Or suppose opening the wormhole now, in a hurried, unconsidered rush, would bring some other danger home to the Solar System—or wreck the Ring of Charon beyond repair, and thus destroy the last hope of some future contact with the Earth?
Or suppose that this was it, the last best chance to use the Ring? Suppose this wormhole activity ceased, and the Charonians cut the link or destroyed it, and the Ring of Charon never, ever, detected another usable tuning frequency?
And she had to decide.
She was nearly at the last of the gibberish interpretations the pattern-matchers kept offering up, when something that seemed orderly scrolled past the screen, almost too fast for her to see it.
She frowned, and moved the scrollbar back. Forty zeroes and ones run together, repeated three times. The pattern matcher had broken the string out in various ways. Two twenty-digit numbers, four ten-digit numbers, eight five-digit binary numbers and so on.
Five digits… Not a very useful length. The largest number you could express in five binary digits was 11111, or 31. So why did the computer bother to break it out that way?
And then it hit her. Because of 26. Because 26 was smaller than 31, and you only needed 26 numbers to express a certain rather useful symbol set…She started working in her head—but no, this was no time to drop a digit and get confused. She punched a few mindlessly simple commands into the pattern matcher and the answer popped up on the screen.
And all of a sudden, her decision was much simpler.
Dianne sat at the captain’s chair in the briefing room as Gerald MacDougal stood by the wall screen, using the wall controls to stop the playback again.
He locked onto one frame of the images sent back by NaPurHab, a slightly blurry picture of a small grey world lit in half-phase, hanging over a cracked and pitted red-black surface that filled the background. What looked to be a SCORE was visible toward the right edge of the frame. “Once they entered the wormhole, we only got about ten seconds of video and other data before we lost the signal,” he said. “Earth didn’t do any better. Nowhere near as much as we’d hoped for, and that’s the single best image.”
“Why so little data?” Dianne asked. “Five years ago, when the Saint Anthony went through the wormhole from the Solar System to the Multisystem, we got hours and hours of data.”
“They had time to set things up for a proper line-of-sight relay straight through the wormhole,” Gerald said. “NaPurHab didn’t manage to launch a relay, or else the relay failed immediately. Without a relay, we had to have direct line-of-sight with NaPurHab to get a signal—and the moment the aft end of the hab entered the wormhole, the signal was cut off.”
“How so?”
“Think of the wormhole as a long thin tunnel. If the Terra Nova had been lined up with one end of it, we could have seen all the way down it, and we would have picked up NaPurHab’s signal as the hab beamed it out of the tunnel. But we’re well off to one side of the wormhole—and the moment they entered it, the tunnel wall cut off the radio link.”
“So the lack of data doesn’t mean they were killed instantly, or anything like that?” Dianne asked.
“No. All the telemetry was more or less normal up until the moment of cut-off. We were getting a lot of indications of structural stress, but that was to be expected, and it was well within tolerance.”
“So this is the best we have,” Dianne said, getting up to look at the video frame. She stared at it for a long time, searching it, trying to pull meaning out it—and succeeding. This told her things. Including things to do.
“So there’s a planet in front of a Sphere like ours. One clear frame of video can’t tell us much past that,” Gerald said, after the silence had dragged on for a bit.
“The hell it can’t,” Dianne said. “There are lots of dogs not barking in here.”
“I beg your pardon?”
“Read your Sherlock Holmes,” she said. “When a dog that always barks stays silent, that’s a clue too.”
“Ah. Okay. So what don’t you see here?”
“Shadows,” Dianne said. “No multiple shadows, no illumination at all in the darkened hemisphere of that little world.”
“Meaning?”
“Only one light source. If that red-black is the surface of another Sphere like ours, then it should have two or three dozen Captive Suns orbiting it, the way ours does. Any planet there would have seven or eight captive stars shining on it at any given moment. And yet there is only one light source here. That tells me this Sphere has lost nearly all of its captives.”
“Okay, I guess. What else?”
“The surface of the Sphere. It’s banged up as hell. Lots of impacts on it. It’s not protecting itself against debris.” Dianne stabbed a finger down on one of the larger features. “And that looks like a wide-angle crack going all the way through the surface of the Sphere. It’s much darker than the bottom of the other cracks and craters.”
She shifted her finger to point out a pair of straight lines crossing at right angles, almost out of the frame toward the bottom. “And that looks a hell of a lot like one of the ‘latitude’ lines intersecting a line of ‘longitude’ on our Sphere, seen from damned close-up.”
Gerald stared at the image himself, stepped back from the screen for a minute to get a better look. “You’re right,” he said. “I was just seeing that as two long straight cracks, but you’re right. Hey wait a second.”
Gerald thought for a minute, then turned to the table and grabbed a datapack. “We’ve got the optical data on the cameras NaPurHub was using,” he said. “Let’s see. Factor in the focal length of the lens, assume those lines are the same width as the ones on our Sphere, and that gives us a scale. Get the apparent width of the lines and we’ll have a range to the Sphere in the picture.” He measured the line width ami punched the numbers into the datapack. He looked at the answer, then ran the problem again. “I don’t believe it,” he said. “It couldn’t be that close.”
“How close?” Dianne asked.
“Twenty-two million kilometers,” Gerald said. “NaPurHab came out twenty-two million kilometers from the surface of a Charonian Sphere.”
“A dead Charonian Sphere,” Dianne said. “A Sphere that can’t hold onto its stars, that can’t prevent impacts on its surface. And to hell with being close to the Sphere. Remember what Sturgis and Colette figured out, that the Lone World here, in our Multisystem, was Charon Central, the brains for the whole operation.”
She stabbed her finger down on the video image again. “That is the Lone World, Charon Central for the system NaPurHab is in. It is orbiting the Sphere directly. It is the place from which the Charonians controlled this system. Maybe it’s the Last World in that system, too, the only one left.
Gerald looked at his captain with something between fear and excitement in his eyes. “It makes sense,” he said. “I think you’re right.” He looked at the image again, and worked it all through, nodding to himself. “Yes,” he said. “It’s got to be.”
“So,” Dianne said, “There we have it.” Suddenly she knew what to do. “So now what?” she asked.