images are interpreted to show a rigid tail or drag marks more than 1000 feet-long. Some people have speculated these skid marks suggest that the object might have moved across the floor as it crashed.
It is a page straight out of Micheal Crighton's 1987 novel, "The Sphere." But to call the debris "UFO-like" is as laughably presumptive as calling automobile hubcaps "baby UFO-like."
Linking a murky unknown circular artifact to alien visitors is leap of faith wider than jumping the Grand Canyon. So are alternative suggestions that it is from the "lost continent" of Atlantis, a submerged version of a Stonehenge, or an opening to a hidden world inside Earth. Perhaps it's the mother of all manhole covers; or maybe it's Bigfoot's potty seat?
Speculation swirling around this report is simply the latest in decades-old stories of alien visitors falling out of the sky due to some terrible malfunction of their flying saucers.
The most celebrated example is the 1947 Roswell, New Mexico crash of a military balloon that has been spun up and hoaxed into a legend. Supposedly this was really a break-up of a flying saucer complete with little alien cadavers.
In classic pseudoscience tradition, Roswell "true believers" accuse the Government of hiding all the good stuff away -- presumably in an Indiana Jones-style warehouse. The Roswell story is so patently ridiculous in so many ways it has become a self-parody of UFO conspiracy theories.
Unless aliens are clumsier that the Three Stooges, it's unlikely that they would be able to travel for light-years only to botch it up in the few thousand final feet of altitude. To add insult to injury, a group of psychics recently claimed that they "remotely viewed" a crashed alien spaceship on the moon. Sheesh, even advanced alien technologies have inadequate quality control?
Over the past three decades there have been nearly 15 million commercial airline flights, but just a few dozen crashes. Do occasionally visiting aliens have a horrendously worse safety record? It's hard to believe they would have managed to get off of their home planet in one piece.
Hokey flying saucer snapshots aside, no one has any idea what an extraterrestrial vehicle would really look like. It would be like asking a Roman chariot driver to imagine what vehicles on the Appian Way would look like in the year 2000.
UFOs are commonly reported as saucer-shaped vehicles tens of feet across -- big enough to hold little green men pilots. But even something the size of a cruise liner would be incapable of interstellar travel given the propulsion requirements.
Therefore, if flying saucers are real, there must be a giant mothership hiding out somewhere in the solar system, or on a moonbase. And the Internet has no lack of supposed evidence for alien moon bases -- which NASA's Lunar Reconnaissance Orbiter has somehow missed.
That said, it's not totally impossible that extraterrestrials have reconnoitered our solar system. Their probes would likely be artificially intelligent and stealthy, and I think small and built around nanotechnology. But biological, mortal creatures probably cannot survive interstellar journeys. And even if they could, they wouldn't come here simply to do tasks a robot could do.
Alien probe reconnaissance would be done from space. Though a close-up look and sample collection on Earth might be inevitable. But the intelligent machines accomplishing this would not be the 1950s tail-fin style things in myriad faked UFO photos. They might have more of a kinship to our deep space probes.
There is one simple science lesson from the Baltic Sea artifact report. It's something you can use in everyday life -- called Occam's razor.
The 14th century logician and Franciscan friar William of Ockham postulated that when you have two competing theories to explain an observation, the simpler one is the most likely explanation.
That makes it extraordinarily improbable that the Baltic Sea object is something that fell from the stars. The simpler solution is that it's a geological formation or some sunken vessel. The circular shape certainly suggests a gun turret, as seen in the above photo of the turret on the Civil War's Monitor ironclad ship.
"The bottom of the sea is a vast unknown, so why shouldn't there be UFOs? I could believe it," gushed one blogger.
Unfortunately the time-honored principle of Occam's razor makes the universe boring to some folks, but a lot more rational.