“Seems like Lenny’s had a problem with the Base one time before, when he saw a space-dog out on the antenna after he’d been a while in Gippo’s Bar. This time, nobody will give him half an ear. He has to head back to work, and by the time he hits Tycho again he don’t have any idea where that pod’s heading to. Maybe down to Earth, maybe off into the Sun.
“So there you got it, friends. What do you think? Do we have the Little People, moved out here mebbe now Earth’s not so friendly as it used to be? Or do you think there might be an engineer who’s firin’ skew on one or two jets? One thing’s for sure. We won’t know which, ’less one of you can take off after ole Lenny’s rock and check it for yourself.”
Anson leaned across and flipped a switch. “There you have it, Rob. That’s the whole thing, except for Tinman Petey’s sign-off. And that’s the same every time.”
“You talked to Pascal?”
“Sure. Tinman Petey too. I couldn’t get much more than what you heard from either of them. Lenny Pascal’s physical description was a little more complete, but he couldn’t tell me any more about how the pod first appeared or where it was heading.” Anson picked up a sheet from the desk in front of him. “You ought to photo-record this, but I can give you the main points in a couple of sentences. Body mass for the Goblins, as near as Pascal could judge, would be about five kilos. He thought their bone structure was pretty normal, though it was hard to tell because they were so broken up. The air in the pod was breathable, so they didn’t die of asphyxiation like the other Goblins we’ve encountered. Pascal says that their skin color was odd, but it was more like bruises, not cyanosis.”
“Too much acceleration?” Rob interrupted. “That’s what it sounds like. Did Pascal check the drive log?”
“That’s the odd part. He had the same thought as you did, and he felt they must have been exposed to more than thirty gees. He looked at the drive log in the pod and all it had been used for was small control maneuvers. Nothing big. In fact, Pascal said that he didn’t think a Mischener can give much thrust, even at top power.”
“He’s quite right.” Rob rubbed thoughtfully at his forehead. “I’d forgotten that it was a Mischener Drive. They’re controlled to half a gee or less. You could never modify one to get more than a couple of gees out of it — the whole thing would blow up.”
“I couldn’t modify any drive to do anything, but I know what you mean. I checked out that information on the Mischener Drive myself. I’ll get to that in a minute. Here’s something else for you. Atlantis is just about out in the Belt now, but I’ve been tracking its position as it moved. Take a look at this.”
Howard Anson held another sheet up to the camera. “Forty-five days old. A tracking station near the inner edge of the Belt recorded an unauthorized launch of a life-support pod from a point very close to Atlantis. Nobody sent out a Mayday, so the pod didn’t get tracked by Search and Rescue. All that happened was a violations report to Central Records. See how that would fit with what Pascal said about the pod’s log? The pod computer shared reference readings that say it started out in the Belt, thirty days before it drifted past the antenna farm. The time would fit perfectly. If the Goblins had started out from Atlantis in that pod, thirty days before Pascal sighted it, they’d have been just right to match that unauthorized launch. It would all be consistent, except” — he shrugged, a bewildered expression on his tanned face — “I don’t see how the Mischener Drive could do it.”
“It couldn’t.” Rob was shaking his head firmly. “Your argument won’t fly, Howard. I’ll do the detailed calculations for you if you like, but I already know the answer. There is no way you could fly from out near the Belt, where Atlantis was a month and a half ago, and get to the Moon on a Mischener Drive in thirty days. The orbit geometry is wrong. Anyway, the Mischeners don’t have the capacity for a continuous impulse trajectory, even at a fraction of a gee. They were designed for free-flight Hohmann transfer orbits, with a little bit of thrust at the beginning and a little bit more at the end.”
“So you’re saying the Goblins would have to have come in some other ship?”
“Must have, if they were going to get to the Moon in thirty days. If you want to do a fast transit from the Belt to the Earth-Moon system, you have two ways to go. You can ride a continuous-impulse ship, like the best medical vessels — and you’d still be limited to three gees, unless you could prove to the USF controllers that you had a real emergency on your hands. Did you know that the flight computers on every ship and every pod are sealed, and they keep a log of every time that the drives go on and off? I don’t know of any way to trick them. And you’d somehow have to fake the reaction mass you used, as well. I don’t think that’s feasible. The only other way you can get a really fast transit is to use a monster short-duration acceleration in place of a small continuous thrust. You’d do it twice, once at the beginning of the flight and again at the end. That would speed it up a lot at the beginning. You’d fly in fast, then slow down fast when you were close to Earth. People have talked about ships with that much acceleration for years, but nobody has ever built one. Not even for medical ships.”
“All right.” Howard Anson held up a protesting hand. “I’ll believe you, no need for the lecture. Ask you a simple question and you throw a book at me. So the Mischener Drive won’t do it, and the other drives can’t do it secretly. Doesn’t it seem too much of a coincidence, though, to have the Goblins arrive here with just the right timing for a pod launch from Atlantis? Aren’t you convinced that the Goblins live on Atlantis?”
“You know I am.”
“So if you won’t take my explanation, what’s yours?”
“I don’t have one.” Rob’s irritation was clear in his expression. “I’m with you, the Goblins started out from Atlantis. I believe there are some on Atlantis right now. But we can’t use magic to get them here. There’s some rational explanation to what Lenny Pascal saw and to what your Information Service dug up. I just can’t see it yet.”
Anson leaned forward to the camera. “You know I’m not a scientist, but I’ve got one other idea you haven’t mentioned. What about gravitational swing-by? The way I’ve heard about it, you can put a ship past a big mass, and if the positions are right you can pick up speed doing it. They used to use it to get ships past Jupiter and Saturn to the Outer System, when they didn’t have reaction mass available. Wouldn’t that be the way to speed up a passage in to Earth?”
“Yes — but no.” Rob saw Anson’s frustration. “Don’t blow yet, Howard. I’m giving you a serious answer, and I know you want to sort this thing out as much as I do. You are right in a way. Gravitational swing-bys are a good method of picking up free momentum, if you happen to be going past a big mass. But when I say a big mass, I mean a big mass. There’s nothing between here and Atlantis that could possibly do it.”
“You mean nothing that we know about. But what about the possibility of a black hole? That could do it. It would be very small, and we couldn’t see it. And Morton says that the Halo—”
He stopped. Rob was shaking his head again.
“Sorry to spoil your idea, Howard, but if there were a decent-sized black hole — one with significant mass — anywhere in the System, we’d have found it long ago. Its gravitational effects would perturb all the other bodies. Same applies to an unknown planet. There just can’t be an undiscovered mass in the Inner System. Not one big enough to have an appreciable gravitational field.” He shook his head. “Sorry, Howard, but we won’t find an explanation so easily. Anyway, your idea wouldn’t fit with what Pascal said about the way that the Goblins died.”