Boundary b-1

by Eric Flint

  "Burn to match orbits set for 1435:04. Deployment of ISM units will follow at approximately 1600 to allow for verification of burn success and deployment readiness."

  Time for him to take a break. Once the deployment happened he was going to actually have something to do for a change. He couldn't control the Faeries-the Independent Sensor Modules or ISMs in official parlance-in detail at a distance, of course. The speed-oflight lag meant that even at closest approach to Mars, he'd still have a round-trip delay measurable in minutes; at maximum distance it was close on half an hour. But he could give them a lot of general guidance, especially if he thought ahead carefully.

  He'd been doing a lot of mission profile planning for the past several weeks, including disaster contingency plans. Hopefully that part of his work would turn out to be wasted. A.J. intended to work out all the systems to their fullest extent, and that meant he would actually have to take a few risks-something he couldn't do if he lost any of the Faeries on deployment. He'd need them all intact before he could take chances.

  A drive and a late lunch sounded like a good idea. If he were back at Ares he could've grabbed Joe to go with him, but things weren't quite that casual here at NASA. Most people were busy right now, anyway. He headed to the parking lot and was soon driving down the commercial strip in the nearby town, looking for something appropriate.

  Not fast food, thanks very much, A.J. said to himself as the neon and brighter lights of said establishments tried to beckon to him. I need real food to keep me going tonight. Well, real food and then a sack of doughnuts and coffee. Ah, there we go, a steakhouse!

  Getting a table in midafternoon was easy; the place was almost empty. He checked the menu, ordered, and then sat there in the quiet, waiting.

  A.J. hated eating alone. After chewing on the problem for a moment, he pulled out his phone and dialed a still-familiar number.

  The tanned face that materialized in his VRD vision was streaked with sweat and dirt, and the golden hair pulled back but escaping in tangled disarray.

  Damn, but she looks good.

  "What's up, Doc?"

  "A.J.!" Helen Sutter's smile was brilliant against her honey-dark tan. Then she frowned in mock annoyance. "And will you stop greeting me like Bugs Bunny?"

  "Better, ah say, girl, better than Foghorn Leghorn!" A.J. retorted in his best drawling bellow.

  That got a laugh. "True enough. Well, as you can see, I'm in the middle of a dig right now. What's up with you, almost-Doc?"

  "I'm in a restaurant completely alone, and wanted to see if I could at least have virtual company. I thought you might be able to indulge me. Time for a call?"

  "Oh, I suppose I could take a little break. But if you're in an even vaguely respectable place, I sure hope you're not using a projector. I'll bring down the tone of the place. Badly."

  "Purely for my eyes only. But even just like you are, you'd bring the tone of any place way up."

  "That's why I put up with your antics-you know how to flatter a woman."

  "Flattery? Never. I just tell the pure and honest truth. The secret is knowing that women like you never believe that they really are gorgeous."

  Helen studied him for a moment, her head cocked a little. The expression on her face was a bit disconcerting to A.J. A sort of distant amusement combined with… something else, that he wasn't sure about.

  He was reminded, not for the first time, that badinage with a very intelligent woman twelve years older than he was could be a chancy proposition.

  Abruptly, Helen changed the subject. "So what's up with your work now?"

  "The Faeries get to fly in a few hours. Pirate just succeeded in the aerobraking maneuver to get her into a closely matching orbit to Phobos."

  "That's great, A.J.! I'll bet you're excited."

  "Yeah. Yeah, actually, I am."

  Helen's head was still cocked, subtly inviting an elaboration.

  He was rather surprised to find he meant it. After being taken off the flight crew, he'd spent weeks working simply because he hadn't had much else to do and he didn't know how to just slack off. He was out of practice, having been working like a demon since he was fifteen. "You know, I really am!"

  Helen's smile flashed again, this one warmer and with a touch of sympathy. "I'm glad. I could tell you weren't doing well at all for a while there, even though we only talk occasionally. Your e-mails just didn't have the usual A.J. edge."

  "You mean bad puns and stupid humor."

  "That too," she said, chuckling. "But really, you have a voice all your own. And as annoying as you can sometimes be, it's a signature that comes across even in a typed note. When I don't see something that says 'look, I've got something really cool to tell you' in the note, and instead get something that just reads like a thank-you note, I know something's wrong."

  "Well, have no fear, Milady Bonedigger. A.J. the Great, Imperator of Imaging, Sovereign of Sensors, Dictator of Detection, has returned!"

  Plates rattled. "And my lunch has arrived. I would share some of it, but somehow I don't think it'll work out."

  She looked wistfully at the table. "You are a cruel man, to call a woman who's working here in a hot desert and then taunt her with real food and drink when all she has"-she held up a small wrapped object-"is a granola bar and a canteen of warm water."

  "True, true. But it's an artistic kind of cruelty. I'll make it up to you, whenever you're back from digging. You name the place, I'll pay the check. Joe and Jackie could even join us, if you time it right."

  "I'd love to see them again. I know they've been busy in their training, though."

  "Don't worry about it. They can get enough time off to drop in and see an old friend, I guarantee you." A.J. started in on the salad. "If this really bothers you, I can cut off. I mostly needed company while I was waiting with nothing much to do."

  "It doesn't really bother me. But I probably should get back to work."

  "No problem. Thanks for taking the time. Now, and before."

  "Anytime. Later, A.J. Let me know how everything goes!"

  "I will."

  The image of the paleontologist vanished, and A.J. dug in. Now that he realized how excited he was, he was impatient to get back. There were things to do, and he was the one to do them!

  Eric Flint Ryk E. Spoor

  Boundary

  Chapter 14

  Release of ISM units completed successfully. All units showing on the green."

  "That's the way to do it," A.J. said triumphantly. "Okay, time to get to real work."

  A.J. checked the release pattern and observed that the Faeries were in proper station-keeping mode with respect to each other. Pirate was already moving away to a safe distance preparatory to making its final deorbit burn.

  That was fine with A.J.. He knew what he was going to do with the Faeries, but he wanted to tweak all the instructions to reflect exactly the situation around Mars. The release had occurred just one hundred and sixty thousand meters from Phobos-a bit less than a hundred miles.

  The Faeries were equipped with electric or, as A.J. preferred to call them, "ion" drive systems. They were low in actual thrust-the optimized designs on the Faeries would, at full power, shove the sensor platforms forward with an acceleration of all of one-fiftieth of a gravity. But the ion drives made up for it with specific impulse ratings that were beyond even the wildest fantasies of nuclear rocket enthusiasts, measured not in hundreds but in thousands of seconds. That made it possible for objects like the Faeries, which were small enough that A.J. could have picked them up and carried them, to hold sufficient reaction mass to travel significant distances and stop at their destinations. It was critical to give them that ability, since the availability of high-thrust drives such as compressed gas, rockets, or similar approaches was tremendously limited on small probes.

  As everything was on the green, A.J. was going to have one of the Faeries-Ariel-run ahead of the pack, trying to reach Phobos at maximum speed, while the others would take much more leisur
ely approaches. This would be a test of the Faeries' navigation skills, the precision of his programming and the engineering departments' design work, and of the efficiency and precision of the drive system. At that distance

  …

  Close enough for minimal orbital mechanics to take part, 1/2at^2, we get… um… a little over twenty-one minutes, full acceleration for 10.66 minutes and a smidge, flip and decel for same amount of time.

  The other Faeries-Titania, Tinkerbell, Sugarplum, and Rane-would follow at a more sedate pace, getting to their stations around Phobos in a few hours. He worked the precise numbers and course data carefully, then transmitted the orders to the Faerie Fleet.

  "Well, in a while we'll start seeing some action," he said, leaning back and glancing around. "Say, about an hour. Though if you'll watch Titania and Rane's transmissions, you'll get to see the Pirate do its burn and start true deorbit. They'll try to hold the image as long as possible, another test we programmed in them before we started. That will demonstrate how well they can track. Tink's doing some GPR on Phobos before approach, while Sugarplum will be seeing if I can get good returns from Mars with the same equipment. Probably not, but it's worth a try."

  "Where's Pirate landing?"

  "We're combining science and sightseeing. Landing track will take Pirate right down the Valles Marineris, and our target landing site is somewhere near the Melas Chasma. There's a lot of interesting possibilities to be found at the bottom of the Valles, and Melas Chasma has some of the best potential for all sorts of stuff, including mineral finds of various sorts. You'd have to ask some of the others back at Ares for more details. I'm not as up on that as on other things."

  "How long do you think you'll be working here tonight?" Diane asked, curious.

  A.J. laughed. "Possibly all night. Or until the caffeine runs out. I may not be able to control them like a video game, but watching what they're doing and making decisions as I start getting a real picture of what Phobos is like is a job that can't be entirely left to machines. I don't think I'm going to want to just hand it over to automatics for quite a while yet. Until I know what I'm dealing with, I won't-and the Faeries won't-know what the best approaches are, especially for locating the best places to land the base materials."

  That was, of course, the main purpose of the whole exercise: to survey Phobos with an accuracy and detail never before attempted, including interior imaging if possible, so that the best location for the Phobos Base could be determined.

  "Once the data really starts flowing, no one bother me. I'm putting my earphones on now." He suited action to words, and the exuberant sounds of Tenkuken's Battle for Heaven blotted out any possibility of being interrupted short of someone physically poking him.

  The latter would also be difficult as he had now brought up a temporary cubicle. That minimized disturbance in both directions, since it not only prevented people from casually walking up to him to ask questions, but also screened him from view and at least partially from hearing. A.J. had a habit of talking to himself or playing VR games while waiting for the next round of Real Work. It was only a matter of courtesy to try to minimize the amount of such antics his co-workers were exposed to.

  Initial GPR data was starting to come in from Tinkerbell and Sugarplum. That was what he was currently interested in, but he left the feed from Titania and Rane up so that anyone interested could track Pirate's progress.

  Excellent, the returns were coming in loud and clear from Phobos. It wouldn't be too long before he could start building up an idea of what he had there. Surprisingly, he was actually getting some usable returns coming back from Mars. Well, with the lowest orbit of a natural satellite known-less than six thousand kilometers-he wasn't trying to scan from nearly as far out as he would otherwise. He stored that data for later analysis; it wasn't part of the main project.

  A shadowy image began to build up on his VRD. Phobos' density was known to be very low-not even high enough to be mostly carbonaceous rock. The moonlet's composition was a mixture of rock and ice, or it had large hollows inside. Either was a fairly likely possibility. The theory was that both Phobos and Deimos were captured outer-system bodies, possibly "burned out" comets or something similar.

  Privately, A.J. had bet himself that it was a combination-there would be some hollows, and some ice as well. The latter was close to being a sucker bet, as some probes, notably the ill-fated Soviet Phobos probes of the late twentieth century, had actually detected some water outgassing from the little moon.

  The GPR probes were slowly gathering enough data to start generating a 3-D model of Phobos. The moonlet was roughly oval in shape, with the giant ten-kilometer crater Stickney showing how close the little moon had come to being shattered eons ago. The model was slowly solidifying. Now it was a cloud of gray with just tantalizing hints of structure, but as time went on, he was sure he'd get more out of it.

  Looking at the rest of the feeds, it was clear that he wouldn't have much to do-even just on the thinking end-for another half-hour at least, maybe more. So he keyed the system up to do alerts only when various tasks were complete, and logged on to the Elemental Flame VRRPG (Virtual Reality Role Playing Game) server net.

  After about an hour with no particular alerts from the system,

  A.J. switched over for a glance. What he saw caused his character Severn Four-Winds to exclaim "What the hell is that?" This necessitated some out-of-character explanation and a quick log-off.

  "What is that?" he asked himself again.

  The 3-D model of the miniature moon had become much more solidly detailed, since its ghostly first appearance of an hour or so ago. But the details that could be made out were…

  Peculiar, to say the least. Some areas of the interior were blank, as though the GPR waves couldn't penetrate. That was pretty odd given what was normally required to screen out radar waves. There were rounded and blocky outlines, long curving lines seeming to radiate out from various points, and things that appeared to be hollows of a wide, flat nature.

  A.J. started talking to himself. "Hmm. Well, this is over near Stickney. Result of collision? Maybe. It does radiate outward. I wonder if the other radiative areas coincide with impact events. It's the blank areas that are really funny."

  A.J. wasn't really that knowledgeable with regard to astrogeological dynamics, but to his untutored eye it looked like half-melted conglomerate with crystal inclusions.

  "Which, come to think of it, might not be far from the truth," he muttered. "If the things were outer-system, they must've been something like comets, so parts would certainly be melting at perihelion. And they'd be moving so fast that normally they couldn't be captured by something as small as Mars. So maybe they hit something-something that caused serious melting. Hmm… maybe… what if Deimos hit Phobos, or something like that? I'll have to get one of the orbital mechanics guys to model it. How fast would these things be moving if they came in from outsystem, and what would it take to get them captured by Mars?"

  He checked the disposition of the Faeries. Ariel was very close to the surface of Phobos, no more than a mile off. The other probes had stopped about six or seven miles away and were bracketing the nearly fourteen-mile-long moon in a designed attempt to ensure that no point on Phobos' surface would go unmapped.

  "Okay, let's get fancier."

  A.J. considered the arsenal of sensors at his disposal. The Faeries were, in some ways, the most advanced instrumentation packages ever constructed, and they had an awful lot to offer. The primary modality on Earth was sight, so naturally the Faeries were well equipped with cameras. Visible light, ultraviolet and infrared-with their optics sealed between synthetic diamond windows for protection.

  Unfortunately, the real detail he needed-down to a foot or less-he couldn't get at this distance. With a field of vision of only sixty degrees, he wasn't going to get much better than five feet or so, even with interpolation and super-resolution tricks. Narrower FOVs would have been better, but the tradeoffs involved had torpedoed t
hat. He'd even had the engineers try a synthetic FOV approach, but that ran into problems with light-gathering capability which would take too long to solve.

  "If only I could use something with decent resolution," he muttered, not for the first time.

  The problem was an old one, dating back to the onset of space exploration. There was almost always a big lag between what technology could do on the surface and what you could get to work up there, with the radiation, vacuum, and other things to cope with. The gap had only gotten bigger in the last decade or so, because with most of the advances hinging on how much smaller and more efficient they could make the gadgets, they'd been getting progressively more sensitive to minor problems.

  Tons of minor problems were pretty much what space handed you all the time. Cosmic rays, outgassing from vacuum, the list went on and on. And there was no corner store on the way to pick up a replacement. That meant that you couldn't afford to use something that wasn't fully space qualified on an interplanetary voyage. For a jump to orbit and back down, maybe, but not across a hundred million miles.

  So, for the Faeries, A.J. was stuck with something not much better than he could've gotten on the street twenty years ago. Barely twenty-five megapixels in the visible, and worse in the IR and UV spectra.

  But there was no point regretting the inevitable. A.J. had IRnear, mid, and far-along with visible and three UV bands. He had GPR, which would certainly be needed. Other frequencies of radio might prove useful, especially if he used the X-ray approach-have one transmitting and the other receiving. Measurement of heat signatures and any chemical emissions would be vital. If there were major caverns or differing composition beneath the surface-which did, as suspected, seem to be covered with about a meter of regolith-the heat absorption and radiation should show some differing patterns.