Several years ago, amateur astronomers poring over photos taken by the HiRISE camera onboard NASA's Mars Reconnaissance Orbiter discovered what appeared to be a symmetrically upright geometrical object on the surface of Mars. Rectangular in shape, the object also cast a shadow. Life's Little Mysteries reports that the image was dubbed a "monolith" and the photo began making the rounds on the Internet and periodically is reborn virally, catching the attention of more and more people.
And with each successive round of viral exposure the Martian monolith is treated to a new round of speculation as to its nature and/or purpose.
Many of the more hopeful see it as a monolith in the tradition of Arthur C. Clarke's classic alien artifact in the novel and science fiction film classic 2001: A Space Odyssey, a sign of extraterrestrial intelligence and a marker indicating that there exists other intelligences in the universe. Some think it might be something left behind by a Martian civilization that once flourished on the Red Planet (or might still flourish as part of a subterranean civilization, life having been driven underground by some unknown phenomenon).
Others simply see it as an interesting anomaly but perhaps not anything artificial.
One such individual is research technician and mission planner at the Mars Space Flight Facility at Arizona State University Jonathan Hill, who told the Life's Little Mysteries website that it was just a familiarly-shaped boulder on Mars' surface. Nothing more.
Hill noted that a higher resolution camera would bear out his observation. "When your resolution is too low to fully resolve an object," he explained, "it tends to look rectangular because the pixels in the image are squares. Any curve will look like a series of straight lines if you reduce your resolution enough."
Hill, who studies and processes many of the images taken on NASA's Mars missions, also noted that the shadow seen stretching away from the rectangular object is exaggerated due to the position of the sun, which was low on the horizon when the photo was captured.
But seeing something that reminds the more imaginative of scenes from "2001: A Space Odyssey" and inspires individuals to dream of contact with extraterrestrials is not new to Martian photography.
In fact, a photo of what appeared to be a mile-long translucent worm or tunnel structure captured by the Mars Global Surveyor even stirred the imagination of the famed scientist and science fiction author himself. Clarke said in an interview with the Planetary Society before his death, "I'm still waiting for an explanation of that extraordinary glass worm on... [Mars]... How big is it? It's one of the most incredible images that's ever come from space and there have been no [official] comments on it whatsoever!"
There is also the mysterious "Face Of Mars," which has prompted ample speculation about alien artifacts and purposeful positioning by extraterrestrials to let humanity know that they are not alone. NASA's Viking Orbiter first photographed the now famous image in 1976 and ufologists, alien life enthusiasts, and conspiracy theorists have produced mountains of audio, video, and printed speculative pieces on the nature of the strange "face" rising up from Mars.
However, a close fly-by European Space Agency's Mars Express in 2006 revealed the object to be what looked like a natural massif rising up from a plain on the Red Planet.
Of course, the true believers are certain that such an explanation is part of a cover-up or that the image is exactly what it appears to be, a an artificially constructed face, time-weathered and worn.
As for the Martian monolith, Life's Little Mysteries points out that calling the image in the photo a "monolith" is appropriate. Monolith translated from the Latin means "one stone."
(photo credit: NASA)