Mars Fever

Our vision of distant worlds has improved immensely since Gali­leo first pointed his slender spyglass at the night sky. Observational astronomy has moved from naked-eye observing to the use of large-format CCDs. These devices register an image by converting incoming light first into electrons and then into an electrical cur­rent, and astronomers typically gather light for several minutes up to an hour before reading out the device and inspecting the image. The CCDs that astronomers use are just larger format versions of the ubiquitous detectors found in digital cameras and cell phones. However, before photography matured, the only detector in as­tronomy was the unaided eye, and the only way to record an image was to sketch it on paper. Professional and amateur astronomers are familiar with “seeing,” the rapid fluctuation of images caused by convective motions in the atmosphere; it’s the phenomenon that causes stars to “twinkle.” Viewed through a telescope, star images flicker and dance. But there are moments of stillness when the im­ages become crisp.15 Observers ever since the time of Galileo have learned to swiftly record the view when the seeing is at its best. In those moments when the light is not quite as scrambled by the atmosphere, features become apparent that are otherwise invisible and images seem to snap into focus.

In 1877, Mars was at its closest approach to the Earth, and Giovanni Schiaparelli was prepared to make the best observations of Mars yet. Already a talented observer, he used his skills as a draughtsman to make rapid sketches of the planet during the mo­ments of sharp viewing, and he built up the stamina needed to concentrate intensely in short bursts through a long winter’s night. He made detailed maps, naming features as “seas,” not because he thought they actually contained water, but by tradition, as had been done with lunar features since the time of Galileo. He saw linear features stretching for hundreds of miles across the surface that were evocative of artificial constructions, although he resisted drawing this conclusion (figure 2.1).16 Meanwhile, a separate de­bate raged over whether the atmosphere of Mars contained a sig­nificant amount of water vapor. Some observers claimed that it did, but it’s very difficult to separate the signature of water around a remote planet from the very much stronger signature of water imprinted on the light by the Earth’s atmosphere, and these obser­vations turned out to be flawed.17 As an Italian, Schiaparelli used the term canali, which was once again given an erroneous and literal translation in English-speaking media.

Mars fever began to take hold. The Suez Canal had opened in 1869, so the public was primed to appreciate the engineering achievement implied by canals on Mars. Not every observer could confirm the linear markings, but many of them deferred to Schia­parelli’s skill and assumed that their own shortcomings were the obstacle. Amateur astronomer and author William Sheehan has noted the power of this type of thinking, where expectation and projection can shape the sensory experience: “Schiaparelli had taught observers how to see the planet, and eventually it was im­possible to see it any other way. Expectation created illusion.”18

The scene then shifted to northern Arizona. It was 1894, and Percival Lowell was driving his workers hard. He was racing to build a telescope before a particularly close approach of Mars. The patrician Bostonian had left his gilded life to fuel a personal obsession in the thin air of the northern Arizona desert. The previ­ous Christmas, Lowell had been given a copy of The Planet Mars by Camille Flammarion as a present—Flammarion was a noted French astronomer and popularizer of science, considered by many the early predecessor of Carl Sagan. Flammarion accepted the in­terpretation that Martian canals represented intelligent life and in his book wrote: “The actual conditions on Mars are such that it would be wrong to deny that it could be inhabited by human spe­cies whose intelligence and methods of action could be far superior to our own. Neither can we deny that they could have straightened the original rivers and built up a system of canals with the idea of producing a planet-wide circulation system.”19 Lowell had a prior

interest in astronomy and he correctly judged that the best place to see sharp images was in the high and dry desert air, far from any city lights. The Lowell family motto was “seize your opportu­nity” and Percival took it to heart, dropping his plans of leisurely travel in Asia to venture into the rugged terrain south of the Grand Canyon.

For fifteen years, Lowell studied Mars diligently and produced a series of drawings of intricate surface markings as he perceived them. To Lowell, the canals were real and they were manifestly artificial. Around his observations he wove a story of a dying race, more intelligent than humans, who had built a network of canals to carry water from the poles to the arid equatorial regions.20 Pro­fessional astronomers were skeptical of the observations and their interpretation, and were generally dismissive of the back story, but Lowell bypassed them with popular books and extensive lectur­ing. Lowell published his first book on the subject in 1896, titled simply Mars. Two years later, H. G. Wells incorporated major ele­ments of Lowell’s view of Mars into The War of the Worlds, which was very popular and struck a nerve with the public. The War of the Worlds was first published in magazine serial form, in the tradition of the novels of Charles Dickens. As a book, it has never been out of print and has so far spawned five movies, a TV series, and numerous imitators. At this point, cultural and scientific views of Mars were closely twined.

Lowell’s 1906 book Mars and Its Canals met with a strong re­buttal from Alfred Russel Wallace, co-discoverer of the theory of natural selection, who argued that Mars was far too cold to host liquid water. He considered that the polar caps were made of fro­zen carbon dioxide, not water ice, and he concluded that Mars was uninhabited and uninhabitable. Wallace’s critique made no differ­ence in the cultural arena. Ten years later, Edgar Rice Burroughs published A Princess of Mars, set on a version of the red planet alive with exotic animals, fierce warriors, and princesses in near­human form. He wrote another ten Mars stories over the follow­ing thirty years, inspiring Arthur C. Clarke and Ray Bradbury and launching a grand tradition of Mars science fiction.21

Mars fever was resistant to the medicine of improved astronom­ical observations.22 Lowell stubbornly defended his position until the end of his life, saying in 1916: “Since the theory of intelligent life on the planet was first enunciated twenty-one years ago, every new fact discovered has been found to be accordant with it. Not a single thing has been detected which it does not explain. This is re­ally a remarkable record for a theory. It has, of course, met the fate of any new idea, which has both the fortune and the misfortune to be ahead of the times and has risen above it. New facts have but buttressed the old, while every year adds to the number of those who have seen the evidence for themselves.”23 By 1938, telescopic remote sensing had demonstrated beyond any reasonable doubt that Mars was a dry, barren, lifeless desert, but that didn’t dim the twinkle in Orson Welles’s eye as he reeled the public in with his artful hoax.

The fever cooled dramatically in 1965 with Mariner 4. Spurred into existence by a series of firsts for the Soviets in space, NASA was a young government agency with ambitious plans. By the mid – 1960s the hardware development for the Apollo program was in full swing, but NASA also wanted to gain the initiative in inter­planetary probes.24 The Mariner series of space probes was de­signed to investigate the inner Solar System. Space exploration was definitely not for the faint of heart; in the 1960s roughly half of NASA’s probes failed. Mariners 1 and 2 were intended for Venus. Mariner 1 veered off-course and had to be destroyed just after launch, while Mariner 2 made it to Venus and transmitted useful data as it flew by. Venus was known to have thick, opaque clouds so there was no camera on board. Mariners 3 and 4 were intended for Mars. Mariner 3 mysteriously lost power eight hours after launch, so all eyes turned to Mariner 4.25 After seven months and 220 million kilometers of travel and one mid-course correction, it swooped within 10,000 kilometers of the planet’s surface.

The spacecraft sent back twenty-one black and white images, the first pictures ever taken of a world beyond the Moon by a space probe. The images were small and grainy, with eight times worse resolution and sixty times fewer pixels than a typical cell phone camera. They showed a barren and cratered surface. Other instruments indicated a sparse atmosphere, daytime high tempera­tures of -100°C, and no magnetic field that would be needed to protect the planet from harmful cosmic rays.26 Mars, so deeply rooted in the popular consciousness as a living world, seemed to be Moon-like and lifeless.