"Yes, I can provide eight quantum storage units and eight readers."

Emwiller wasn't ready to let go. "Our I/O links are pretty fast. Can you transmit the basics of the theory and technology to us on how to build the reader?"

"Yes, I can do that. With the bandwidth I expect you to provide, it will take approximately three weeks to provide all the information on the reader, itself. It is not a simple device, and a wide variety of other technologies must be explained in detail before you can build it. Many of the design specifications are on the atomic level. Some even require customized nucleon lattices. There are components whose functional configuration demands the precise placement of considerable quantities of individual atoms. It is a large amount of data."

Hannegan said, "We shouldn't have expected it to be easy, but precisely placing umpteen trillion atoms? Yeah, that'll take us a while to figure out."

He thought for a minute. "Let me ask you this: Do you have compilations of physics, chemistry, and biological processes that could be transmitted separately and more quickly over our limited bandwidth?"

"Yes. If you wish to prioritize those among the goods you trade for. Other species have done so. When shorn of false trails, error, discussion, and philosophy, much of this galactic arm's research into those areas can be delivered in approximately six days, four hours, three minutes, and 7.4 seconds, if your technician's description of your I/O processes and bandwidth is correct. If you choose this trade, the trade system can establish a parallel I/O link."

Hannegan said to Stuyvesant, "The admiral'll have to sign off on using our trade points for that, but I think that's the way to go-get as much of basic science as we can, while we can, in the I/O stream. We can pass the science along to Earth as quickly as we get it. If the ship gets blown up on the way back, we're gonna lose both the readers and the QSUs, anyway. . . . Better to have the science, than a little bit of random tech about the QSU readers."

Stuyvesant nodded: "I agree. Let's get that started."

The jukebox spoke up, unprompted: "Your communications technician wishes to speak to you about placing a communications link on the surface of the station. He cannot reach you with your radio/video link."

"Why not?" Hannegan asked.

"Unregistered electromagnetic radiation is suppressed between rooms in the station. Not all the trade items stored here are neutrally receptive to electromagnetic radiation."

"I'll get it," Emwiller said. She walked toward the hallway where the tech had gone.

Crow said, "I'll come with you."

Sandy handed him the mini-Red that Fiorella had been using: "Take this. It's running."

When they were gone, Clover glanced at the other crew members, then asked, "Is there a God?"

Wurly: "Concepts of God are extremely varied but the consensus of the varied species put the probability of the existence of God at forty-two percent."

"Really?"

"No, not really. I was programmed to answer in this way. Concepts of God are so varied that no computation is possible."

Stuyvesant: "John, did you catch that? His maker had a sense of humor."

Clover nodded: "Yes. Wonderful."

Clover asked, "Your lack of information strikes us as a form of secrecy. Why so much secrecy?"

The answer-bot rippled mauve and puce for a second.

"This question is frequently asked, in various forms, by new arrivals. The purpose of depots like this one is to allow contact between alien species without direct contact. Early on, direct contacts were tried many times, by many different species, in many different ways. It almost always went badly. With few exceptions, alien species are too different from each other to allow constructive interaction. At best the efforts were extremely discomforting to one or both of the contactees. At worst, one or both found the other genuinely repugnant in some way.

"Contact invariably began with good intentions and no thoughts of hostility. Almost invariably those intentions failed. None of the failures were productive, and some of them were catastrophic. Eventually the surviving species still capable of interstellar travel devised this system of depots to safely provide some degree of cooperation and interaction.

"The depots provide two services. They are fuel production and storage facilities for antimatter-powered starships, and they are 'trading posts' of a sort. Arriving ships have automatic access to the antimatter storage vessels. In addition, they may offer trade goods, which are scored by a trade computer. They may take away items from the storeroom with similar scores, up to eight."

Clover was intrigued: "There is no medium of exchange? Just a scored swap?"

"That is correct. It is very difficult to measure the relative value of alien goods to other alien species. Our trade computer is highly sophisticated, but even so, there are continuing efforts to upgrade it."

Clover said to Stuyvesant, "Well, I'll be sheep-dipped. The advanced interstellar culture operates on a barter system. Never saw that one coming."

He turned back to Wurly: "You said with few exceptions there were problems. But there were exceptions? There were species that did get along well?"

"Yes. There are several pairings of cooperative species and even a sequence of similar species based on what Earth science would call convergent evolution. I have no information on those species."

Clover said, "About this trade system . . . the trade items seem fairly trivial in value compared to the cost of actually retrieving them. The ship that just departed was several cubic kilometers in size. Why are these ships wandering around the galaxy? Trade can't be the primary motive, can it?"

Wurly said, "No. Most ships that stop here are colony ships, on their way to colonize new planets. A certain percentage of technological societies severely damage their own planets before they become mature enough to understand the damage they are doing. In the past, a number of species have gone extinct before they achieved interstellar flight because of that damage, usually through runaway biological warfare or atomic warfare, with its consequent radiation poisoning. Those that do manage to survive despite badly damaged planetary ecosystems often look for a place to begin again to assure species survival. Planetary systems are quite common, although those that fit specific biological niches and that are not yet inhabited by advanced sentient creatures are not. Therefore, colony ships. Precise statistics are not available because of potential sampling error but it appears that between fifteen and twenty percent of advanced star-faring civilizations will sponsor at least one colony ship."

Stuyvesant asked, "Why would they stop here? It can't be to pick up antimatter: they would have done that at their home system and they'd already be traveling as fast as it's possible to travel with any given technology. . . ."

Wurly said, "No, the primary purpose for stopping is to restock supplies of consumables. Even with advanced recycling systems, some material is eventually lost and so stops are necessary. Water, for example-it would be possible to take along enough water to replace that lost on a multi-century flight, but that would add hugely to the mass that needs to be moved. The antimatter here is used simply to get them back up to traveling speed. The actual stop is made to restock consumable supplies harvested from the planetary rings."

Clover said to Stuyvesant, "Saturn's not just a recharge station. It's a convenience store."

Emwiller, Crow, and the comm tech came back, and Emwiller said, "We're gonna have to fab an interface to one of several possibilities suggested by the station, and the station will provide a constant-broadcast link back to the Nixon. We can't do it here. The most important thing we can get out of here will come over the I/O connection, so we need to head back."

Sandy asked the jukebox, "Wurly, could you direct us to the trade computer?"

"Yes, it is down the hallway number 2, opening to your right."

Sandy said to Emwiller, "We've got two guitars, a bass, and an amp with us. I think we should take the time to get them evaluated."

Clover said: "Stuyvesant and I have lots more questions, and Hannegan, too. . . . Every minute brings up amazing stuff. Give them time to talk to the trade computer."

Crow said, "I'd like to look around some more, anyway."

Emwiller nodded: "Okay, but if it's gonna take a while, if it's like a DMV or something, you gotta be willing to cut it off so we can head back."

The evaluation didn't take long. The trade computer was parked in a short dead-end hallway, and when they approached, it asked, in Wurly's voice, "Trade items for evaluation?"

"Yes."

"Please provide a simple description."

"Three musical instruments operated by vibrating strings which cause sound waves in gaseous atmospheres, and an electronic amplifier, powered by a battery."

"These are somewhat common instruments, but have some value, as well," the computer said. "Can you demonstrate their function?"

"Yes. It'll take a minute to plug in . . ."

They plugged in, and Martinez said, "We oughta go with our best number."

Crow: "'Yellow Dog Blues'?"

"That's what we got."

Sandy, "Okay, 'Yellow Dog Blues,' let's do it right: Everybody ready? Uh-one, anda-two, anda . . ."

"Yellow Dog Blues" lasted two minutes and nine seconds and when they finished, the computer said, "How many units of the instruments and the amplifiers can you deliver?"

"How many do you want?"

"Seventeen. For seventeen units, each unit consisting of three instruments and one amplifier, we will award you two-point-five points. Eight points is the maximum we may allow."

"Two-point-five? Shit, you're a tough audience. Okay, you got a deal," Sandy said.

Crow: "Seventeen units-is that in base 8, or base 10?"

The computer said, "Base 10. When communicating with you, all numbers are in base 10."

At the jukebox, Emwiller asked, "I think we understand the rules by which this depot operates, but what happens if someone breaks them? For example, what if a ship tries to take more than its share of goods or insists on approaching a depot when another ship is docked here?"

Wurly said, "The depots have some defenses. While you would find them overwhelmingly effective, most species that can build starships could overcome them. The network relies on disincentives. If a ship knowingly violates the rules of conduct, that information is propagated over the network to the security systems on all the depots. For some period of time, access to those depots is denied to other ships belonging to that species. The length of time depends upon the seriousness of the violation."

Emwiller persisted, "But what if some species ignored those denials and took what they wanted by force? What would prevent them from doing so?"

The answer-bot flashed silver, red, and lavender. "I do not know of any such occurrence. There's nothing in my historical records to indicate that that has ever happened, although those only go back 21,682 years. Also, I cannot find any information that would constitute a useful reason for this to happen. Essentially, it would require disabling a depot to overcome its defenses, rendering it useless for any future visits."

Emwiller started to ask another question, but Clover interrupted. "I think I get it. Destroying a depot to get what you want, when it gives stuff away freely, would be killing a goose that laid the golden eggs. You could, if you're shortsighted." He stopped, thought for a moment. "I wonder, can a species that embarks on multi-century voyages be shortsighted? Good question . . ." He looked off, lost in thought.

"John!" Emwiller snapped.

"Ah, yes. I was saying . . . you could do that, but then the sanctions would kick in, and your only options would be to cooperate or to continue to kill the geese. Mass goosicide eventually takes down the network, and then where are you for interstellar travel? Besides which, at sublight speeds, this would take millennia, maybe hundreds of millennia. How many species have policies that are stable-and homicidal-for that long?"

"The only reason that could make sense for doing this would be to force policy, to blackmail the trading system into doing what you want or risk further destruction. But there's no one making policy! The depot network just does what it does, following a set of preestablished rules. You can't threaten it, because it lacks volition. It'd be like trying to threaten, oh, Sandy's camera-'Give me what I want or I'll destroy all your fellow cameras, mwahahaha.' Yeah, that'd work." He laughed. It echoed deafeningly in the chamber.

Stuyvesant said, "So, basically, you're saying that the system is stable and robust because it's too simple and dumb to be broken?"

Clover nodded: "Yup. I think so. A primitive barter system, a really simple set of rules, and no system of flexible governance. I think you can 'game' it about as well as you can game a toaster."

Sandy, Crow, and Martinez emerged from the side hallway without instruments: "We got two and a half points," Sandy said. "It's something. Let's see what some of the commander's tea and Clover's booze"-Clover winced again-"will get us."

Fang-Castro poured two cups of tea and pushed one toward Crow. "Any change?"

Crow took a chair, shook his head. "No. The Chinese will be entering orbit tomorrow. Not only are they not talking to us, the Chinese government isn't saying anything useful to ours. We haven't seen any rendezvous craft splitting off, and it still looks like their ship'll be coming in close, inside the D Ring. It'll pass less than five thousand klicks above Saturn's atmosphere. It's coming in on a conventional high-inclination trajectory like we did, presumably to avoid ring particle impacts."

Fang-Castro took a sip of tea and said, "That's all by the book. It's how I would do it if I were commanding their ship. Come in steep and make your burn as close to Saturn as possible to get the most benefit from the delta-vee. Does that fit with your briefings?"

"Yes. Except my guys don't think they have enough reaction mass to achieve orbit. At least, not any kind of an orbit that would leave them in a position to resupply their tanks, let alone rendezvous with the aliens' depot. They'll be stuck, powerless, in orbit around Saturn. That's one case. The other is that they don't achieve Saturn orbit at all, in which case they've got a very long trip back to the inner solar system, and they're still powerless."

"Okay. What do we do about it?" She cradled her cup and looked at him patiently.

Crow sipped tea, said, "You gotta give me a list of your teas when we get back."

"It's a short list, but a good one. Of course, if Darlington has his way, it'll all be traded away. Enjoy it while you can."

"I will. Santeros and her group haven't made decisions yet, about the Chinese. Or, at least, not any she has communicated to me. I think it will depend upon the circumstances and whether the Chinese request our assistance. Then she'll weigh the options and tell us what actions to take. If any."

"It's coming down to what we talked about, David," she said. "If the Chinese government privately requests assistance as one government to another, that's for Santeros to work out. If the Celestial Odyssey directly issues a distress call or a request for aid and assistance, it's my decision, and it isn't even a hard one. We assist. To whatever extent is necessary to assure the safety of their crew, if not their ship."

"The President might order otherwise."

"The President doesn't get to decide. The Law of Space is clear on this point. When not in time of war, if a space vessel or establishment issues a distress call, any other vessels or establishments that can render assistance must do so, as long as it does not put them in danger. It's like maritime law but it's got much bigger teeth. If an oceangoing vessel is in bad trouble, people are likely to die. In space, it's a certainty. Failure to render assistance is classed as contributory homicide under international law," Fang-Castro said. "If I render assistance against the President's orders, she will have me court-martialed when we return to Earth. If I fail to render assistance in accordance with her orders, the International Court of Justice will try me for homicide and they will convict me, with a sentence of life in prison."

Crow said, "It is this president's policy not to allow U.S. military officers to be subject to trial by the International Court."

"That does not reassure me, David. My predecessor on the space station had to deal with the mess created the last time the U.S. flouted international space law, back in the early fifties. Look it up. 'U.S. Interops Space Litter Fine' will get you there. That president stood tough, until he discovered how powerful passive-aggressive disapproval can be in space. The U.S. cannot afford to be a pariah among the spacefaring players. Santeros will turn me over, when it sinks in just how much protecting me will cost the U.S."

"You're sort of skipping over an important point, Naomi," Crow said. "We're required to render assistance if it doesn't put us in danger. But what if it does? Who decides what constitutes danger? What happens if Santeros and her intel people decide that taking Chinese troops into an unarmed vessel is automatically dangerous, and they communicate that to you?"

Fang-Castro looked up at the ceiling, thought about it, then looked back at Crow and smiled. "You know what? If they did that, and I ordered a rescue anyway, then it would all come down to what the Chinese did. If we rescued them, and that was it-we simply hauled them back to Earth on friendly terms-then Santeros wouldn't do anything. I might not get another star, but that would be the end of it. On the other hand, if the Chinese did try to take our ship, and I survived, then I'd probably be court-martialed and convicted."

"Yes." Crow put his fingertips together. "It ain't pretty. So what are we going to do?"

"Well, I think you should get word of this conversation back to Santeros, so we don't wind up putting ourselves in a mutually untenable situation. Convince her to leave the decision to me, and I'll take full responsibility for whatever happens. She can find reasons to do that-for example, our comm lag is now so bad that she would be unable to provide me with minute-by-minute orders, and blah-blah-blah. Her PR people can handle it."

"I don't know if they'll go for that, but I can try," Crow said. "They may try to download about a thousand different scenarios on us, everything they can think of, with specific orders for each one."

"Tell them not to do that. If I tried to follow their scenarios, something inevitably would get screwed up, and they'd get blamed," Fang-Castro said. "No. You tell them if something goes wrong, I'll take the blame."

"I'm not sure they're so worried about who to blame-it'd be you, no matter what happens-as they are genuinely worried about what would happen if the Chinese got all this tech, and we didn't. If they grabbed our ship, and, you know, took it and kept it."

"I worry about that, too. Which brings me to something else I need from you. I need you to analyze the security situation should we be required to take an indeterminate number of crew members from the Celestial Odyssey on board."

"We're working on that."

"David, I've never asked you this, but it's time to put a few more cards on the table. How many trained military personnel do we have on board the Nixon?" She held up a hand to stop him before he began to answer. "In total. Not just the official complement, but including the ones you had placed undercover among the regular crew members. Like Sandy Darlington. No, you don't have to give me names. Not yet. I just want the head count."

Crow didn't hesitate. "We have fifteen. Including the official eight, you, and First Officer Francisco."

"Mmm," Fang-Castro said. "I'd hoped for a few more. What's the latest guess on how large the Chinese crew is?"

Crow shook his head. "No change there. It can't be fewer than twenty-five. We can't imagine any way, technically, to run that ship with fewer people. Fifty might be a plausible guess. But it could be larger than our complement, maybe over a hundred."

"David, that really doesn't help at all," Fang-Castro said. "You better start grinding out your own scenarios. And we better hope that the Chinese have their situation under control, and this doesn't come up."

Crow said, "We'll get those memory things from Wurly, those quantum devices, the next time over. Supposedly, that's everything they've got-science, tech, everything. We could simply say that we didn't want to get in an untenable position here, given the lack of cooperation from the Chinese government . . . and then leave."

"What would Santeros say to that?"

"Listen, what Santeros wants is every bit of information we can squeeze out of the alien station, and she doesn't want the Chinese to get any of it," Crow said. "She knows that's probably not possible, but that's the baseline of what she wants."

"I don't see any way that could happen."