Center of Gravity

by Ian Douglas

  Reluctantly, the guard began backing toward the door. Vrilkmathav rippled through first, then waited for the guard to enter the airlock as well. Reaching up, it plucked one of the respirator masks designed for humans from the wall. The human captive struggled, trying to pull the mask off, but once it was in place, a touch of one tentacle sealed it to the creature’s integument.

  Humans and Jivad Rallam breathed almost identical oxygen-nitrogen atmospheres, but Jivad required a higher percentage of carbon dioxide—almost 2 percent by volume—than did humans, and Vrilkmathav’s respirator added the missing CO2 when it entered the human den. If the human didn’t wear the mask to filter out the excess CO2 now present throughout the rest of the base, it would swiftly lose consciousness and die. Humans didn’t seem to react well to carbon monoxide, either, or to several other trace compounds in the standard Jivad Rallam atmospheric gas mix.

  “What . . . what want you from us?”

  Vrilkmathav swiveled all four eyes down to look at the human in its grasp. Moisture was streaming from its eyes—a biological lubricant of some sort that Vrilkmathav had noted in other humans when they were in extreme pain or psychological duress. The fluid tasted strongly of sodium chloride when it touched the Jivad’s tentacle.

  This one spoke Drukrhu, then, and fairly well, better than the dead male inside the den.

  “In your case,” Vrilkmathav said, “we wish to explore the artificial devices implanted within your . . . erj . . . erj . . .” It didn’t have the technical word.

  “ ‘Cerebral cortex,’ ” the Sh’daar Seed within its primary brain suggested.

  “Ah. The devices within your cerebral cortex.”

  The atmosphere stabilized at Jivad norm, and the outer door liquefied. Vrilkmathav rippled through the black curtain of rigid liquid.

  “We have noted,” it continued, “that these devices appear to be similar to something we call ‘the Sh’daar Seed,’ which is a microscopic set of circuits that enable us to communicate with the masters. If that similarity, in fact, exists, it may be that we will be able to create devices enabling you to experience a direct interface with the Sh’daar. We have dissected the brains and brain implants of several of the other humans—but all were male. We now wish to see if there are morphological differences between human females and males, and if the electronic implants you carry are different as well.”

  Vrilkmathav wasn’t sure how much of what it said was understood by the human; the creature’s grasp of the artificial Agletsch language seemed less than complete. It must have understood some of what Vrilkmathav said, however, judging by the way its struggles to escape the Jivad’s grasp increased.

  Its shrieks sounded so much like those of injured Jivad Rallam young.

  There were times when Vrilkmathav truly hated its assignment here.

  An alarm shrilled through its Seed. “What is happening?”

  Several vrith passed before it received an answer. The Sh’daar Seed didn’t so much speak as communicate through impressions, through a kind of knowing. An enemy fleet of warships had just appeared on the outskirts of this system. The energies now being detected by Turusch, H’rulka, and Jivad ships were many thavii old now, and likely there were fighters inbound on the very heels of those energy wavefronts.

  Vrilkmathav spun about sharply, thrusting the human at one of the armored guards. “Quickly!” it said. “Put this back with the others! Gently, idiot! Don’t hurt it! Put it away and join your unit! We are under attack!”

  Jivad neuters were warriors before they were scientists—a function of their nurturing and protective roles in Jivad Rallam biology. It hurried off toward the ship bays as swiftly as its roiling tentacles could carry it.

  Chapter Fourteen

  29 January 2405

  Alchameth-Jasper Space

  Arcturus System

  1147 hours, TFT

  From Gray’s point of view, the entire flight, from launch to objective, had lasted scarcely twenty minutes.

  As a ship approached the speed of light, time dilation did strange things to time on board, slowing its passage to a fraction of the normal rate. Accelerating at fifty thousand gravities, the fighters had reached 99.9 percent of the speed of light in just under ten minutes, with time passing more and more slowly as they neared c. For the pilots of the three squadrons of the advance strike force, the following 160 minutes in the outside universe was for them just 7 minutes, 9 seconds. By skimming across 20 AUs at just less than c, Gray and the others had lost over two and a half hours as the rest of the universe measured time—were two and a half hours younger than those left behind in the relatively slow-moving battlegroup.

  As the three Starhawk squadrons decelerated into circum-Alchameth space, subjective and objective times began to fall back into phase. Their weirdly distorted view of the surrounding cosmos, a starbow of light ringing the blackness around each fighter thirty degrees forward of center, began to smear back into the accustomed stars of non-relativistic flight.

  Gray tried to shove aside the rising fear, the memories of nightmares—tried, and failed.

  He’d been in the Arcturus System before. Fourteen months earlier, the Star Carrier Ticonderoga and seven escorts had responded to a courier request for help. Gray, fresh from a training squadron at Oceana, had been the FNG in VF–14, the White Furies, and as the Tike had entered the Arcturus System, he’d been spin-deployed on Combat Space Patrol.

  The Turusch had been waiting for them. Probably, they’d noted the escape of the courier and guessed that Confederation reinforcements would arrive within a few days. Several enemy task groups had been scattered across the Arcturian system, and one, by chance, had been less than thirty light minutes from the Tike’s emergence point.

  For six hours, the Ticonderoga had fought off waves of enemy fighters, ship-killer missiles, and gunships. She’d limped clear of the battle at last, shield cap breached and spewing ice crystals, screens gone, most of her weapons smashed, three quarters of her crew dead or dying of radiation poisoning. It had been a miracle that she’d been able to slip into Alcubierre Drive and escape, a miracle that the Turusch had not pursued her.

  Gray had been back on board rearming his ship. He was one of just two White Furies to survive the Battle of Arcturus Station.

  This time, of course, it was different. A powerful carrier battlegroup was launching an alpha strike at an enemy that did not know they were coming. Three fighter squadrons were hurtling into the system just behind the wavefront announcing their arrival. This was payback, not a repeat of the disaster of fourteen months ago.

  But Gray still felt the fear. “Pucker factor,” the pilots called it, the feeling that you were gripping the acceleration seat of your fighter so tightly with your ass that you were never going to be able to let go.

  He focused on the immediate, routine tasks at hand, keeping his mind busy on other things. In particular, he studied again the scans downloaded from the ISVR–120 probe that had passed through this star system a month ago, noting the ship positions and tentative identifications. Much could have changed in a month, of course, but ONI’s assessment held that the strategic picture in the Arcturus system ought to be pretty much the same. If anything, there might be fewer Turusch heavies here, as they prepared to move against Sol.

  Long-range sensor scans from the emergence point had definitely pinpointed the two Beta-class battleships spotted by the reconnaissance probe, still close beside Arcturus Station. There was also a scattering of smaller vessels, though how many and where, exactly, was tough to pin down from 21 AU out. Their power-plant leakages tended to be lost in the glare from the local star and in the belts of hard radiation surrounding Alchameth.

  Gray gave a silent command, and battlespace monitors—finger-sized robots with high-grav drives—sprayed from his Starhawk, spreading out with monitors from other fighters to create a cloud of electronically interconnec
ted microdetectors monitoring optical, radio, neutrino, and gravitic wavelengths throughout circum-Alchameth space.

  They would know for sure in another minute or two whether the tactical situation had changed at all.

  The fighter’s AI continued to slow the Starhawk with an unfelt tug of fifty thousand gravities. The starbow continued to dissipate, as space took on its normal and accustomed non-accelerated shape.

  Arcturus blazed ahead and to the left, golden orange and brilliant, and Alchameth was a bright star directly ahead. As the fighters continued dropping deeper in-system, the star became a tiny orange crescent, expanding swiftly as the fighters continued to slow.

  “Here we go, Dragonstrike,” Allyn’s voice called. “Record sensor data and transmit on auto, Channel 3294.”

  Everything Gray’s fighter picked up either from the battlespace monitors or with its own sensor array would be streamed outward, where it would be captured by the incoming America and other CBG vessels and fed into their tactical displays, updating them each tenth of a second.

  So far, it looked like the alpha strike had caught the enemy sleeping.

  A dozen large alien ships clustered near the Earthlike moon, Jasper. Largest were the two Betas, converted asteroids massing some tens of millions of tons each—oblong, dusty-looking potato shapes pocked with numerous craters and showing constellations of star-point lights and the bristle of heavy weapons emplacements. They appeared to be hanging close to Arcturus Station, pacing its two-hundred-kilometer orbit around Jasper. Eight smaller ships, Juliet- and Kilo-class Turusch heavy cruisers, floated in the asteroids’ shadows.

  Two more were unidentified, their shapes not listed in the warbook residing in Gray’s Starhawk fighter. They were large, however, as large as the Juliets, and had already been tagged as “Red-One” and “Red-Two” on the tactical display net.

  There were lots of smaller vessels scattered across the tactical display as well. Gray’s fighter had pinpointed fourteen Turusch destroyers and frigates so far, and more, almost certainly, were hidden by Alchameth’s broad and color-banded bulk.

  “Bravo-One and Bravo-Two are the primaries,” Commander Allyn’s voice said over the fighter comnet. “Hit them, then fire at will. You are not clear to engage Arcturus Station, repeat, not clear to engage the station until we have solid telemetry on who’s inside!”

  That part of the operation had been endlessly discussed and dissected in tactical simulations during the voyage out from Sol. It had been fourteen months since the first Battle of Arcturus Station, but there was still a chance, a small one, that there were humans still alive and on board. How the incoming battlegroup would engage the ships in circum-Alchameth space depended in large part on whether there were human POWs still on the station after all of this time.

  “Strike Nine, Kraits armed,” Gray reported. “Target lock! Fox One!”

  A VG–10 Krait smart missile streaked from beneath the black folds of his Starhawk’s keel, its tiny high-G grav drive radiating a dazzling star of dumped heat and light. Other smart missiles began arcing in from the other fighters, their contrail-wakes curving as they swooped toward their behemoth targets. Answering contrails punched out from the enemy ships, streaking out toward the fast approaching fighters.

  “Evasive maneuvers!” Allyn commanded, and the fighters began jinking, using brief, intensely focused singularities to port and starboard, above and below, to keep their vectors from becoming predictable. As the enemy missiles closed, the Confederation fighters fired sand canisters—containers of refractive particles used as point-defense against both missiles and energy beams.

  White light blossomed in the silence of hard vacuum, a Krait detonating against one of the Beta battleships. Its shields were up, twisting space to deflect the blast, but enough heat and hard radiation leaked through to boil the gray, pocked surface. A second detonation pulsed against the night, knocking out shields, sending a gout of white-hot gas spewing out into space. Other missiles fell into the Turusch fleet, some striking the asteroid battleships, others homing on the cruisers. Within seconds, local space was an intolerably brilliant cascade of expanding fireballs. “Nailed ’em!” Lieutenant Donovan cried.

  “Good shooting, Dragonfires!” Allyn called. “Break and engage!”

  All three fighter squadrons were scattering now, each ship continuing to jink to frustrate the enemy’s defensive fire.

  For many years, strategic wisdom had declared that piloted space-fighter craft were an anachronism, a holdover from the long-gone era of jet-powered fighters launching from oceangoing aircraft carriers and about as relevant to space warfare as ancient oared triremes. The physics of interstellar combat, however, made them inevitable.

  Capital ships—the carriers, battleships, railgun cruisers and destroyers of the fleet—had a maximum acceleration of around five hundred gravities, a limit imposed partly by the available power from current quantum energy taps, and partly by their sheer size and mass. And because the space-warping fields of their Alcubierre FTL drives required that local space be “flat,” undistorted by gravitational masses, ships had to exit their FTL bubbles far from a local star—generally twenty to fifty astronomical units out.

  In high-acceleration boost mode, a Starhawk fighter massed just twenty-two tons and measured seven meters in length, not counting the long field-bleed spike astern. Low mass and small dimensions let them accelerate at rates up to a hundred times greater than capital ships, which meant they could reach 99.9 percent of the speed of light in something just under ten minutes.

  A cloud of high-G fighters, then, could be in among an enemy fleet deep in-system twenty minutes after the light bloom of capital ships entering normal space on the system’s outer perimeter. Highly maneuverable, they could get in close and cause crippling damage to even the largest of enemy capital ships. Even a Turusch Alpha-class battleship, a converted asteroid massing trillions of tons, could be damaged severely enough by fighters that it became an easy mark for the heavy weapons of the battlegroup when it arrived hours later.

  As for why fighters still had human pilots rather than AIs . . . the principal reason had to do with the prejudices of the military and political decision makers back home. Artificial Intelligences could pilot small ships—very small ships, in fact—independent of human oversight, but most humans still feared what might happen if AIs were given unrestricted and unsupervised control of megatons of destructive power.

  And so human pilots continued to squeeze themselves into high-G fighters and let themselves be accelerated into combat, engaging in deadly knife fights with far larger and more powerful warships. Gray adjusted his ship’s current trajectory to skim past an enemy Tango-class destroyer directly ahead. His fighter’s AI handled the split-second timing of the combat pass, but it was Gray who gave the engage order.

  He had an instant’s impression of the Turusch destroyer’s hull, painted in jagged patterns of green and black as it loomed ahead, then flashed past to port. Gray’s AI pivoted the Starhawk, holding its Gatling RFK–90 KK cannon on-target through the pass, loosing a stream of magnetic-ceramic jacketed slugs at a cyclic rate of twelve per second. Each round, with a depleted uranium core massing half a kilo traveling at 175 meters per second, carried a savage kinetic-kill punch as powerful as a tactical nuke as it ripped through hull metal and defensive shields. As the destroyer fell astern, gouts of light erupted from its flank; water from its reaction-mass tanks spilled into space, freezing instantly in a swelling cloud of glittering particles of ice.

  “Dragon Five, Dragon Nine, this is One,” Allyn’s voice called over the tactical link. “You’re both on close approach to the station. Drop a couple of ears on it, okay?”

  “Copy that,” Gray replied.

  “Roger,” Lieutenant Collins added. “Stay out of my way, Prim.”

  Gray bit off an angry response, deciding to ignore the taunt. He palmed the programming touchpad an
d readied a VR–5 reconnaissance probe.

  Slightly larger than a human head, the VR–5 remote-scan sensor probe was identical to a battlespace remote probe, but with different programming. A Starhawk carried a battery of four VR–5s, which could be selectively programmed for specific missions.

  By chance, both Gray’s and Collins’ fighters would be falling past Arcturus Station in another few minutes, Gray’s Starhawk passing less than fifty kilometers from the structure, Collins about seventy. Gray programmed two of his VR–5s, and directed his AI to release them at the optimum launch point for intercepting Arcturus Station.

  Then a trio of tactical nuclear weapons detonated a few kilometers astern, and Gray was very busy accelerating clear of the blast fronts, high-velocity expanding shells of charged particles and hot gas that could overwhelm a fighter’s defenses if they hit the ship’s shields and screens at close range.

  There were fighters out there, punching in through the gas shells—a pair of Turusch Toads.

  Toads were heavy fighters, squat and ugly, thirty meters long, fifteen thick, and massing over fifty tons. They didn’t change shape like Starhawks and other more modern Confederation fighters, but they were more powerful, could accelerate more quickly, and could survive the detonation of a tactical nuke at close range. Gray flipped his fighter end for end, bringing his PBP–2 to bear on the nearest one.

  The StellarDyne Blue Lightning particle beam projector mounted on his Starhawk’s spine charged, then fired. Variously called a PBP, a CPG for “charged-particle gun,” and, more commonly, a “pee-beep,” the weapon loosed a tenth-second gigajoule burst of tightly focused protons, a straight-line lightning stroke that could overpower enemy radiation screens and boil off tons of surface armor. Gray’s first shot knocked down the lead Toad’s forward screens, and he followed up with a burst from his KK Gatling, using the Turusch ship’s higher relative velocity against it. The explosion flooded nearby space with the harsh glare of evaporating grav singularities, and forced the second Toad to break off its approach.