“You’re in luck,” Halsey said. “Looks like only three vessels fit into the cone, given the rotation of the planet and the logged positions just before the time of the incident.”

Runstom was scribbling notes furiously, knowing he would need all this information as evidence if he were going to convince his superiors that something fishy was going on with this case. “Okay. What are the three ships?”

Halsey punched up the cross-references of the positions and the ship data. “Let’s see. We’ve got a mail drone. An asteroid mining vessel. And … a cruise ship.”

“Okay, we’re looking for someone with a beam-based transmitter,” Runstom said, thinking out loud. “It’d have to be mounted to the outside of a ship, unless there were another place it could be stored, where it might have a way to send a transmission out of a port or something.”

“Stan, you ever think about what it’s like on one of those cruise ships? Now that’s some serious slacking.”

“George, come on.”

“Okay, sheesh.” Halsey leaned back to stare at the ceiling and scratch through the curls of his hair. “The mail drone seems a little far-fetched. Those things are too small to mount anything on, and they have zero cargo space. Unless you yank out the mail memory modules.”

“Yeah, well – that’d give you about half a meter square,” Runstom said. “And even then, there’s no passenger room in a mail drone. They just aren’t outfitted for people. No life support or anything. So it’d have to be all pre-programmed.”

“Or controlled remotely. But then, what would be the point?”

“Not to mention, the delivery companies keep track of those drones pretty closely.”

“Yeah, okay. So no room on the mail drone, unless it’s tampered with, which is highly unlikely, and then it’s questionable if you would even have enough room for a transmitter.” Halsey made a mark on the report. “So the mining vessel. According to the data, it’s a standard Galacaroid Maximiner. Crew of eight. Four front-mounted mining lasers, one front-mounted explosives launcher, and one small top-mounted defense turret with an EMP gun in it. Plenty of cargo space, of course, but inaccessible to the crew when in space. A handful of pusherbots do all the heavy lifting in the cargo bay during mining operations.”

“Hmm. Which one is that in the model?” Runstom asked.

“This one here. Farthest out.”

“So it’d need a pretty strong transmitter.”

“Yep.” Halsey punched up some quick calculations. “About 78 megasparks to send a signal that distance and maintain integrity. Plus, this one was only in the cone for a couple of hours, about five days before the incident.”

“So it’s possible,” Runstom said, pausing thoughtfully. “Someone would have to either mount a large transmitter in the cargo bay or yank out the mining lasers and make room for it on the front. Do we have log data of that ship in the system for any time after that?”

“Of course.” Halsey fiddled around for a few minutes, importing some of the traffic log data into the model. “Okay, here we go,” he said eventually and slapped a button on his console.

The model began to scroll forward in time. The little dot representing the mining vessel bounced around the asteroid field for a few minutes. Halsey yawned. Suddenly the dot zipped away from the asteroid ring and over to one of the outer planets.

“Where’d it go?” Runstom said.

“Uh. Let’s see. It went to one of the moons around Barnard-5. There’s some kind of refinery based there.”

“So it mined asteroids for a couple of hours and then went to a refinery,” Runstom said.

Halsey turned around and faced him. “Seems like a perfectly natural thing for a mining vessel to do, doesn’t it?”

“Yeah, I suppose so,” was Runstom’s answer. He wanted to say that just because someone was acting naturally, that didn’t mean they were innocent, but he kept that thought to himself. “Let’s move on to the last one.”

“Sure. Royal Starways Interplanetary Cruise Delight Superliner #5. Crew of 348. Not just ship operations personnel, of course, but including wait staff, maids, pool cleaners, porters, baggage handlers, masseurs, personal trainers, personal entertainers, day care—”

“Right, right, what else?”

“Mmmmmm. I’ll skip the weapons detail. Basically, this thing has a slow route that starts at Barnard-3, moves in close to Barnard-1, where it orbits for a short time. Then it goes to Barnard-2, orbits there for a bit. Then on to B-4, where it docks at the sub-orbital platform for a very short amount of time before continuing on. After that it orbits B-5, then orbits B-7, then comes back to orbit B-6, then spends some time near the asteroid belt, then it makes a slow cruise back down to B-3.”

“Those things take a couple years to do their whole route, don’t they?”

“Yep.” Halsey punched up some other data. “About nine years in total. A slow tour of the whole system, hanging about in orbit around the uninhabitable planets, stopping at a moon here and there. The full planetary experience for folks with too much money and even more free time. Of course, some people only go part way. It’s only the richest B-threers that can afford the full cruise.”

Runstom huffed. “Anyway – there are only like eight or nine or ten of these superliners, right? Just doing their slow loops of the system?”

“Yeah, something like that. So you can catch one at least once a year. Ours is number five of the pack.” Halsey went back to the holo-screen. “She’s this big dot here, in between the orbits lines of B-3 and B-4. I’ll load up her path data. I’ll start a couple weeks back in the log since she’s so slow.”

The dot jumped back a few inches on screen, which was probably a few million kilometers in real space. Halsey hit a few buttons, and it started to crawl forward. The cruise ship was traveling much slower that the miner had been, so he tweaked the speed of the model to get it moving. Barnard-4 has a long rotational period, taking about two Earth weeks to make a full spin. The model was moving at higher speed now, and the cone of contact sticking out of the planet swept around with the slow rotation. Eventually, the cruise ship got close enough to intersect with the cone as it crawled through space. A couple of days’ worth of real time ticked by as they watched the ship stay within the cone. The date of the incident came and went before the vessel’s path took it outside the cone’s coverage and it abruptly stopped.

“Two days ago – that’s the end of the logs I got. After this, she’ll be lining up to parallel B-3’s orbit and in a couple months’ time, she’ll match up to B-3 and hold position while shuttles unload and reload from the planet.” Halsey turned away from the model and stared blankly into the darkness. “Well shit,” he muttered after a moment of thought. “The cruise ship definitely sits in the cone for a few days.”

Runstom closed his eyes. “Okay. Assuming that someone hit the LifSup receiver at sub-dome Gretel, block 23-D with a signal from space. What we now know is that the only eligible spacecraft for the job are a mining vessel and a cruise ship.”

“Right. But if spaceships could be suspects, both of these have pretty good alibis.”

“Yeah, no kidding.” Runstom started writing in his notebook. “If it’s the mining craft, they’ve deliberately run a route that would appear normal. Covering their tracks. They would have planted the malicious code five days before it was triggered to take effect.”

“So five days it lay dormant in memory somewhere,” Halsey said. “Risking detection or possibly being wiped out with a system reset.”

Runstom nodded, and went on, keeping his momentum. “They were pretty far out, so they would have to have a large transmitter. Even if it weren’t mounted on the front, it would be obvious sitting there in the cargo bay. In fact, they might have to have the pusherbots move it into position. All eight of the crew members on board would have to be in on the whole plan.”