“How is your qube?” Wahram asked after a while.
“She’s all right,” Swan said dismissively. “She says my head served as good insulation for her.”
“Oh dear.”
They followed the sunwalkers down the hall, took stairs down to a set of large rooms below.
The biggest room down there contained a scattering of couches and low tables, and the long bar of a communal kitchen. Swan introduced herself and Wahram to the three sunwalkers, who were people of indeterminate age and gender. They nodded politely at Swan’s introduction, but did not identify themselves. “How is your arm?” Swan asked the hurt one.
“It’s broken,” the person said simply, and held it out a little. “Clean hit, but the rock was small and just falling, I guess. Tossed up in the big hit.”
Now it seemed to Wahram that this one at least was young.
“We’ll wrap it,” one of the others said, also young. “We can try to straighten it, and then wrap it with a support, no matter how straight it is.”
“Did any of you see the meteor strike?” Swan asked.
They all three shook their heads. All young, Wahram thought. These were the kinds of people who walked around Mercury right before sunrise, torching themselves with solar visions. Although apparently Swan was also one of them. The young in spirit, then.
“What are we going to do?” he asked.
“We can take the utilidor west till we get to the next spaceport on the nightside,” one of them said.
“Do you think the utilidor is still passable under the hit?” Swan asked.
“Oh,” the one said. “I didn’t think of that.”
“It might be,” said the one with the broken forearm. The third one was looking in cabinets against the wall. “You never know.”
“I doubt it,” Swan said. “But I guess we can go look. It’s only about fifteen klicks away.”
Only fifteen! Wahram didn’t say. They stood there looking at each other.
“Well, shit,” Swan said. “Let’s go take a look. I don’t want to just sit here.”
Wahram suppressed a sigh. It was not as if they had a great number of choices. And if they could get through to the west, and hurried, they could catch up to the night, and hopefully the spaceport where the people from Terminator had gone.
So they went to a door at the west end of the room and went through it into a passageway, lit dimly by a string of overhead lights that were part of the ceiling. The walls of the tunnel were raw faces of rock, in some places cracked, in others bare walls with drill bit marks angling upward on their left and downward on their right. They hiked west at a good clip. The one with the broken arm seemed to be the fastest of them all, although one of the other sunwalkers stuck close by the hurt one. No one spoke. An hour passed; then, after a short rest sitting on some cubical blocks of rock in the tunnel, another hour. “Did your Pauline get an image of the strike?” Wahram asked Swan when they were walking again. The utilidor was wide enough for three or four people to walk abreast, as the sunwalkers were proving ahead of them.
“I’ve looked, but it’s just a flash to one side. Only a few milliseconds of light before the explosion upward and out, coming down fast and hot. But why hot? There’s no atmosphere to heat it, so that doesn’t make sense. It kind of looks like it came from, I don’t know, somewhere else. From some other universe.”
“Seems like some other explanation will be forthcoming,” Wahram could not help saying.
“Well, you explain it,” she said sharply, as if speaking to her qube.
“I can’t,” Wahram said calmly.
They walked on in silence. Presumably at some point they were walking underneath the city. Above them, Terminator would be burning up in the day’s rain of light.
Then the tunnel ahead of them appeared to end. They had all put their helmets back on, as it was the easiest way to carry them, and now they shone their helmets’ headlamps into the darkness before them. A mass of rock rubble filled the tunnel, floor to roof. It was cold here, and suddenly Swan said, “We’d better seal our helmets,” and her faceplate slid down. Wahram did the same.
They stood there looking at the blockage.
“All right,” Swan said grimly. “Can’t go west. We’ll have to go east, I guess.”
“But how long will that take?” Wahram said.
She shrugged. “If we sit here, it will be eighty-eight days till sunset. If we walk, it will be less.”
“Walk around half of Mercury?”
“Less than half, because we will be walking and the planet will be rolling. That’s the point. I mean, what else are we going to do? I’m not going to sit here for three months!” She was almost in tears, he saw.
“How far is it again?” he asked, thinking half of Titan as he said it. His stomach contracted within him.
“About two thousand kilometers. But if we walk east at, say, thirty kilometers a day, we shorten the wait time to something more like forty days. So we can cut it in half. That seems worth it to me. And it doesn’t have to be continuous walking. I mean, it’s not like the sunwalkers. We walk a day’s worth, eat, sleep a night, then walk again. Set a daily schedule. If we hiked for twelve hours out of every twenty-four, that would be a lot, but it would save even more days. What, Pauline?”
“Can you turn up Pauline’s voice again?” Wahram requested.
“I don’t want to now. She says twelve-hour days of walking would shorter our time down here by around forty-five days. That’s enough for me.”
“Well,” Wahram said. “That’s a lot of walking.”
“I know, but what are you going to do? Sit here for over twice as long?”
“No,” he said slowly. “I guess not.”
Although really it would not be so very long. A rereading of Proust and O’Brian, a few times through the Ring cycle; his little wristpad was very well stocked. But the way she stood there looking at him, these were not thoughts he felt comfortable expressing.
“I’ll turn up Pauline,” she said, as if giving him something in exchange for his agreement.
“ Solvitur ambulando,” Pauline said. “Latin for ‘It is solved by walking.’ Diogenes of Sinope.”
“Thus you prove motion is real,” Wahram supposed.
“Yes.”
Wahram sighed. “I was already convinced.”
B ack at the first underground station they took stock. The three sunwalkers were perfectly happy to walk for six or seven weeks; it was very like their usual mode of existence. Their names were Tron, Tor, and Nar. They were gender nondescripts as far as Wahram was concerned, and seemed to him very young and simple. They lived only to hike around Mercury; they seemed to know nothing more than that, or perhaps they didn’t speak much to strangers. But what they did say seemed childlike to him, or provincial in the extreme. There were whole terraria filled with such folk, of course, but he had gotten used to thinking of the Mercurials as highly sophisticated, steeped in history and art and culture. Now he was learning that it was not universally true. He realized he had thought sun worshippers would be followers of the various early solar religions of ancient Egypt, Persia, the Inca-but no. They just liked the sun.
It looked like they were going to have to spend a couple of nights sleeping on the floor of the unimproved tunnel in between each way station. “Every third day,” Swan said, “we can resupply. It sets a good goal.”
“We might even be able to go farther,” Tron said shyly.
Tron was the one with the broken arm, so Wahram refrained from mentioning that for him personally, thirty- three kilometers a day might prove enough, or too much. That he might be the drag on this group was discouraging. In any case Swan was overseeing the filling of backpacks she had found in the emergency supply cabinets: their spacesuit helmets, some emergency air, water bottles, food, air mattresses, a little pot and stove. A roll of aerogel blankets, not very warm-looking, but the utilidor would stay at this temperature, Swan said; and it was pretty warm.
So: tunnel walk. Possibly similar to spelunking expeditions of long duration. Little headlamps were included in the packs too, although for now they were not necessary, as the ceiling held a warm square of yellow-white light every twenty meters or so, illuminating the rough rock of the utilidor very well. They were about fifteen meters underground, Swan said. The tunnel had been drilled through bedrock or regolith, with a heat finish that had imparted frequent swirls and dashes of mineral color, reminiscent of the cut surfaces of certain meteorites. In some
