In 1976 the NASA Viking 1 robotic spacecraft arrived at Mars. The orbiting probe took many photos of the planet's surface, but there was one particular photo which caught the public's attention like no other. It was the mysterious "Face on Mars", and it sparked a frenzy of speculation which was to last two decades.
The photo, shown right, does look remarkably like a human face the size of a small mountain (it's about 3km from top to bottom). How did it get there? What could this mean?
Theories abounded, from ancient human space-traveling civilizations to monuments constructed by aliens. Many people claimed to see further details in the face such as a hairstyle. Others claimed that the surrounding terrain contained more mysterious features, including geometric patterns and additional monuments.
At the same time, conventional scientists seemed unusually quiet about the whole thing. Official papers were rare and NASA didn't show any signs of wanting to investigate further. This helped spawn a conspiracy theory that NASA was trying to cover up some startling discovery. The theory gained momentum throughout the 1980s and 1990s with a proliferation of articles, television documentaries and websites devoted to the subject.
To compound the problem, political support for Mars missions had dried up after Viking(1). NASA faced massive budget cuts and and it was to be a long wait before the red planet would be visited again. Conspiracy theorists argued that this turn of events was more about the secret of Mars than budget constraints.
Yet another blow came in the early 1990s when NASA launched the Mars Observer mission to take detailed photos of the martian surface. This mission was lost when a fuel-line ruptured on approach to Mars. Conspiracy theorists interpreted this as further evidence of a cover-up.
Finally, In 1997, Mars was visited by a successful NASA orbiter called Mars Global Surveyor (MGS). With its high-resolution camera it was able to photograph the face site in far greater detail. This much-anticipated event put a lot of pressure on NASA - so much so that it actually had an adverse impact on the mission(2). However the photo was taken in 1998 and the mystery was solved.
The face was shown to be a natural feature. Specifically, the face is a mesa - an isolated, relatively flat-topped hill or mountain. Mesas are quite common on Mars and appear in many places on Earth as well.
Due to mission constraints the 1998 photo was taken on a angle and wasn't perfect quality. The conspiracy theorists weren't satisfied and wanted more proof. They got it in April 2001 when MGS was directly over the face site. The clearest photo yet was taken and left absolutely no doubt about the natural structure of this feature. Further 3D models added even more evidence that the face effect was a fluke.
Original Viking Photo (1976)
Mars Global Surveyor Photo (2001)
Hi-Res Version (280KB)
Below: A computer-generated 3D perspective view of the face using laser altimeter data from MOLA (April 8, 2001). Credit: Jim Garvin (NASA) and Jim Frawley (Herring Bay Geophysics).
Below: The area the photo was taken in, known as Cydonia. As you can see, there are numerous similar land features to the "face".
The Face on Mars is a classic example of media-driven misperception. Even in the 1970s scientists were well aware of the geology of the Cydonia region and had no doubt the face was a natural feature. However, since there is no news value or money to be made announcing "Natural Feature Found on Mars!", popular media pushed the intrigue angle and the mythology blossomed.
It is interesting to ponder the effects of this saga on the genuine scientific goals of the space programme. Scientists complained bitterly about the media popularity of the face theory whilst genuine discoveries went unreported. Mars mission scientist William K. Hartman said in his excellent book A Traveler's Guide to Mars:
"You'd come home from a sensational scientific meeting about new spacecraft findings, Martian meteorites, and possible discovery of fossil microbes, then go to a cocktail party where, once they found out that you studied Mars, all that the people wanted to hear about was the Face on Mars."
There are two ways of looking at this. On one hand the public appetite for mystery and conspiracy theories was a distraction from more lofty scientific goals. One the other hand, this saga did fuel a lot of public interest in the Mars missions. Most people find it hard to get excited about analysing martian soil samples as they don't really understand the relevance, but a great mystery to be solved is a compelling attraction and something people can easily relate to.
So is it a good idea to tease the public with dubious mysteries in order to get them interested in genuine learning? In my opinion, it is not. In an ideal world the media would focus on the real excitement of genuine discovery and there would be no need to rely on false expectation. In addition, it becomes even more difficult to excite people about soil samples after building them up to expect an alien civilization.
Although the excitement created by the Face on Mars may have had some positive benefits, it is more desirable to promote interest in the honest truth than artificial hype.
Today people still wonder about the Face on Mars. Many are unaware that the mystery has been solved. In this case it seems the truth is somewhat less memorable than speculation.
(1) Apart from the photo of the face, the Viking mission revealed a desolate, apparently lifeless planet which was not what the public was hoping for. This was widely seen as a disappointment and the appeal of Mars was diminished. It was not until the Mars missions of the 1990s, which provided new information about the diverse nature of the planet, that public interest was rekindled.
(2) The Mars Global Surveyor mission was designed to take extensive photos of the planet surface in a systematic manner. NASA scientists were as keen as anyone to see the face but the mission plan meant that it would be a long time before the orbiter was in a position to take the photo. The public (and the media) couldn't understand the delay and accused NASA of stalling. In the end the pressure took its toll and NASA administrators ordered a reschedule so the photo could be acquired sooner. This was no small task - to change the mission plan so drastically required resources to be diverted from legitimate scientific goals.