"How thick do you suppose the ice is here?" asked James as they pulled on their surface suits in the outfitting room.
"Still plenty thick enough to support the weight of the rovers," said Andrew. "Don't worry, we're not going to fall through."
"I wasn't worried about that," his son replied as he pulled the tight fitting material up his thighs and around his waist. "They say there are probably still living creatures down there, on the sea floor. The deep oceans will never freeze, they say. Not for billions of years, anyway. The ice acts as insulation, keeps the Earth's inner heat in."
"Yeah," agreed Andrew. "I heard that."
"One of my science teachers said that life might actually last longer down there than if the Earth hadn't been thrown out of orbit," James added as he pulled the suit's arms on. "Because the sun's continually growing brighter and the Earth's surface temperature would have exceeded the boiling point of water within just one billion years. The planet would have been completely sterilised."
"Life, uh, finds a way," said Andrew, making James laugh. "Did you know," Andrew added, "that the underground cities were almost underwater cities? They thought for a while about building the cities at the bottom of the oceans. We'd have been able to come and go the entire two hundred years The Freeze was going on, not trapped in the cities. We'd have been surrounded by a living ecosystem."
"So why didn't they do it that way?"
"It was probably easier to get the construction equipment to sites on the surface. I don't know, there were probably loads of technical reasons." He picked up his helmet and studied the status readouts on the back, the readouts provided for a second person to read. He didn't want to put it on his head while they were still talking. The intercom wasn't the same, and he enjoyed talking to his children.
"It would have made it a lot harder for the mobs to attack the cities," James pointed out. "A lot of the cities that fell might still exist."
"I don't think they expected the attacks to be so furious," Andrew replied. The display said his suit was in good condition. Ready for a stroll on the surface. "They trusted the defenders and the automatic weaponry. Your suit ready?"
"Yep." James put his helmet on and Andrew did the same. The teenager's voice came to Andrew by way of the speakers by his ears, thin and tinny compared to hearing him directly. "So, let's see what these things feel like."
Hanging on the wall were two garments they'd never had to wear before. They had been designed by engineers back in the city just in case anyone ever had to try crossing the Atlantic, and had then been left in storage for twenty years because everyone had been too sensible to try such a mad idea. They looked like the arms, torso and helmet of a medieval suit of armour but were made of a polymer, ceramic composite that was both light and resistant to becoming brittle at low temperatures. Additional pieces of armour fitted around their legs and feet. The father and son helped each other into them and did up the clip fastenings before standing back to admire each other.
"Feels really easy to move," said James, lifting an arm experimentally. "Not as heavy as I thought they'd be."
"Let's go try them out properly," said Andrew. "Shall we go?" He indicated the airlock. James nodded and they went in together.
The inner door closed behind them and the outer door opened, letting the air escape to become a shower of crystals falling to the ground. The ladder deployed and Andrew led the way down onto the ice.
A few hundred kilometres further to the west lay the Mid Atlantic Cryovolcanic Ridge. Europe and the Americas were slowly drifting apart as continental drift continued, the Earth's mantle and crust not caring in the slightest that the planet had been cast adrift from the solar system. As the Atlantic widened, cracks opened up, not only in the sea bed, letting magma well up to form a chain of conventional lava volcanoes on the ocean floor, but also in the thick layer of ice that covered the still liquid deep ocean. Water, pushed up by the weight of the ice above it, gushed up through the gap to form cryovolcanoes. Like ordinary volcanoes but with water instead of lava and ice instead of rock. Usually the water just flowed, boiling in the vacuum and freezing as it lost its heat to the empty sky above, but occasionally forces in the deep ice caused pressure to build up in the water until something gave, and then water would be erupted into the sky with great force, sometimes carried hundreds of kilometres upwards before falling again as shards of ice.
Somewhere to the west, such an eruption was happening now and there was snow falling around the halted caravan of hab-rovers. Not the light, fluffy snow from the old movies that drifted lazily and was carried sideways by the wind but hard needles of ice that fell with the speed and force of bullets in the vacuum, shattering where they hit the ground. Andrew and James felt it hammering on their heads and shoulders, trying to beat them to their knees. They forced themselves to remain standing, to remain under the overlapping sheets of armour, knowing that if they fell any shard of ice that found a gap would go through their surface suits and the delicate flesh beneath like a knife, not only cutting but also freezing them, maybe turning an entire limb as hard as marble. The only remedy then would be amputation.
The surface consisted of gravelly water ice that glittered in the light of the distant sun so that it looked as if they were walking on diamonds. It danced as it was hammered by the continuing barrage and the impacts threw a constant haze of fine particles above the ground creating an almost ethereal spectacle, as if they'd somehow found their way to a strange, magical land of miracles. Above them, the sun was ringed by a halo where its light was scattered by the still falling ice crystals.
"It's beautiful!" said James in awe. "Beautiful and deadly."
"Maybe you'd better go back in," said Andrew anxiously as the barrage on his body reached a new intensity. "I didn't realise it was this bad. I'm pretty sure we can manage this without you."
"Joe's only three years older than me and he's outside," James replied, pointing at two shadowy figures visible beside the next rover ahead. "I'll be okay." Without waiting for his father to reply, James began walking towards Joe and Philip, his head bowed as if he was trying to keep rain from running down his collar. Cursing under his breath, Andrew ran to keep up with him.
Philip and Joe were busy removing one of the bridge segments strapped to the side of their rover. Each rover carried two segments, one on either side. James, joining them, began to undo one of the clasps holding the rear of the segment firmly in place and Andrew went to work on another. With Philip and Joe at the other end of the segment they soon had it loose and a system of helium hydraulics lowered it gently to the ground while the ice continued to fall, shards flying in all directions as they ricocheted off the latticed steel beams. Philip went to a control panel at one end of the segment, touched a couple of the controls and it unfolded lengthwise to three times its original width bringing large, steel wheels into contact with the ground.
Li, his wife, Lungelo and his daughter, meanwhile, had unloaded the bridge segment from the other side of Philip's rover, unfolded it and were driving it forward, toward the wide crevasse that had halted the caravan. "These things were designed to anchor in solid ice," said Valentina. "How will they hold up in this loose gravelly stuff?"
"Maybe it's not too thick," suggested Joe. "Just a few centimetres maybe."
Andrew went as close to the edge of the crevasse as he dared. "Susan," he said. "Shine the spotlight over here, will you?"
Through their rover's cockpit window, lit up brightly in the twilight that passed for noon on the runaway planet, Andrew saw her raise a hand in reply and a moment later the beam of the searchlight was lighting up the opposite side of the crevasse. "The loose stuff looks to be about fifty centimetres deep," he said. "We'll have to blast it. Someone get some charges."
Joe went back inside to get them. When he returned with a box of the small explosive devices he walked confidently to a position in which to start laying them but Andrew stopped him, taking the box from him. "Philip, you're the heaviest," he said. "I want to tether myself to you. If the gravel gives way, falls into the crevasse, I don't want to go with it."
"I'll keep you safe," Philip promised as Andrew attached his belt tether to his waist. Andrew then returned to the edge while Philip tethered himself to Lungelo and Lungelo tethered himself to Philip's rover. Then, seeing they were ready, Andrew opened the box and began laying out the charges, digging out a small depression for each one and turning a tab in the top to arm it. He was laying the third charge when the loose gravel under him began to shift. Andrew dropped into a crouch as the ground under his feet moved towards the crevasse, ice falling over the edge in a silvery shower. Philip braced himself as the tether between them pulled taut, allowing Andrew to climb forward, off the unstable area.
"Be careful!" gasped Susan from the cockpit.
"No worries," said Andrew, trying to remain calm. "Shit, we lost two of the charges over the edge. I'll lay some more."
There were some more minor ice falls as he continued laying them out, and all the while the ice storm continued, some of the falling ice crystals hitting the charges he was laying with enough force to dent the metal casing. He wondered if there was any chance they might be set off accidentally. They were pretty sturdy, but even so... He finished as fast as he could and then almost ran back to the others, all of them taking shelter behind Philip's rover. They all looked in the box, checking for themselves that the remaining charges weren't armed, and then Andrew picked up the detonator. "Ready?" he asked. They all nodded. "Okay. Three, two, one..."
He pressed the button and the ground by the edge of the crevasse erupted in a silvery shower. The ground jumped under their feet as the shock wave reached them. All along the crevasse, ice poured down into the darkness from both sides and they waited patiently for things to settle down before emerging from their shelter.
Andrew, again at the end of the chain of tethered people, returned to the spot to find that an area of nearly fifty square metres had been cleared of loose ice, but it revealed a new problem. "The nitrogen ice is fractured in several places," he said. "We're going to have to start further back. We're going to need a third bridge segment."
"Roger," said Philip. "Me and Joe'll get one of yours."
Andrew laid some more charges to extend the cleared area further from the crevasse. Li and Lungelo, meanwhile, were supervising the joining of the first two bridge segments, and when Philip and Joe drove the third segment over they watched as it attached itself as well. Green lights lit up to show that the connections were secure, and then one light shattered as it was hit by a falling shard of ice.
"I will be really annoyed if we find that this crevasse is only a few klicks long," said Izindaba "and that we could have just driven around it."
Andrew felt the same way. Wide though it was, the crevasse was too narrow to show up on the terrain maps the satellites had provided. They'd already had to navigate a maze of crevasses so wide that they could have been described as canyons. He really didn't want to lose any more time. Not when they were on such an important deadline.
Andrew and Philip drove the completed bridge towards the crevasse until its forward-most point was on the last piece of unbroken ice. Andrew then deployed the anchoring poles. The poles, formerly stowed horizontally against the side of the bridge, turned slowly until they were standing vertically and heating elements began to warm them, causing the nitrogen ice below to sublime to vapour. The poles slowly began to descend into the holes created.
It took half an hour, but finally the poles had sunk to their full depth and the bridge diagnostics declared that they were solid and secure. "Good," said Andrew. "I think we're ready to extend."
"Do it then," said Lungelo," so we can get back inside. I'm freezing!"
They were all cold. It was evident in the way they were shuffling around, trying to generate heat. Shards of ice from the downpour were becoming lodged in gaps in their armour, stealing heat from the surface suit below which, except for the boots and gauntlets, weren't designed to withstand direct contacted with the cold. They were all likely to have frostbitten spots here and there on their bodies when they were finished. "Everyone else go back inside," he said therefore. "I can finish here."
"You might need help," James protested.
"I'm fine," Andrew lied. There was a spot by his left shoulder that had gone numb. He tried not to let it worry him. "All I've got to do is push a few buttons. I'll be okay."
The others reluctantly made their way back to their rovers, crouched over as the onslaught reached a new intensity. Andrew had been told that ice storms like this were rare, but when they happened they could last for days, even weeks. Just their luck to have come upon one now.
He pushed a button and the bridge began extending itself across the crevasse. The end reached the edge and reached out across it, the frontmost pair of wheels dangling over the drop. Andrew watched the anchor poles anxiously, dreading to see them pull loose as the weight of the bridge pulled the far end down.
The poles held, though, and the far end of the bridge reached the other side of the crevasse, the wheels lifting up onto the gravelly surface. Andrew stopped it before they'd gone more than a couple of metres further, though, and walked across, carrying the box of explosive charges with him. The bridge consisted mainly of steel bars with a thin grill laid across them. It gave him a clear view of the drop beneath him that he tried hard not to look at.
Arriving at the other end, he used the explosives to clear another patch of clear ice. Then he finished extending the bridge and deployed the anchor poles. The Bridge performed another self diagnostic and declared itself ready to take traffic. "Good," said Andrew. "I'm coming back. Pretty sure I've got ice in my armour."
Susan gasped with shock. "Get back here right now!" she commanded. "Right now."
"On my way." He began walking back across the bridge.
"Why didn't you say something sooner?"
"I wasn't finished."
"Anyone could have pushed a few buttons. It's not worth crippling yourself for."
"She's right, Andy," said Philip. "You'd soon tell us off if we did something like that. We're a long way from medical help out here."
"I'm sure it's just a few blisters. I've had worse. Be sending the cargo rover over. See if the bridge holds."
Philip acknowledged the order, and as soon as Andrew was safely off the bridge he started up the unmanned vehicle and began driving it forward.