Lowell’s reasoning went like this. Mars is habitable, but its aridity makes the habitability marginal; if there were intelligences on Mars, they would do something about this; the obvious thing to do would be to build a network of long straight canals. And since this is what we see when we look at Mars, this is what must have happened.
With this leap of the imagination, Lowell created one of the most enduring tropes of science fiction: Mars as a dying planet. It would live on in the works of H. G. Wells, Edgar Rice Burroughs, Leigh Brackett and many, many others. And if his interpretation of what he saw did not win as much favour among his astronomical colleagues as it did in the popular imagination, it was not because the idea of life on Mars seemed too far-fetched. Observations of the way the planet’s brightness and colour seemed to change with the seasons made plant life there seem almost certain; if plants, why not animals and why not intelligence? The most weighty argument against Lowell’s Martians was simply that over time other, better observers consistently failed to see the canals as continuous and linear, if they saw them at all. The lack of evidence of engineering, not the implausibility of life on Mars, was what counted against Lowell – a belief in life on Mars was quite commonplace.
Today this easy acceptance seems rather remarkable. At the beginning of the twenty-first century, when the possibility of life elsewhere has become the central preoccupation of space exploration, its discovery is routinely held up as the most important discovery that could ever be made. What accounts for this change?
A large part of the answer lies in the nature of astronomy. Copernicus’s proposal that the earth was not the centre of the solar system changed the way that astronomers looked at the sky. If the earth was no longer the fixed centre, then it was a wandering star like the five which shuffled back and forth across the zodiac: a planet. Previously unique, now it was one member of a class and must have similarities to its classmates. The world had become a planet and so the planets must become worlds, a process accelerated by the Galilean discovery that, like the earth, the planets were round and had features. In this context it was quite normal to believe that one of the things that the planets had in common was life, especially since, after Copernicus, many astronomers tended to go out of their way to deny the earth any special attributes. As Lowell put it in Mars (1896), ‘That we are the only part of the cosmos possessing what we are pleased to call mind is so earth-centred a supposition, that it recalls the other earth-centred view once so devoutly held, that our little globe was the point about which the whole company of heaven was good enough to turn. Indeed, there was much more reason to think that then, than to think this now, for there was at least the appearance of turning, whereas there is no indication that we are sole denizens of all we survey, and every inference we are not.’ A Copernican stance could easily lead astronomers to the assumption of life, not lifelessness, as the status quo.
Another part of the answer is that in Lowell’s day a belief in life on Mars was largely without consequences. As Alfred Lord Tennyson noted as early as 1886, our astronomical observations of planets and our dreams of what might transpire on them were separated by a vast gulf:
Hesper – Venus – were we native
to that splendour or in Mars,
We should see the Globe we groan in,
fairest of their evening stars.
Could we dream of wars and carnage,
craft and madness, lust and spite,
Roaring London, raving Paris,
In that point of peaceful light?
Life on Mars might be likely, it might be inevitable, it might even be intelligent, but the possibility of people ever actually visiting Mars – or Martians visiting earth – was more or less pure fancy. This made Martians fascinating but not important, rather in the way of dinosaurs – another turn-of-the-century craze. Whatever evidence scientists might find of dinosaurs, or speculations they might produce about them, without a time machine encounters with dinosaurs were impossible. Similarly, without a space machine, encounters with Martians were impossible.
So while there might be intelligent Martians, there could be no links of history or interest between them and us. This gave the Martians an interesting rhetorical niche that they quickly made their own: ‘The man from Mars’ became the quintessential intelligent outsider, unswayed by any relevant prior worldliness, unattached to custom. He retains that position to this very day; his natural habitat is the newspaper op-ed page and other didactic or satirical environments, but he turns up elsewhere, too. Temple Grandin, the highly articulate woman with autism in Oliver Sacks’s An Anthropologist on Mars, applies the titular image to herself as a way of stressing her disassociation from the ways of the world around her; the wonderfully innocent yet artfully contrived metaphors of the poems in Craig Raine’s A Martian Sends a Postcard Home led to a whole school of poetry (if a small one) being dubbed ‘Martianism’. One of the most influential science fiction novels of the twentieth century, Robert Heinlein’s Stranger in a Strange Land, achieves its impact by showing us the earth through the eyes of a true ‘man from Mars’ – a human brought up on Mars by Martians.
Rhetorical devices aside, believing in Martians made little difference to the earthly lives of Lowell’s readers and this, I suspect, is one of the things that made them easy to believe in. Another spur to belief was the difference that the existence of Martian minds made to the way earthly imaginations saw Mars. One of the Copernican ways in which Martians made the planet Mars a world like the earth was that they made it a place experienced from the inside, a site for subjectivity. Without minds, Lowell argued, Mars and the other planets were ‘mere masses of matter’ – places without purpose, frightening voids. With minds, they were worlds.
To Lowell, there was no really useful or involving way to think about a planet except as a world inhabited and experienced by mind. The space age, though, has brought us new ways of seeing beyond the earth and changed our way of thinking about what we see. Our spacecraft, tools of observation but hardly observers in themselves, have shown us things we know cannot be witnessed directly or experienced subjectively, but which can still fascinate. The post-Copernican elision between worlds (structures of shared experience and history) and planets (vast lumps of rock and metal and gas that orbit a fire yet vaster) has been rewritten. Yes, the earth that is our world is also a planet. But not all planets are worlds. We no longer need the point of view of a mythical Martian to imagine Mars, or to convince us that Mars might be worth imagining. Now that our spacecraft have been there we can know it intimately from the outside, know it as an objective body rather than a subjective experience. We can measure and map its elemental composition and its wind patterns and its topography and its atmospheric chemistry and its surface mineralogy. The planet Mars can fascinate us just for what it is.
If the space age has opened new ways of seeing mere matter, though, it has also fostered a strange return to something reminiscent of the pre-Copernican universe. The life that Lowell and his like expected elsewhere has not appeared, and so the earth has become unique again. The now-iconic image of a blue-white planet floating in space, or hanging over the deadly deserts of the moon, reinforces the earth’s isolation and specialness. And it is this exceptionalism that drives the current scientific thirst for finding life elsewhere, for finding a cosmic mainstream of animation, even civilisation, in which the earth can take its place. It is both wonderful and unsettling to live on a planet that is unique.
Yet if the earth is a single isolated planet, the human world is less constrained. The breakdown of the equation between planets and worlds works both ways. If there can now be planets which are not worlds, then there can be worlds that spread beyond planets – and ours is doing so. Our spacecraft and our imaginations are expanding our world. This projection of our world beyond the earth is for the most part a very tenuous sort of affair. It is mostly a matter of imagery and fantasy. Mars, though, might make it real – which is why Mars matters.
Mars is not an independent world, held together by the memories and meanings of its own inhabitants. But nor is it no world at all. More than any other planet we have