And each day, when it stands over your horizon at all, it’s closer. It tends to stay over the horizon longer; but never all the time, as very often you drop into the depths of the next sink in this sunken land. But eventually, continuing roughly eastward, every time you are not actually in the depths of a pothole, the cliff positively looms over the world to the east, towering over the horizon, which stubbornly remains no more than five kilometres away. So at that point you have two horizons, in effect; one near and low, the other far and high.
And eventually you get so close to it that the cliff simply fills the eastern sky. It rises astonishingly near the zenith; it’s like running into the side of a bigger world. Like crawling over a dry cracked sea bed to the side of a continental shelf. The gullies and embayments in the cliff are whole landscapes in themselves now, canyon worlds of great depth and even greater steepness. Every spur between them is now seen to be a huge buttress, ribbing the side of a higher world. The occasional horizontal ledges marking the buttresses appear big enough to support complete island estates. But it’s hard to tell from below.
And indeed, by the time you reach the point called Cliff Bottom View, where you stand on one of the last high points of the chaos, nearly as high as the narrow strip of hilly plateau between the chaos and the escarpment, and you can finally see all the land between where you are and the foot of the great cliff, you can no longer see the cliff’s top. The mass of it blocks your view, and what you see rimming the sky, so far up toward the zenith, is not the true top, though it can seem so if you have not been paying attention, but is rather some prominence part way down its side.
Only by getting into a small blimp and taking off into the air, and flying up and away from the cliff, backing out over the eastern part of the chaos, can you see the whole extent of it. If you keep sight of a reference mark, you can see that what down in the last camp you took for the top of the cliff was only about two-thirds of the way up it; the rest was blocked from view; and in any case the very strong optical effect of foreshortening had deceived you as to the true height of the thing. You keep floating up into the air, up and up and up, like a bird gyring on an updraught, and finally seeing all the cliff at once from this perspective we just started to laugh, we couldn’t help it – we were laughing or crying, or both at once, our mouths were hanging open to our chests, we positively goggled at it, and there was nothing really we could say, it was so big.
There are places out in Argyre that are nothing but flat sand to the horizon in every direction.
Usually the sand is blown into dunes. Any kind of dune, from very fine ripples underfoot to truly gargantuan barchan dunes. But in some areas even that is missing, and it is simply a flat plane of sand or bedrock, with the sky arching over it.
They say that if you look at it closely, the sky forms the visual equivalent of a dome overhead. Not a true hemisphere, but flattened somewhat. This is a virtually universal human perception, the result of consistent over-estimation of horizontal distance compared to vertical distance. On Earth the horizon seems to be two to four times farther off than the zenith overhead, and if you ask someone to divide the arc between the zenith and the horizon evenly, the point chosen averages well less than forty-five degrees; about twenty-two degrees by day, I have found, and thirty by night. Redness increases this effect. If you look at the sky through red glass it appears flatter; if through blue glass, taller.
On Mars the unobstructed horizon is only about half as far away as it is on Earth – about five kilometres – and sometimes this simply makes the zenith seem even lower – perhaps two kilometres high. It depends on the clarity of the air, which of course varies a great deal: sometimes I have seen the dome of the sky appear ten kilometres high, or even transparent to infinity. Mostly lower than that. In fact the vault of the sky is a different shape every day, if you will take the time to look at it carefully.
But no matter the transparency of the sky, or the shape of the dome it makes overhead: the sand is always the same. Flat; reddish brown; redder out toward the horizon. The characteristic redness occurs if even one per cent of the bedrock or the dust on the ground is made up of iron oxides such as magnetite. This condition obtains everywhere on Mars, except for the lava plains of Syrtis, which when blown free of dust are nearly black – one of my favourite places (also the first feature to be seen from Earth through a telescope, by Christiaan Huygens in 1654).
In any case: a perfect red plane in all directions, to the round horizon. Inside certain flat craters, you stand at the centre and see a double horizon, in fact: the lower one five kilometres away, and perfectly straight; the higher one farther away, and usually less straight, even serrated. (This second horizon also considerably flattens the dome of the sky.)
But the completely flat areas are the purest view. Much of Vastitas Borealis is so flat that only millions of years of existence as the floor of an ocean can explain it. And parts of Argyre Planitia are equally flat. We cannot lose these places. In these regions one stands confronted by a radically simplified landscape. It is a surreal experience to look around oneself – surreal in the literal sense of the word, in that one seems to stand in a place ‘over-real’, or ‘more than real’ – a higher state than reality; or reality revealed in its barest, most heraldic simplicity. The world says then, This is what the cosmos consists of: rock, sky, sun, life (that’s you). What a massive aesthetic impact is conveyed by this so-simplified landscape! It forces you to pay attention to it; it is so remarkable you keep looking at it, you cannot do or think anything else – as if living in a perpetual total eclipse, or within any other physical miracle. Which of course is always the case. Remember.
1. FINDING HIM
After she saw the strange face through the bottle in the farm of the Ares, Maya couldn’t stop thinking of it. It frightened her, but she was no coward. And that had been a stranger, not one of the hundred. There on her ship.
And then she told John about it, and he believed her. He believed in her; and so she was going to have to track that stranger down.
She began by calling up the plans for the ship and studying them as she had never studied them before. It surprised her to find how many spaces it contained, how large their total volume. She had known the areas the way one knows a hotel or a ship or a plane, or one’s home town for that matter – as a set of her life-routes, wound through the whole in an internal mental map, which itself could be called up sharply visible in her mind’s eye; but the rest was only vagueness, deduced, if she ever thought about it, from the parts she knew; but deduced wrongly, as she now found out.
Still, there was only so much liveable space in the thing. The axis cylinders were not liveable, by and large, and the eight toruses were, for the most part; but they were also very heavily travelled. Hiding would not be easy.
She had seen him in the farm. It seemed possible, even perhaps likely, that the man had allies in the farm crew, helping him to hide. A lone stowaway, unknown to anyone aboard, was difficult for her to believe in.
So she began in the farm.
Each torus was octagonal, made of eight American shuttle fuel canisters that had been boosted into orbit and then coupled together. More bundled canisters formed the long axis that speared down the centres of the torus octagons, and the octagons were connected to the central axis by narrow spokelike passage tubes. The entire spacecraft spun on the long axis as it moved forward toward Mars, spinning at a speed which created a centrifugal force the equivalent of Martian gravity, at least for people walking on the floors set against the outside of the torus rings. The Coriolis force meant that if you walked against the rotation