Agnes had upgraded the probes since Richard III had been launched. There were three generations of probes now; the third and newest sported a more efficient matter-antimatter propulsion system and was faster than the previous generations. Because of this, data from second-generation probe Desdemona, bound for Epsilon Eridani, would reach Agnes later than data from thirdgeneration probes like Apemantus and Beatris, launched toward the more distant 61 Cygni and Epsilon Indi.
“Are all fifteen probes telling us this?” asked Agnes.
“No, we’re only getting data from the first ten. The last five haven’t reached maximum velocity yet.”
“If our five newest probes aren’t traveling fast enough to gather this data, it’s going to be less precise than I hoped. Charon, Triton, and Shantak II are corroborating the probe data. But those facilities were built to detect specific phenomena. They’re not broad-spectrum observation sites.”
“True, they’re not,” Aguri said. “The big interferometers on Charon and Triton look for gravity wave sources by comparing time differentials across data. But the interferometers themselves aren’t specialized. It’s their data-processing infrastructure. They’re doing narrow-band analysis geared to what they’re looking for. But the newest processors can handle a much wider range of frequencies.”
“So you used those processors to go back and review the data to verify your hypothesis?”
All interstellar probes, beginning with Richard III, were equipped with an advanced AI. For the first few years of their missions, the AIs could be monitored and, within limits, upgraded remotely, especially if the AI encountered a problem beyond its capacity. Richard III’s AI was upgraded not far from the solar system. The data from each probe was applied to the next, making each one more “experienced” than the last.
This increasing sophistication had led to an unexpected discovery. The newest probes were capable of accelerating to around thirty percent of light speed. At this speed, starbow effects—relativistic Doppler shifting of starlight—were not yet pronounced. They could only be detected with specialized sensors. Confirmation of the starbow effect was an important goal of all interstellar probes, beginning with Richard III. Astronomers hoped that relativistic Doppler effects would open up new methods of observation.
The ability to upgrade AIs after launch played an important role in the effort to gather starbow data. Now Aguri had discovered that the effect applied to gravity waves as well as electromagnetic waves.
Unfortunately, the need to shield the fast-moving probes against interstellar dust prevented them from serving as long-range laser interferometers. Instead, the probes observed minute frequency shifts in starlight caused by gravity. Careful analysis of the data confirmed that starbow effects applied to gravity waves.
Aguri had boosted the accuracy of the probes’ sensors by networking them. The results were confirmed by the large interferometer arrays on Triton and Charon and by Shantak II, the gravity-wave observation platform half a light-day from the Sun. Collating all this data would eventually lead to new ways of utilizing gravity waves in astronomical research.
“And this tells you that gravity wave transmissions are going to other points in the galaxy?” said Agnes.
“That’s what the data suggests. That implies the existence of nonhuman intelligences.”
“Atwood said the same thing. During the standoff on Shantak II, he never stopped observing. He’s completely sold on the idea of nonhuman civilizations. Has the bug bitten you too?”
“Atwood is a strange bird, but he’s a first-rate scientist. The trouble we had with the Terrans put an end to the ultra-long-baseline gravity-wave observation project. But Atwood’s data and his hypothesis seem solid to me.”
Agnes peered at the girl with narrowed eyes. She had practically raised both Aguri and Atwood. They were the first members of Agnes’s Mafia, which had led some parents to joke that giving one’s child a name beginning with A was essential for a future as a first-rate scientist.
“I’ll concede that the data points in the direction you say. But don’t you think it’s premature to pin extraterrestrial intelligence on coherent gravity waves? After all, why use gravity waves? They penetrate interstellar dust and gas better than radio waves, but on the whole they’re too weak. Radio waves are technically far better for communication.
“So we seem to have detected gravity wave transmissions. What about two centuries of monitoring for intelligent signals in the electromagnetic spectrum? We’ve found nothing. And even if we assume this is an intelligent signal, how do you account for the complete absence of similar electromagnetic signals? Of course, we’re not in a position to guess how an alien civilization would choose to communicate, but still…”
“Maybe it’s more natural for them to use gravity waves. Maybe their biology makes it easier. You can’t rule that out.”
“What kind of life-form would find it natural to use gravity waves?”
“Well, for example, a life-form like the one you speculated about, once upon a time.”
“How in the world did you find out about that?”
“Your paper on the nanomachine experiment is in the public domain.”
“But there must be as many AADD experimental papers as there are stars in the galaxy,” Dr. Agnes said.
“Yes, but the revolutionary ones are as scarce as the number of moons in our system. I didn’t find the math that hard to follow. Well, okay, I had to pay careful attention to some sections.”
The relationship between the two women was more like that of an older sister and a younger sister than research advisor and student—sisters bound by shared outlook and vision instead of blood. They still lived in the same complex in Port Shiva, though Agnes traveled so often now that Aguri only saw her rarely. AADD’s family units often followed this pattern; Agnes’s Mafia was no different.
Still, Agnes wouldn’t have expected Aguri to read all of her old papers. It certainly wasn’t essential for her work. But she understood why Aguri had made the effort—she wanted to know as much about Agnes as she could. Perhaps Aguri idolized her. Agnes had nursed similar feelings toward some of her teachers.
“To be honest, something else made me remember that report just now,” said Aguri. “If the galaxy is filled with gravity wave transmissions, there must be evidence in Sol System. Gravity wave observation doesn’t have the history that radio astronomy does, but we do have lots of data.”
“But Atwood is the only one reporting signals that seem to be coming from an extraterrestrial civilization. Application of the gravity-wave Doppler shift to observational technique is still in its infancy. You may have trouble getting repeatable results.”
“Agnes, there’s corroboration. I found it in an old paper from 2123, right after they started work on the AAD.”
“2123…” Agnes caught her breath. The year was engraved in her memory. Everything started in 2123.
“It was before Chandrasekhar Station was complete, when all they had was the ring around Kali—Ouroboros. You know the story. The ring’s AI was convinced it had detected gravity waves. The result was nearly a catastrophe,” Aguri said.
Catherine Sinclaire had been Agnes’s instructor, and she had been on Ouroboros when it happened. Catherine had been young at the time—almost a child, really. Agnes knew her report of the incident by heart. Catherine and her partner Tatsuya had told her the story many times; reliving it together had become a kind of family tradition.
“Yes, I know about that incident,” said Agnes.
“Do you know what I thought when I read your paper on the experiment?” Agnes didn’t answer, but she could guess what Aguri was about to say. “Aiming a gravity wave transmission at a black hole implies a receiving entity. That’s why you fired nanomachines toward Kali, isn’t it? To find that entity?”
Agnes’s hunch had been correct. “I was your age when I did that experiment. Maybe your examination of the existing data is the next logical step.”
“But
why didn’t you confirm it with another experiment? Maybe they wouldn’t let you then, but you could do it now.”
The question awakened painful memories for Agnes. “I have to think about others now,” she said at length. “About what’s best for AADD.”
Aguri clearly didn’t understand. Agnes felt she was looking into a mirror. At Aguri’s age, she hadn’t been able to grasp the concept of personal responsibility either.
“That incident has always been attributed to AI failure,” said Aguri. “But the gravity wave transmission the AI detected was identical to Atwood’s signal. At least, the format is the same.”
“There’s another interpretation. Maybe Atwood’s signals and the Ouroboros signal both come from regular, human-induced structural perturbations.”
“But Shantak II’s detectors are suspended in a magnetic field, isolated from the ship and from external vibrations. You know that as well as I do. We can rule out a false reading. The only other possibility, given the identical signal formats, is that the Ouroboros AI really was picking up a gravity wave transmission like the one we’re seeing now.”
“Then why haven’t there been any transmissions aimed at the AAD since then?” Dr. Agnes asked.
Aguri stared, baffled. Agnes was a scientist. Even now she must be convinced that Kali harbored an unknown life-form. Why look for objections to data that might point to the reality of an extraterrestrial civilization?
“Agnes, listen to me. We changed Kali’s orbit. If the Ouroboros signal was originally intended for Kali, the black hole isn’t in the right location to receive it anymore, because we moved it. These transmissions appear to be very tightly focused.”
“Appear to be, yes. But that’s just an assumption. Focus presupposes intention, and there may be no intention at all behind these signals. It’s all speculation. We have very little reliable data. How are you going to get around that?”
“There is a way—manned interstellar missions. If the signals beamed at our system are being transmitted to other stars in the galaxy, we should be able to verify that. And that calls for sending humans, not just probes!”
“Manned spacecraft have to be far more reliable than probes, you know.”
“I think it would be worth it,” Aguri said.
“Is that why you came to see me personally?”
“Is that a problem?”
“Talking to me personally isn’t going to move things forward. If you really think manned interstellar missions are necessary, submit a formal proposal. If you convince the steering committee, then in ten years your first spacecraft might be departing on its mission.”
“My spacecraft?”
“Of course. Once you propose it, it’s your baby.” Agnes felt a twinge of déjà vu. Eighteen years ago, when Agnes had described her idea for an experiment to fire nanomachines through Kali’s ergosphere, Catherine had said the same thing to her.
Eighteen years from now, Aguri would say these words to someone else. Who would it be?
2171
Port Shiva, Titania
Agnes hurried over to the console where Shi’en was standing. “What do you mean she’s in no condition to leave port? What’s going on?”
Shi’en returned her gaze calmly, as if she’d been expecting this reaction. “Titus Andronicus is a military spacecraft, and she’s not going anywhere right now.”
“I got that. I want to know why.”
“Because she’s in dock for a major refit.”
“What refit? No one told me.”
“I’m not surprised. This is a Guardian project. We’re upgrading her fire control systems. All of her weapons have to be dismounted. At this moment she’s useless as a warship.”
“How long will the refit take?”
“Agnes, could you calm down a little? A dismount/remount for a battery of laser ordinance and ultra-long-range pulse cannons can’t be hurried. It certainly won’t be finished in time to do anything about Caliban.”
“Can’t you send it out without weapons?” Agnes asked.
“Titus Andronicus was built to deal with armed incursions from Earth, not internal security problems. It’s going to take weeks to refit. Anyway, if the stalemate’s still unresolved by the time Andronicus is ready to leave dock, you’ll really have problems.”
“Damn it… Yes, you’re right, of course.” Agnes kicked the floor of the shop in irritation, launching herself upward fifty meters. She reversed her trajectory, pushing off from the underside of the next level to float back down in the microgravity; she landed on her feet in front of a holographic projection of a sharply tapered silver cylinder. The ship it represented was three and a half kilometers long, shaped like a huge tusk.
This was humanity’s first interstellar spacecraft, Caliban. The base of the cylinder was encircled by twenty-four chemical boosters. These boosters—burning first methane, then hydrogen—would accelerate the spacecraft to the optimum speed for ignition of its antimatter engines. They would also ensure that the ship was at a safe distance from Titania and its hundred million inhabitants before the ship’s antimatter engines began spewing huge amounts of radiation.
Titania was at aphelion, the best position for Caliban to begin its journey. The problem was simple: the ship was carrying 160,000 tons of stolen antimatter.
“What do you intend to do, Shi’en?”
“Nothing. Wait. See what Aguri does. The antimatter on that ship—and the radiation it will release if it fires its anti-m drive—has made hostages of Port Shiva and one hundred million people.”
“Is that why you don’t want to use Titus Andronicus, even for a demonstration?”
“I can’t. I wouldn’t even if I could. We don’t solve problems like this with force. Andronicus and her sisters were built as symbols of deterrence. Terrans understand such symbols. They were developed to project power, not to use it. Unless there’s no other option. You have to understand that.”
But Agnes already seemed to have abandoned the idea of trying to put a scare into Aguri. She absently poked a finger into the hologram in the vicinity of the crew quarters. “Has Aguri really commandeered the ship?”
“You’re a scientist, Agnes. You may not want to accept the situation, but I need you to open your eyes. She’s taken control of Caliban.”
Caliban had been constructed to investigate the source of the anomalous gravity waves, the existence of which had been confirmed by multiple unmanned probes. While a few scientists still insisted that the transmissions were a natural phenomenon, most believed the data proved the existence of an extraterrestrial civilization. Both camps agreed on the need to devote more resources to observation.
Furthermore, Shantak II had just completed observations, unprecedented in scale and detail, of the dwarf galaxy Eingana—observations that confirmed the presence of phase-modulated gravity waves. This added fuel to the arguments favoring stepped-up investigation. It also reinforced the confidence of the team working to develop manned interstellar spacecraft, since the main goal of such vessels was the search for extraterrestrial intelligence.
Initially Agnes had managed the program; later Aguri had taken over. Development had proceeded smoothly. Through close team collaboration, it had taken only seven years to complete the prototype spacecraft instead of the decade or more projected by the plan.
The original plan hadn’t included sending Caliban to the stars. Instead, the ship’s design and operating systems would be tested in visits to the Kuiper belt and the Oort cloud. Such distances were great enough for shakedown voyages, but not too great for high-speed rescue craft if problems were encountered.
Caliban’s operating trials were set to continue for five years. After that, construction would begin on additional spacecraft, and after another five years, a manned interstellar probe would depart for the stars every year. The first data was expected to reach the solar system around the year 2200.
Evidently Aguri hadn’t been willing to wait ten years for the first spacecraft to launch
. In theory, Caliban was fully capable of interstellar travel; however, because of the project plan it hadn’t been fueled to capacity with antimatter.
Aguri’s reaction to the cautious rollout plan was vehement. “We have the ship and all the fuel she needs. The only problem is our lack of will! The evidence is staring us in the face. An extraterrestrial civilization is sending out signals. What are we waiting for?”
But she had forgotten one reality: AADD encompassed a wide range of outlooks and values. Older steering committee members understood the importance of manned interstellar exploration, but they saw Earth as an unfriendly presence—the incidents on Shantak II had only served to confirm that—and were more concerned with husbanding resources for possible conflict with Earth.
The younger generation of AADD officers didn’t see Earth as a significant threat. For them, the search for nonhuman civilizations was far more important and any surplus resources should be funneled into those efforts. The generations talked past each other—and Dr. Agnes was with the older members. The last time they’d met, Aguri had listened impassively to Agnes’s arguments against plunging ahead without further preparation. Now Agnes sensed that her urgings had probably struck the younger woman as betrayal, though on the surface Aguri had seemed to accept them.
But Aguri had hacked into AADD’s Distribution Management System and arranged for stockpiled antimatter to be transferred to Caliban under false pretenses. She and a crew of like-minded confederates had been just hours from launching Caliban toward the source of the transmissions when the Guardians had discovered her intrusion. The entire interstellar exploration project had been frozen, Aguri’s crew summarily dissolved.
Why couldn’t she wait ten years? This was a mystery to Agnes, but with 160,000 tons of antimatter in orbit around Titania, it was a mystery of decidedly secondary importance.
Agnes had been staggered to learn of Aguri’s crime. When she discovered that Aguri had seized Caliban—and threatened to fire its antimatter engines if the Guardians attempted to board—she had been overwhelmed by a sense of helplessness.
The Ouroboros Wave Page 24
