Prax nodded, as if by doing it he could will them to follow his chain of reasoning. Holden shook his head, paused, and then nodded.
“The bomb,” he said.
“The bomb,” Prax agreed. “Even when they didn’t know that the second thing was going to get loose, they’d outfitted it with a powerful incendiary explosive device.”
“Ah!” Alex said. “I get it! You figure they knew it was going to go off the rails eventually, so they wired it to blow if it got out of hand.”
In the depths of space, a construction welder streaked across the hull of the half-built ship, the light of its flare casting a sudden, sharp light across the pilot’s eager face.
“Yes,” Prax said. “But it could be also be an ancillary weapon, or a payload that the thing was supposed to deliver. I think it’s a fail-safe. It probably is, but it could be any number of other things.”
“Okay, but it left it behind,” Alex said.
“Given time, it ejected the bomb,” Prax said. “You see? It chose to reconfigure itself to remove the payload. It didn’t place it to destroy the Roci, even though it could have. It didn’t deliver it to a preset target. It just decided to pop it loose.”
“And it knew to do that—”
“It’s smart enough to recognize threat,” Prax said. “I don’t know the mechanism yet. It could be cognitive or networked or some kind of modified immune response.”
“Okay, Prax. So if the protomolecule can eventually get out of whatever constraints they’re putting on it and go rogue, where does that get us?” Naomi asked.
Square one, Prax thought, and launched in on the information he’d intended to give them in the first place.
“It means that wherever the main lab is—the place they didn’t release one of those things on—it has to be close enough to Ganymede to get it there before it slipped its leash. I don’t know how long that is, and I’m betting they don’t either. So closer is better.”
“A Jovian moon or a secret station,” Holden said.
“You can’t have a secret station in the Jovian system,” Alex said. “There’s too much traffic. Someone’d see something. Shit, it’s where most of the extrasolar astronomy was going on until we got out to Uranus. Put something close, the observatories are gonna get pissed because it’s stinking up their pictures, right?”
Naomi tapped her fingers against the tabletop, the sound like the ticking of condensate falling inside sheet metal vents.
“Well, the obvious choice is Europa,” she said.
“It’s Io,” Prax said, impatience slipping into his voice. “I used some of the money to get a tariff search on the kinds of arylamines and nitroarenes that you use for mutagentic research.” He paused. “It’s all right that I did that, isn’t it? Spent the money?”
“That’s what it’s there for,” Holden said.
“Okay, so mutagens that only start functioning after you activate them are very tightly controlled, since you can use them for bioweapons research, but if you’re trying to work with that kind of biological cascade and constraint systems, you’d need them. Most of the supplies went to Ganymede, but there was a steady stream to Europa too. And when I looked at that, I couldn’t find a final receiver listed. Because they shipped back out of Europa about two hours after they landed.”
“Bound for Io,” Holden said.
“It didn’t list a location, but the shipping containers for them have to follow Earth and Mars safety specifications. Very expensive. And the shipping containers for the Europa shipment were returned to the manufacturer for credit on a transport bound from Io.”
Prax took a breath. It had been like pulling teeth, but he was pretty sure he’d made all the points he needed to for the evidence to be, if not conclusive, at least powerfully suggestive.
“So,” Amos said, drawing the word out to almost three syllables. “The bad guys are probably on Io?”
“Yes,” Prax said.
“Well shit, Doc. Coulda just said so.”
The thrust gravity was a full g but without the subtle Coriolis of Tycho Station. Prax sat in his bunk, bent over his hand terminal. There had been times on the journey to Tycho Station when being half starved and sick at heart were the only things that distracted him. Nothing physical had changed. The walls were still narrow and close. The air recycler still clicked and hummed. Only now, rather than feeling isolated, Prax felt he was in the center of a vast network of people, all bent toward the same end that he was.
MR. MENG, I SAW THE REPORT ON YOU AND MY HEART AND PRAYERS ARE WITH YOU. I’M SORRY I CAN’T SEND MONEY BECAUSE I’M ON BASIC, BUT I HAVE INCLUDED THE REPORT IN MY CHURCH NEWSLETTER. I HOPE YOU CAN FIND YOUR DAUGHTER SAFE AND HEALTHY.
Prax had composed a form letter for responding to all the general well-wishers, and he’d considered trying to find a filter that could identify those messages and reply automatically with the canned response. He held off because he wasn’t sure how well he could define the conditions set, and he didn’t want anyone to feel that their sentiments were being taken for granted. And after all, he had no duties on the Rocinante.
I’M WRITING YOU BECAUSE I MAY HAVE INFORMATION THAT WILL HELP WITH THE QUEST TO RECLAIM YOUR DAUGHTER. SINCE I WAS VERY YOUNG, I HAVE HAD POWERFUL PREMONITIONS IN MY DREAMS, AND THREE DAYS BEFORE I SAW JAMES HOLDEN’S ARTICLE ABOUT YOU AND YOUR DAUGHTER, I SAW HER IN A DREAM. SHE WAS ON LUNA IN A VERY SMALL PLACE WITHOUT LIGHT, AND SHE WAS SCARED. I TRIED TO COMFORT HER, BUT I FEEL SURE NOW THAT YOU ARE MEANT TO FIND HER ON LUNA OR IN A NEARBY ORBIT.
Prax didn’t respond to everything, of course.
The journey to Io wouldn’t take much more time than the one to Tycho had. Probably less, since they were unlikely to have the chaos of a stowaway protomolecule construct blowing out the cargo bay this time. If Prax thought about it too long, it made his palm itch. He knew where she was—or where she had been. Every hour was bringing him closer, and every message flowing into his charitable account gave him a little more power. Someone else who might know where Carlos Merrian was and what he was doing.
There were a few he’d set up conversations with, mostly video conversations sent back and forth. He’d spoken with a security broker based out of Ceres Station, who’d run some of his tariff searches and seemed like a genuinely nice man. He’d exchanged a few video recordings with a grief counselor on Mars before he started to get an uncomfortable feeling that she was hitting on him. An entire school of children—at least a hundred of them—had sent him a recording of them singing a song in mixed Spanish and French in honor of Mei and her return.
Intellectually, he knew that nothing had changed. The chances were still very good that Mei was dead, or at least that he would never see her again. But to have so many people—and in such a steady stream—telling him that it would be all right, that they hoped it would be all right, that they were pulling for him made despair less possible. It was probably something like group reinforcement effect. It was something common to some species of crop plant: An ill or suffering plant could be moved into a community of well members of the species and, through proximity, improve, even if soil and water were supplied separately. Yes, it was chemically mediated, but humans were social animals, and a woman smiling up from the screen, her eyes seeming to look deeply into your own, and saying what you wanted to believe was almost impossible to wholly disbelieve.