A satellite photograph has many people wondering whether the elusive Loch Ness monster might have been photographed from space.
The image seems to show a strange, ghostly oval shape with trailing white tendrils either on the surface, or just below the surface, of Scotland's famous Loch Ness. The images were taken years ago but re-surfaced last week when the story was picked up by British newspapers.
Monster-hunters debated the new evidence, but soon several websites debunked the "Nessie" photo, including www.southernfriedscience.com, DoubtfulNews.com and www.metabunk.org, which offered clear explanations for how the image was created. The conclusion: The image of the Loch Ness Monster is simply a boat wake. In fact the distinctive wake pattern exactly matches that created by other boats, both on Ness and in other lakes. The satellite image is not a single image, as many assume, but instead a composite of several different images, each with a different contrast; this helped create the illusion of a creature. [Rumor or Reality: The 10 Creatures of Cryptozoology]
So if the latest Loch Ness monster photo turned out to simply be a boat, why did it look so mysterious?
Why satellite images mislead
While early proclamations of Nessie having been found by a satellite have likely caused some red faces, we shouldn't be too quick to judge those who saw a monster where none existed. The idea that a satellite could capture an image of a giant monster is not far-fetched. Many lake monsters and sea serpents are reported to be 50 feet (15 meters) or longer, and surface regularly where they are seen.
If armchair investigators are up to the task, they could monitor monster-inhabited lakes such as Scotland's Loch Ness, Canada's Lake Okanagan and America's Lake Champlain using satellite technology. Monster buffs don't need to dip their toes into cold lakes or brave the wilderness to search for their quarry; they can scan a dozen square miles over a cup of hot coffee at their leisure. [Satellite Images: The 12 Strangest Sites on Google Earth]
In their book "Remote Sensing and Image Interpretation" (Wiley, 2007), authors Thomas Lillesand, Ralph Kiefer and Jonathan Chipman explain why satellite images can easily mislead the public: "Although most individuals have had substantial experience in interpreting 'conventional' photographs in their daily lives, the interpretation of aerial and space images often departs from everyday image interpretation in three important aspects: 1) the portrayal of features from an overhead, often unfamiliar, perspective; 2) the frequent use of wavelengths outside of the visible portion of the spectrum; and 3) the depiction of the Earth's surface at unfamiliar scales and resolutions."
Indeed, biologist Andrew David Thaler noted several of these issues in his Southern Fried Science blog about the latest Nessie photo: "Satellite images aren't taken in real time. The photographs in question were taken in January 2005 ... Satellites travel along an orbital path, taking pictures that are then stitched together [and] stitched photos aren't perfect. For example, if one picture has a boat that's totally washed out (like almost every boat is when photographed from space) and another picture is just blue water, then you'll be left with the ghostly blue outline of a boat, which is clearly visible on the 'Nessie' picture." Case closed.
This is, of course, not the first time that a strange satellite image has caused controversy.
In 2011, people reviewing images on Google Maps spotted a tangle of mysterious, connected white lines in the Chinese desert. The strange images spurred a furor on the Web, where amateur sleuths offered learned (and not-so-learned) opinions about their function, ranging from UFO landing strips to top-secret military bunkers. The lines were eventually identified as a grid used to calibrate Chinese spy satellites.
As satellite images become more common, these sorts of "mysterious" photographs will also likely become more common unless the public becomes more educated about satellite imagery. After all, only photographs that are ambiguous and mysterious enough will come to the public's attention. If a photograph is crystal clear and unambiguous, no one will pay attention to it, because its identity is obvious.
On the other hand if a photograph is too ambiguous, it is likely to be ignored or deleted as an obvious mistake of such poor quality that it's worthless — it's the same reason we don't see the worst photos that people take with their cellphones, because they're soon deleted. For an image to be "mysterious" it needs to fall into that Goldilocks zone of being just clear enough to give an idea of what it might be, but not clear enough to actually tell what it is.
Though there have been many Loch Ness monster hoaxes dating back decades, most reports of the mysterious aquatic beast are simply mistakes and misidentifications — and this Nessie satellite photo is only the latest.
Benjamin Radford is deputy editor of "Skeptical Inquirer" science magazine and author of seven books, including "Lake Monster Mysteries: Investigating the World's Most Elusive Creatures." His website is www.BenjaminRadford.com.
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