Starplex

by Robert J. Sawyer

  "But the Milky Way has spiral arms," said Lianne.

  Jag turned to her. "Yes, without question, the Milky Way today has spiral arms. And, just as surely, I can now say that when it was six billion years younger, it did not have spiral

  "How can that be?" asked Thor.

  "That," said Jag, "is a vexing question. I confess that I would have expected a Milky Way even half its present age to still have arms."

  "Okay," said Keith. "So the Milky Way gains spiral arms sometime in the interim."

  "No, it is not okay," said Jag, his bark returning to its usual sharpness. "In fact, it has never made any sense. We've never had a good model for galactic spiral-arm formation. Most models are based on differential rotation--the fact that stars near the galactic center make several orbits around the core in the time it takes for those farther out to complete just one. But any arms that resulted because of that should be temporary phenomena, enduring at most for a billion years. Oh, we should see some spiral galaxies, but there is no way that three out of every four large galaxies should be spirals--which is the ratio we actually observe. Ellipticals should far outnumber spimls, but they do not."

  "Obviously, then, there's a flaw with the theory," said Keith.

  Jag lifted his upper shoulders. "Indeed. We astrophysics types have been limping by for centuries with something called 'the density-wave model' for explaining the abundance of spiral galaxies. It proposes a spiral-shaped disturbance that moves through the medium of a galactic disk, with stars getting caught up in it--or even being formed by it--as the wave rotates. But it has never been a satisfactory theory.

  First, it fails to account for all the different types of spiral forms, and, second, we don't have a good answer as to what would cause these imagined density waves in the first place. Supernova explosions are sometimes cited, but it's just as easy to model such explosions canceling each other out as it is to get them to build up long-duration waves." He paused. "We've had other problems with our galaxy-formation models, too. Back in 1995, human astronomers discovered that distant galaxies, observed when they were only twenty percent of the current age of the universe, had rotational rates comparable to what the Milky Way has today--that's twice as fast. as they should have been rotating at that age, according to theory."

  Keith thought for a second. "But if what we're seeing right now is correct, then spiral galaxies like ours must somehow form from simple disks, right?"

  Another lift of the Waldahud's upper shoulders. "Perhaps.

  Your Edwin Hubble proposed that galaxies each start as a simple sphere of stars, gradually spin out into a flat disk, then develop arms that open up more and more over time.

  But although we now have observational proof that that sort of evolution does indeed happen"--he gestured at the disk of stars in the glowing frame--"we still don't have an explanation for why the evolution takes place, or why the spiral structures persist."

  "But you say three quarters of all large galaxies are spirals?" asked Lianne.

  "Wellll," said Jag, PHANTOM translating a hissing bark as a protracted word, ."actually, we don't know much directly about the ratio of elliptical to nonelliptical galaxies in the universe at large. It's hard to make out structure in dim objects that are billions of light-years away. Locally, we see that there are many more spirals than there are ellipti-cals, and that spirals contain a preponderance of young blue stars, whereas our local ellipticals contain mostly old red stars. We've assumed, therefore, that any vastly distant galaxy that showed lots of blue light--after correcting for redshift, of course--was a spiral, and any that showed mostly red was an elliptical, but we really don't know that for sure."

  "It's incredible," said Lianne, looking at the image.

  "So--so if that's how it looked six billion years ago, then none of the Commonwealth homeworlds yet exists, right? Is there--do you suppose there's any life in the galaxy now?"

  "Well, 'now' is still 'now,' of course," said Jag. "But if you're asking if there was any life in the Milky Way hack when that light started its journey to us, I would say no.

  Galactic cores are very radioactive--even more so than we used to think.

  In a large elliptical galaxy, such as we're seeing here, the whole galaxy is essentially the core. With stars that close together, there would be so much hard radiation everywhere that stable genetic molecules wouldn't be able to form." He paused. "I guess that means it's only middle-aged galaxies that can give rise to life; young, armless ones will be sterile."

  There was silence on the bridge for a time, broken only by the gentle hiss from the air-circulating equipment and the occasional soft beep from a control panel. Each person contemplated the small fuzzy blot of light that one day would give rise to all of them, contemplated the fact that they were farther out in space than anyone had ever been before, contemplated the vastly empty darkness all around them.

  Six billion light-years.

  Keith remembered reading about Borman, Lovell, and Anders, the Apollo 8

  astronauts who had circled the moon over Christmas of 1968, reading passages from Genesis back to the people on Earth. They had been the first human beings to get far enough from the homeworld so that they could cup it in an outstretched hand. Maybe more than any other single event, that view, that perspective, that image, had marked childhood's end for humanity--the realization that all their world was one tiny ball floating against the night.

  And now, thought Keith, maybe--just maybe--this image was the one that marked the beginning of middle age: a still frame that would become the frontispiece of volume two of humanity's biography. It wasn't just Earth that was 'tiny, insignificant, and fragile. Keith lifted his hand and reached out toward the hologram, cupping the island of stars in his fingers. He sat silently for a long moment, then lowered his hand, and allowed his eyes to wander over the overwhelming dark emptiness that spread out in all directions.

  His gaze happened to pass over Jag--who was doing exactly what Keith had done a moment ago, using one of his hands to cup the Milky Way.

  "Excuse me, Keith," said Lianne, the first words spoken by anyone on the bridge for several minutes. Her voice was soft, subdued, the way one would talk in a cathedral. "The electrical system is repaired. We can launch that probe anytime you like."

  Keith nodded slowly. "Thank you," be said, his voice wistful. He looked once more at the young Milky Way floating in the darkness, and then said softly, "Rhombus, let's have a look at what's going on back home."

  Chapter XX

  "Launching probe," said Rhombus.

  In the holo bubble, Keith could see the silver-and-green cylinder moving away from the ship, illuminated by a tracking searchlight on Starplex's hull. It looked out of place against the fuzzy splotches of distant galaxies. Soon the probe touched the shortcut and disappeared.

  "The mn should only take about five minutes," said Rhombus.

  Keith nodded, trying to contain himself. He didn't know which he wanted more: to have the probe report that it had detected Rissa's transponder--meaning the Rum Runner was at least still intact--or for it to report nothing, meaning the probeship might have made it through the shortcut to safety.

  Time passed, and Keith's nervousness grew. A watched pot never boils, but . . .

  He looked up at the trio of clocks floating in space above the hidden port-side door. "How long has it been?"

  "Seven minutes," said Rhombus.

  "Shouldn't your probe be back by now?"

  Lights moved up the Ib's web.

  "Then where the hell--"

  "Tachyon pulse!" announced Rhombus. "Here it comes."

  "Don't wait until it's docked," said Keith. "Download the data by radio and display it."

  "Doing so with delight," said Rhombus. "Here we go."

  The probe's scan was low resolution, and video, rather than holographic.

  A part of the all-encompassing bubble was framed off in blue, and playback of the flatscreen images the probe had recorded began to appear.
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  "What the--?" said Keith. "Rhombus, did you use the correct angle of approach?"

  "Yes--to within a fraction of a degree."

  Jag said a Waldahudar swear word. By default, PHANTOM didn't translate profanity, but Keith felt like swearing himself. "That's not where we came from," he said.

  Jag's fur was motionless. "No," he said. The image in the screen showed tightly packed red stars. "At a guess, I'd say it's not even anywhere in the Milky Way. That looks like the inside of a globular cluster. There are dozens associated with CGC 1008, so it might even be one of those."

  "Which means--"

  "Which means," said Thor, lifting his hands from the helm console, "that we can't go home. We don't have the correct address."

  "The latitude/longitude coordinate system must not work the same way over such great distances," said Lianne.

  Keith's voice was small. "Even at full hyperdrive--" Jag snorted.

  "Even at full hyperdrive, to cover six billion light-years would take two hundred and seventy million years."

  "All right," said Keith. "We'll try sending probes through in a search pattern. Rhombus, start by piercing the tachyon sphere around the shortcut at the north pole, then work your way down, trying again at every five degrees of latitude and five degrees of longitude. Maybe, if we're really lucky, we'll see something we recognize in the scans they bring back."

  Rhombus began launching probes, but it soon became apparent that they were all going to either the globular cluster, or to another region of space where the sky was dominated by a ring-shaped nebula.

  "From the point of view of this shortcut," said Rhombus, "there are only two other active shortcuts. I suppose that means we're lucky our initial probe came back to us--it only had a one-in-two chance of doing so."

  "Not much of a choice, is it?" said Keith. "Here on the periphery of a black hole in intergalactic space; off in a globular cluster--presumably full of old, lifeless stars; or over to that ring nebula."

  "No," said Jag.

  "No what-?"

  "No, we cannot be limited to those choices."

  Keith let out a sigh of relief. "Good. Why not?"

  "Because the God of Alluvial Deposits is my patron," said the Waldahud.

  "She would not abandon me."

  Keith felt his heart sink. He stopped himself before he snapped out something nasty.

  "There has to be a way back," said Jag. "We came here, and therefore we must be able to return. If only we--"

  "Speed!" shouted Lianne.

  Keith looked at her.

  "Speed!" she said. "We went through the shortcut at very high speed.

  Perhaps the velocity range at which you enter a shortcut selects which other family of shortcuts you have access to. We've always previously done it at very low relative velocities in order to avoid impacts.

  After all, one does go through a shortcut blind, not knowing for sure what's on the other side. But this time, we whipped into it at substantial fraction of light-speed. We may have keyed into another level of shortcuts by doing so."

  Keith turned to Jag. He lifted all four shoulders. "It's as good an explanation as any."

  "Rhombus, launch another probe," said Keith. "Put it on a long trajectory that will let it accelerate to the same speed we were at when we passed through the shortcut, and aim for the exact latitude and longitude that corresponds to where we came from."

  "Doing so with transcendent joy," said the Ib.

  The probe was launched, built up speed, pierced the shortcut. They all held their breaths. Even Rhombus's pump, which operated without guidance from the pod, apparently sensed that something important was happening.

  Its central orifice temporarily halted its constant sequence of open, stretch, compress, and close.

  And then the probe returned. Rhombus's ropes whipped his console, making loud slapping sounds as they did so, and the framed-off area filled with the probe's recorded images.

  Thor was grinning from ear to ear. "I never thought I'd be glad to see that thing again," he said, jerking a thumb at the image of the green star.

  Keith breathed a long sigh of relief. "Thank--thank the God of Alluvial Deposits."

  "According to the probe's hyperscope, the darmats have moved well away from the exit point," said Rhombus.

  "Excellent. Thor, take us home. Execute the course we discussed earlier. I want to have a word with Cat's Eye."

  Chapter XXI

  Starplex moved through the intergalactic abyss toward the shortcut.

  The ship--seeming minuscule amidst all the emptiness--gathered speed as it approached, Thor revving up the thrusters. When it touched the shortcut, a ring of violet fire passed over the vessel as it traversed six billion light-years -- 60,000,000,000,000,000,000,000 kilometers--in the blink of an eye. There was a spontaneous cheer from those on the bridge as the holographic bubble was filled again with countless stars.

  Keith felt his eyes stinging, the way they had the last time he'd returned to Earth.

  Thor immediately began making manual adjustments; they hadn't been monitoring the green star long enough to know its exact trajectory away from the shortcut, and his guess of where it would be was somewhat off.

  He soon had the ship settled into the parabolic course Keith wanted--a much wider parabola than their previous passing, avoiding any dangerous proximity to the green star, which now once again dominated the holo bubble.

  "Scan for the Rum Runner's transponder," said Keith.

  "Doing so," said Lianne. But then, a moment later, "I'm sorry, Keith.

  There's nothing."

  Keith closed his eyes. She could be safe, he told himself, she could have gone through to another exit, she could-- "Tachyon pulse!" said Rhombus in what PHANTOM translated as a shout.

  Keith swiveled around to look at the shortcut, now swelling into a purple-limned shape--in the exact cross sectional outline of a Commonwealth probeship.

  "It's the Rum Runner!" crowed Thor.

  "Incoming signal," said Lianne. She touched keys and a hologram of Rissa's beaming face appeared inside a floating frame.

  "Hello, everyone," said Rissa. "Fancy meeting you here."

  "Pdssa!" said Keith, rising to his feet.

  "Hello, darling," said Rissa, smiling radiantly.

  "Rhombus," said Keith, "can they dock with us, given the course we're on?"

  "They can if I give them a tow with a tractor beam."

  Keith was grinning widely. "Please do so!"

  "Okay, guys," said Rhombus, "prepare to be grabbed by a tractor."

  Longbottle's gray face popped up next to Rissa's. "Pre- pared are we!

  Home we come!"

  "Locking on," said Thor.

  "Thor," said Keith, "do you have a fix on Cat's Eye?"

  "Yes. He's about ten million klicks ahead, at about nine o'clock to the green star."

  "I've located a vacant frequency in the darmat babble, in case you want to talk to him," said Lianne. "Somebody must have left the conversation recently."

  "Excellent," said Keith. "Keep track of it. As soon as Rissa's back on board, I'll want to open communication."

  "We'll have the Rum Runner in docking bay seven in about three minutes,"

  said Rhombus.

  Keith was anxious as hell. He tried to hide it by checking status reports on his monitor screens, but his mind wasn't registering the words. At last, the' starfield split and Rissa appeared, framed by the corridor beyond. Keith ran to her, and they hugged, then kissed. The rest of the bridge crew cheered as she entered. A moment later, Longbottle popped up in one of the two open pools. Rissa knelt down beside him and rubbed his bulging forehead. "Thanks for getting us home safe and sound, buddy," she said.

  "We're doing a quick parabolic path," Keith said to them.

  "I don't think the darmats can grab us this time, but I want to communicate with them--find out why in the hell they attacked us."

  Rissa nodded, stood up, kissed Keith once more, then moved over
to her workstation. She pressed keys, calling up the translation program.

  "Do we still have a vacant frequency?" asked Keith.

  "Yes," said Lianne.

  "All right. Let's jump into the conversation. Lianne, open a channel from my console with automatic translation, but put a five-second delay in before you send whatever I say."

  He looked at Rissa. "I'll speak directly to Cat's Eye, but if I say anything wrong or something that you don't think will translate properly, jump in, and we'll reword the message before it goes out."

  Rissa nodded.

  "Ready," said Lianne.

  "Starplex to Cat's Eye," said Keith. "Starplex to Cat's Eye. We are friends. We are friends." Keith glanced at a counter. At light-speed, it would still be thirty-five seconds before the message reached Cat's Eye, and almost that long again before any reply would arrive.

  But no reply came. Keith waited an extra full minute, then another.

  He touched a key and tried again. "We are friends."

  Finally, after a forty-second delay in addition to the round-trip signal time, a reply came through. Just two words, in a curt French accent:

  "Not friends."

  "Yes," said Keith. "We are friends."

  "Friends not hurt," came the reply, with no delay beyond that caused by transmission times.

  Keith was taken aback. Had they somehow hurt the darmats? It was almost inconceivable that they could injure such giant creatures.

  Still . . . perhaps the sampling probes had caused pain. Keith didn't have the slightest idea how to apologize; the vocabulary Rissa had built up didn't deal with such concepts.

  "We did not mean to hurt you," said Keith.

  "Not directly," said Cat's Eye.

  Keith spread his hands and looked around the bridge.

  "Anybody understand that?"

  "I think he means whatever injury we caused wasn't a direct injury,"

  said Lianne. "We didn't hurt them, but hurt--or were going to hurt--something that was important to them."

  Keith touched the transmit key. "We intend no injury to anything. But you--you deliberately tried to kill us."