Pandora's Star

by Peter F. Hamilton

  ‘One million kilometres, sir,’ Sandy Lanier reported.

  ‘Take us out of hyperspace.’

  One of the portals switched to an image of pure aquamarine blue. Dark streaks blossomed from the centre, and peeled open. This time they didn’t have to switch the sensors to infrared to see the barrier.

  ‘My God,’ Tunde said hoarsely. ‘It’s becoming transparent.’

  Dyson Alpha was wavering in and out of visibility thirty AUs ahead of them, only marginally brighter than the rest of the stars behind. The fluctuations indicated by the hysradar scan were inaccurate, the barrier wasn’t moving in any physical dimension, it was losing cohesion.

  ‘Sensors, defence, is there anything shooting at it?’ Wilson asked desperately.

  ‘No, sir. No energy of any kind. Local quantum state is also stable as far as we can tell. The barrier is . . . Oh wow! It’s gone! Hysradar scans are clear. The fucker’s vanished.’

  Wilson stared at the two portals. The one with the gravitonic scan was empty. A second later, when the light reached them, Dyson Alpha burned steadily at the centre of a colossal blank circle.

  We’re still seeing the other side of the barrier, he realized, it’s going to take the light from the stars beyond over four hours to travel thirty AUs.

  ‘Full passive sensor sweep,’ Wilson ordered. ‘Show me what’s in there.’

  ‘This can’t be coincidence,’ Oscar said. He sounded shocked, even a little frightened. ‘It’s been there for over a thousand years, and then it vanishes just as we come along? No way. No goddamn way. Something knows we’re here.’

  The bridge crew were looking round anxiously, seeking reassurance from one another. Wilson had been thinking along similar lines himself; quite a loud voice in his head was urging him to run. And don’t look back. The starfield was beginning to reappear around the edges of the barrier as light swept in towards the Second Chance. It gave the rather unfortunate impression of a giant mantrap opening its jaws.

  Wilson turned to Tunde. ‘What’s the Dark Fortress doing?’

  The physics section went into a fevered huddle over their consoles, running analysis routines over the hysradar scans. Wilson watched the results coming through on one of his desk screens, not that he could understand the details, but the overall impression was easy enough.

  ‘There’s still something there,’ Tunde said. ‘Hysradar scan shows it’s smaller than before. We’re probably picking up the outer lattice sphere. Wait – yes, it’s rotating. The shell has gone. And that’s a very strange quantum fluctuation signature inside it. That wasn’t there before.’

  ‘A wormhole?’ Wilson asked.

  ‘No. I don’t recognize it at all.’

  ‘Threat assessment?’

  Tunde gave him a slightly irked look. ‘Nothing obvious. I’ll get back to you on that one.’

  A picture of Dyson Alpha’s planetary system was building up on one of the bridge portals. The two gas-giants were both smaller than Jupiter, orbiting at four and a half AUs and seventeen AUs from their star. While of the three solid planets, the largest had a diameter of fourteen thousand kilometres and orbited one point two AUs out from the sun. The remaining two were both smaller, and in mildly ecliptic orbits a lot further out. They called the innermost planet Alpha Major and focused the starship’s main sensor suite on it.

  ‘My God,’ Sandy Lanier said. ‘Will you look at those readings.’

  Alpha Major’s visual spectrum showed water on a scale that indicated oceans, and an oxygen-nitrogen atmosphere. It was also a strong source of neutrinos. ‘A very heavy level of fusion activity,’ Russell commented. ‘I’d say total power generation exceeds our Big15 worlds combined.’

  ‘What the hell uses that much power?’ Oscar muttered.

  A measurable percentage of it, they discovered, was pumped into communications; throughout the electromagnetic spectrum the planet was shining like a small nova. The starship’s RI began recording the multitude of overlapping signals, but without a key none of its decryption algorithms were of any use.

  The greatest fusion usage was the most obvious to see. Space above Alpha Major was thick with activity. Slender brilliant threads of fusion drives created their own ring nebula, extending from the upper atmosphere out to a million kilo-metres. Not that they ended there, instead they began to disperse. Fleets of ships were accelerating at three or four gees away from the planet, slashing long scars of plasma across the void before finally cutting their engines to coast to destinations across the star system. Hundreds more were on their approach, firing their engines to decelerate into the perpetual swarm circling the planet.

  Over fifty moonlets were in orbit two hundred thousand kilometres out, with knots of small fusion flames wrapped around them as ships came and went. They must have been captured asteroids, their orbit and spacing was too regular to occur naturally. Each one was surrounded by massive industrial stations.

  ‘Don’t they care about their environment?’ Antonia asked. ‘It can’t be safe having fusion ships flying that close to a habitable planet.’

  ‘Those are big ships,’ Anna said. ‘At least the same size as the Second Chance, some are a lot bigger. And their exhaust is helium, they’re probably using boron fusion.’

  ‘Expensive,’ Antonia muttered.

  ‘Depends on your technology level,’ Oscar said. ‘This is not a primitive civilization.’

  ‘Where are the ships going?’ Wilson asked.

  The Second Chance began to expand its observation. They found an astonishing level of technological activity on and around every planet. The two outer solid planets, though cold and airless, were dotted by vast force field domes, artificial habitats whose vegetation matched the spectrum to be found on the landmasses of Alpha Major. Fusion globe suns illuminated each one. Spacecraft were almost as numerous above them as Alpha Major, wrapping the worlds in a perpetual flexing toroid of blazing light. They also had dozens of industrialized moonlets.

  Out among the gas-giants, the pattern was repeated. Every large moon was home to the habitat force field domes, and surrounded by ships and industrialized moonlets. The thin rings orbiting the gas-giants played host to thousands of stations that latched on to the rocky particles, slowly digesting them. On the dozens of outermost moons, rocks that were essentially large asteroids, force field habitats had engulfed them completely. Tightly whorled contortions in the magneto-sphere revealed colossal structures in low equatorial orbit. When the Second Chance’s sensors tracked them, they found they were trailing cables or pipes down into the upper cloud bands.

  As the details appeared on the bridge portal, they made Wilson nostalgic for the future he’d thought he was pioneering back in 2050, the never-happened golden era of humanity’s High Frontier. This was the kind of inter-system society any technological civilization would eventually build if it was somehow cut off from the stars.

  Why would it be cut off, though?

  Three hours after the barrier had vanished, Sandy turned the sensor console over to Anna, though she hung around for a couple of hours to see what developed.

  One of the secondary telescopes was watching the turmoil that was space around Alpha Major. ‘Looks like some ships are heading outsystem,’ Anna said. Eleven streaks of fusion plasma were visible beyond the distance where most of the ships had powered down to coast-flight mode. ‘Accelerating at five gees, and have been for three hours now. That’s one hell of a velocity they’re hitting. I hope they’ve got force field protection. A small molecule can seriously ruin your day at that speed.’

  ‘I’m tracking several similar flights from both gas-giants,’ Jean Douvoir said.

  ‘Any coming our way?’ Wilson asked.

  ‘Not really, sir. One will pass within eight AUs.’

  ‘Safe enough, but keep tracking it. If it alters course in our direction I want to know about it.’

  ‘Aye, sir.’

  ‘Tunde, do you think they’re capable of picking up our hysradar scans?’<
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  ‘I’d say they have the technology to detect quantum wave fluctuations, which might give them an indirect clue we were here. But we haven’t detected any hysradar emissions from inside the star system, so they probably haven’t got a direct detector. There’s also the question of intent. Why would you build a hysradar if you’re confined inside a barrier thirty AUs across?’

  ‘Do they have the technology to build the barrier?’ Wilson asked sharply.

  Tunde grimaced, reluctant to give an opinion. ‘I’d say not. Judging from what we’ve seen, I’d put them on a par with us, with the obvious difference of wormholes. The Dark Fortress is orders of magnitude above anything we’re capable of.’

  ‘That implies the barrier was put up by an outside agency.’

  ‘It’s looking that way, yes.’

  ‘They were confined inside, then. Someone thought they were a threat.’ Wilson turned his attention back to the magnificent astroengineering accomplishments which the sensors were revealing. Given his background, it was hard not to be envious of Dyson Alpha’s civilization. ‘Why?’

  ‘I’m more concerned about why it was switched off,’ Oscar said. ‘Somebody observed us here.’

  ‘That doesn’t make a lot of sense,’ Wilson said. ‘If you were attempting to close off this civilization, why remove the barrier the first time a ship investigates it?’

  ‘They didn’t “attempt” to cut them off,’ Tu Lee said. ‘They succeeded.’

  ‘Which makes switching the barrier off all the more nonsensical.’

  ‘I don’t know what you’re worrying about it for,’ Anna said. ‘There’s a simple way of finding out now.’

  The bridge crew all looked at her. She grinned back, small spiral OCtattoos on her cheeks shimmering a soft silver.

  ‘Ask them,’ she said, and pointed at the portal.

  *

  On the third day after the barrier fell, they used the hysradar to scan the system. Wilson had heard every argument for and against making contact. Most people, himself included, were being cautious, despite what they’d seen of the Dyson aliens. Dudley Bose was keen to start hailing them; while Oscar wanted to turn the Second Chance round and head straight back to the Commonwealth, he was still badly worried by the timing of the barrier coming down.

  It was the first time Wilson really wished they had instantaneous communications back to the Commonwealth. He would have been relieved to pass the buck on this question. Anna was right, they could learn a lot from initiating contact. But now it looked certain the Dyson aliens had been confined, shipboard speculation was heavily focused on the reason. Their civilization was impressive, but not that threatening.

  There were now eighty-three ships heading out from the star system. After three days of continual flight at five gees acceleration the first wave had now travelled over ten AUs, and still more were being launched. The first ships from the outermost gas-giant had almost reached the boundary where the barrier had been.

  Nobody on board the Second Chance could work out what they intended to do once they were outside the thirty AU limit, especially as the ships weren’t designed for interstellar travel. But the crew had spent their time gathering more data on the Dyson Alpha system. It wasn’t just the planets which had been colonized. There were two asteroid belts, one on either side of Alpha Major’s orbit, which were extensively settled. And each of the gas-giant Trojan points, with their broad cluster of medium-sized planetoids, accommodated thriving spaceborne societies. More intriguing – certainly to the physicists – was the swarm of rings, five hundred kilometres in diameter and protected by force fields, which were orbiting three million kilometres above the star’s corona. They seemed to be absorbing the solar wind, siphoning in massive currents of elementary particles that jetted out of the flares and sunspots below them.

  Wilson finally authorized the use of the hysradar to obtain a more detailed chart of the star system and its inhabitants. Nobody was really surprised when it showed tens of thousands of the big ships coasting between planets, moons, asteroid habitats, and the industrial stations. The total was slightly unnerving given how alone the Second Chance was. Also unforeseen were the number of stray asteroids out beyond the second gas-giant they detected which showed signs of colonization and industrial activity. Three of them were only a couple of AUs away. Wilson gave Sandy Lanier, the duty sensor officer, a very hard time for not picking up their neutrino emissions earlier. He paid for it that night, when Anna gave him a lecture on how small the fusion generators were, and how big space in general was. ‘They must be just starting to build on those asteroids,’ she claimed heatedly. ‘If there’s anything big and dangerous close to this ship, our department will spot it for you.’

  He managed to grumble a mild apology, and said they should take a really good look at the nearby asteroids. Having examples of the Dyson civilization so close was an excellent chance to learn what they could without being observed themselves.

  She accepted the apology, and let him kiss and make up. They were getting good at finding innovative ways to use the low gee of the crew ring.

  With a more complete picture of Dyson Alpha’s system established, the starship’s hysradar was focused on Dyson Beta. The range was extreme, but even so the return showed that the barrier around the second star remained intact. It strengthened Oscar’s argument that the removal of Dyson Alpha’s barrier had been triggered by their arrival. Not that anyone could come up with a convincing reason why, and the scenario certainly wasn’t one of the contingency plans so carefully prepared before they let Anshun. All of which left Wilson even more aware of how critical his decisions were now.

  He ordered the sensor department to resume collecting information on the Dyson Alpha system.

  It was while they were scanning the nearby asteroids for high-resolution images that the first firefight broke out a third of the way round the star system. The electromagnetic sensors spotted it first, several large em pulses erupting halfway between the orbits of the two gas-giants. They were quickly confirmed as nuclear explosions. The second barrage broke out as exhaust plumes suddenly streaked out all around the trio of explosions, exposing two squadrons of over thirty ships converging on each other. The fighting had started when they were a million kilometres apart. Now they were all accelerating towards each other at over seven gees. Missiles and gamma lasers turned the shrinking gap into a lethal hurricane of energy. Exploding ships added their fury to the radiation deluge.

  Hysradar swiftly scanned the area in real-time, finding a large, expanding cloud of debris and vapour with several ruined ships tumbling through it. Thirty-two million kilometres away, five colonized asteroids were surrounded by a shoal of ships whose active sensors were probing the battlezone.

  ‘Glad we weren’t there,’ Oscar exclaimed.

  Wilson stared at the display with its crumbling flecks of irradiated matter hurtling apart. It reminded him of the ridiculous slow-motion explosions in the blockbuster films of his youth, where steroidal Hollywood action stars outran the blastwave. ‘Defence,’ he asked slowly. ‘Could our force fields have stood up to that kind of assault?’

  ‘The initial blasts, sir, possibly. But it got pretty hellish in there towards the end.’

  ‘Thank you.’

  He glanced at Oscar, and inclined his head. The two of them went into the senior officers’ briefing room, and opaqued the glass wall. Screens around the long central table glowed blue and crimson from the sensor graphics they were showing.

  ‘I know what you’re thinking,’ Wilson said as he sat on a corner of the table.

  ‘It’s not difficult. I’ve been saying it ever since the barrier came down. We should leave. These developments have pushed us way outside our original mission scenario. We were supposed to be a scouting flight. This is something else entirely.’

  ‘I know, I know.’ Wilson ran his hand back through his hair; it was getting longer than he liked. ‘But we still don’t know why they were confined, and we certain
ly don’t know who or what put the barrier up. We were sent here to find out. That means we haven’t completed our mission, not to my satisfaction.’

  ‘That fight was a damn good indicator why they were penned up in here. It doesn’t come any clearer than that to me.’

  ‘Maybe, but we can’t go home with just an assumption. I need to be certain.’

  ‘It’s not just the Dyson civilization you have to consider, Wilson. Why was that barrier taken down for us? Doesn’t that bother you?’

  ‘Of course it does. But the people who can tell us about the barrier are right here.’

  ‘We can’t ask them, it’s too risky. In our whole history, the human race has only ever let off five nuclear warheads in anger. And they were the most extraordinary, exceptional circumstances. That fight of theirs just saw eight hundred and seventy-two fusion bombs detonating inside of thirty minutes, and half of them had diverted energy output functions. They are dangerous, Wilson. Very, very dangerous.’

  ‘The kind of weapons involved in any conflict are determined by the nature of the battleground and the technology available. If we are attacked out here, I’m quite prepared to use our nukes. It would be an appropriate response. Does my willingness to do my duty make the human race a bunch of dangerous killers?’

  ‘You’re twisting this. I’m on record here: I don’t like this situation. It is my opinion we should leave.’

  ‘We can’t. For all it’s an unexpected outcome, this is why we’re here. Discovery and opportunity, Oscar. We can’t turn our back on it. That would be less than human. I’m going to authorize a remote investigatory contact.’