“Thank you, Captains,” Samuel datavised. “We’ll try to be as quick as we can.”

“If things get too hot, let us know,” Joshua replied.

“We’d better get on,” Samuel told the team. “Every minute of lead time could be indispensable later.” He ordered his backpack to fire the cold gas jets, and slid easily along the corridor to the first big airlock. Monica triggered her own backpack, and glided after him.

The corridor flared out around the airlock, which was a typical example of Tyrathca engineering: a square of titanium four metres in diameter with rounded corners, edged with locking seals, thick, sturdy, and reliable. And vacuum welded into place. The archaeology team had solved the egress problem by cutting out a metre-wide circle of metal from the Tyrathca slab and installing their own airlock. It was a simple mechanical hatch with frictionless hinges and seals. A chrome handle was half-recessed in the middle, with standard operating instructions stencilled beside it.

Samuel secured himself and pulled the handle. His armour’s power augmentation barely kicked in to help. The handle slid up, and rotated ninety degrees.

“One up to human engineering,” Renato datavised as Samuel pushed the hatch inwards.

“Not really,” Oski datavised. “It’s our materials science that makes the difference. The hatch was designed for longterm vacuum exposure. Their airlock was built with regular maintenance services in mind.”

There was another corridor identical to the first on the far side of the airlock. One of the serjeants shut the small hatch after them. This corridor also ended in a big titanium airlock, with an identical human hatch inserted. Samuel pulled the lever up. Before he could attempt to push the hatch open, his suit sensors advised him of an environment change. “It’s venting,” he datavised. “Very small nitrogen release, minute contamination. Pressure must be equalising.”

“Open it,” Monica datavised. “There can’t be any real atmosphere in there. We’re wasting time.”

Samuel gripped one of the titanium spars with one gauntlet, and pushed with the other. The suit’s power augmentation whined on the threshold of audibility. A whirl of silvery dust scooted around Samuel’s armour as the hatch flipped back.

“Just how many of these corridors are there?” Renato asked as he air-swam through, only to be faced with yet another blank rock shaft. His inertial guidance display showed him it was inclined slightly, heading away from the rotation axis. Though there was still no appreciable gravity.

“This is the last one, according to our file,” Samuel said.

The airlock at the far end had a human hatch in it; there was also a small plaque.

HIGH YORK UNIVERSITY

ARCHAEOLOGY EXPEDITION OF 2487

We respectfully offer our tribute to the generations of Tyrathca who ventured forth in this vessel.

In this place we have stumbled through the remnants of greatness, eternally thankful for the glimpse of nobility they reveal.

Though the Tyrathca have no god, they are clearly not devoid of miracles.

Renato floated over to the silvered plaque after Monica moved aside. “Well that’s a nice way to start,” he datavised. “The archaeology expedition never found any reference to a Tyrathca god.”

“We knew that already,” Oski datavised. “Besides, I doubt they were looking. The only memory files they accessed were in the systems management architecture. We’ve got to go a lot deeper than that to find anything useful.”

Samuel shifted his sensors from the plaque to the hatch. “I don’t think I’ve ever felt more like a grave robber.”

“There have been worse assignments,” Monica datavised. “For you as well as me, I suspect.”

Samuel didn’t reply. He grasped the hatch’s handle and pulled up. This time there was a significant gas vent.

“This is it,” Oski datavised. “We’re in. Terracompatible nitrogen oxygen mix, several trace gases. Three per cent standard atmospheric pressure. No water vapour content. Guess it’s too cold. Registering thirty degrees below zero.”

“Checks with the file,” Monica confirmed. Samuel pushed the hatch open and glided through.

The archaeology expedition had spent six weeks exploring the interior of Tanjuntic-RI. Given the timescale, it could hardly be thorough. But the main sections were all mapped, allowing the nature of the arkship’s engines and environmental maintenance mechanisms to be inspected. Tanjuntic-RI was arranged in three principal levels. Along the rotation axis were three long cylindrical chambers six hundred metres wide. Each contained a shallow lake which served as the principal biological recycling system. The water was a combination fish-tank/ algal air regenerator, powered by a thermal lighting array strung along the axis. Surrounding that was an extensive warren of hemispherical caverns linked by kilometre after kilometre of broad corridors. This level was devoted to engineering and flight maintenance; the caverns filled with machinery, everything from fusion generators to chemical filtration plants, cybernetic factories to mineral storage silos. The rear quarter of the caverns were all used to house support systems and fuel for the fusion engines.

Encircling the second level were the eight principal life support rings. Tunnelled out of the rock and lined with metal, like giant binding bands; they had a rectangular cross section, five hundred metres wide, a hundred metres high. Their floor was a single looped strip of Tyrathca tower houses threaded by narrow roads of greenery, a computer design program’s notion of urban pleasantries.

“We need the third level, ring five,” Oski datavised as soon as they were through the last airlock. “That’s where the archaeologists found the control offices.” A three dimensional map of the interior expanded into her mind. Her guidance block extended a glowing green line through the tunnels, linking her present location to ring five.

The last airlock had brought the team into a standard-sized corridor that circled the forward end of the arkship. Over a hundred other corridors branched off from it. Gravity was barely noticeable, taking several minutes to pull objects towards the floor. Monica used her gas jets to take her over to a clump of human crates stacked against the wall. The thin, freezing atmosphere had turned the white plastic a faint cream. She read some of their labels. “Nothing we can use,” she datavised. “It’s their camp equipment. Programmable silicon shelters, life support units, microfusion generators; that kind of thing.”

“What about lighting?” a serjeant asked.

“Good question.” Monica shifted position, scanning more labels. “Yes, here we go. Monochrome projectors, three hundred metre illumination radius. I don’t think they’re self powered, though.”

“Leave it,” Samuel datavised. “We don’t have the time.” He fired his manoeuvring pack and started drifting along the corridor. The wall opposite the airlocks had archways leading away into the interior, their depth defeating his suit sensors and lights. “There should be a lift here somewhere. Ah.” The fifth archway had a palm-sized plastic disk stuck on the wall beside it, a small lifelong beacon light in the centre. Samuel couldn’t resist flicking it with a gauntlet finger as he went past. There was no spark of light from the beacon, its tritium-decay power source had been exhausted decades ago.

His gas jets squirted strongly, steering him through the archway. Fifteen metres down the corridor was a lift door: a single panel of metal ten metres long and three high. The team didn’t even pause by it. There was a smaller door on either side, each heading a ramp that spiralled, DNA-fashion, around the entire length of the lift shaft. One of them was open; it had a dead light beacon just inside.