WHEN IT COMES to space, seeing is not necessarily believing.
Consider the photo that landed on my desk the other day. At first it looks like one of the standard Mars shots that NASA has been posting online for more than a month now.
It shows the front of the Spirit rover in the foreground and the now-famous ruddy, rock-strewn Martian landscape. But look a bit further into the distance and you'll see them - a Starbucks and a McDonald's arch, looking quite at home.
A friend who found the photo on the Web passed a print on to me, and it generated quite a few laughs at the office - along with some dark oaths from photographers to the effect that this kind of junk is why people don't believe the pictures they see anymore.
Meanwhile, there's nothing like a torrent of legitimate photos from space to bring out the UFO freaks, conspiracy theorists and fanatics who claim to see ancient cities, faces and religious images in pictures of the Martian surface and faraway galaxies.
You can blame the fake stuff on digital photography, which records images as a grid of tiny, colored dots stored on a computer's hard drive. The technology has spawned software that can manipulate images in ways that are invisible to the naked eye.
You may have already done this yourself. Virtually all photo-editing programs come with a feature that "removes" red-eye from flash exposures and changes the eye color to something resembling reality.
Microsoft's Picture It!, which I use frequently, has a wonderful little feature called "fix blemishes." Put the cursor on a pimple, wart, scar or shaving nick, click the button, and it disappears. I call it "digital Clearasil."
And those are just basic tools. With the advanced features available in many programs, it's not surprising that images from space have been tempting targets for pranksters, most of whom use their talent - such as it is - to create visual puns and wordless satire on contemporary life.
After I saw the first picture, I did a Google search and found a half-dozen silly Mars shots, all of which took NASA photos and superimposed images of Starbucks, McDonald's and Wal-Marts. Obviously many minds think along the same lines.
With one exception, they were obviously "PhotoShopped," a term photographers have invented for images edited with Adobe's popular and powerful software. But the best of the bunch, a Starbucks cup half buried in the Martian sand, was the work of a real expert.
On the other hand, there are folks out there who think NASA has already doctored the photos it posts, because - as we all know - the government is always hiding something. These are undoubtedly children of the people who knew for a fact that Neil Armstrong's walk on the moon back in 1969 was concocted on a Hollywood movie set. Just do a Google search for "fake Mars photos" and follow a few links that turn up. But buckle your seat belt before you click - you're entering the Twilight Zone.
More interesting, and just as entertaining, are folks who see strange things in photos from space. Skeptics have coined a term for this phenomenon - pareidolia, an illusion or misperception involving a vague or obscure stimulus that's perceived as something clear and distinct.
Pareidolia is common enough, and predates the space program by a millennium or two. We've all seen the Man in the Moon, or faces and images of ships and elephants in cloud formations (When I was a young reporter, I once wrote a story about a gardener who grew a green pepper that looked like Richard Nixon, but it never made the paper.)
In 1978, some 8,000 people made pilgrimages to the home of a New Mexico woman who discovered a picture of Jesus in a burned tortilla. And in 2001, thousands saw the face of Satan captured in a CNN video and Associated Press photos of smoke billowing from the World Trade Center. (For a great collection these and more example of pareidolia, visit http://thefolk lorist.com)
Space seems to hold a particular fascination for pareidoliacs. Some argue that the most famous was the distinguished American astronomer Percival Lowell, who in 1894 built one of the first modern observatories on a hill high above the clear air of Flagstaff, Ariz. His observations of Mars convinced him that its strange markings were "canals" built by an ancient civilization - a notion that persisted for more than half a century.
NASA disproved the canal theory beyond a doubt with its first Mars missions, but the agency's own photos - now available in quantity and high-resolution quality on the Web - have inspired similar flights of fancy in a wired world.
One of the most famous was the Hubble Space Telescope's spectacular 1995 photo of the Eagle Nebula - 7,000 light-years from Earth - where many of the faithful discovered what appeared to be an image of Jesus.
Cheryl Gundy, spokeswoman for the Space Telescope Institute in Baltimore, remembers that one well. "We certainly didn't go out of our way in captions to say it was the face of God," she said.
But she agreed that these things are in the eye of the beholder. "I think if you look hard enough and you want to see it, you will see it," she said.
At http://hubblesite.org/news center/newsdesk/archive/releases/1995/44/ you'll find the original photo.
Six years later, UFOlogists got their hopes up when a photo snapped by NASA's Solar and Heliospheric Observatory picked up what appeared to be a flying saucer. It turned out to be a digital artifact caused by stars in the background that blended into a single image.
Since the first Viking orbiter circled Mars in 1976, photos from NASA's space probes have provided grist for the Close Encounters mill.
If you're ready for another trip to the Twilight Zone, you'll find a good collection of them at www.icidal.com/xproject/news/marslife.html
The most famous was a low-resolution Mars image from 1976 that appeared to show the face of a king or lion carved into a plateau on the Cydonia Mensae. Speculation about the source of the face kept the ancient-civilizations crowd exercised for 25 years, until Mars Global Surveyor took a definitive pass over the site with a high-resolution camera and proved it was a natural rock formation.
Now that NASA has a couple of rovers on the planet (with more planned), we're likely to see many more mysteries resolved with equally prosaic explanations.
But somehow, it's a shame.