The Compleat McAndrew

FOURTH CHRONICLE: The Manna Hunt

We had been working hard for two months, preparing for the first long trip. Neither McAndrew nor I would admit to feeling excited, but every day I could see the pleasure and anticipation just bubbling up in him. I doubt that I was any harder to read.

It meant sixteen-hour work spells, day after day, checking every detail of the ship and mission. On an exploration that would take us away for four months of shipboard time and almost nine years of Earth-time, all the thinking had to be finished before we left the Institute.

Finally the launch date was only four days away.

That made the news of cancellation — when they plucked up the courage to tell us about it — hard to take.

I had been over on the Hoatzin, checking the condition of the big massplate at the front of the ship. It took longer than I expected. By the time I flew my inspection pinnace on its ten thousand kilometer hop back to the Penrose Institute we were well into the sleep period. I hadn’t expected anyone in the dining hall when I slipped in to dial a late meal — and certainly I didn’t expect to find Professor Limperis in close conversation with McAndrew.

“Working late—” I said. Then I saw their faces. Even Limperis, black as he was, looked drawn and a shade paler.

I sat down opposite them. “What’s happened?”

McAndrew shrugged without speaking and jerked his head towards Limperis.

“We’ve had a directive from USF Headquarters,” said the older man. He seemed to be picking his words carefully. “Signed by Korata — right from the top. There was a meeting last week between the Food and Energy Council of Earth and the United Space Federation. They called me two hours ago. The Penrose Institute is instructed to support certain high priority Council activities. This requires that we—”

“They’ve cancelled us, Jeanie,” cut in McAndrew harshly. “The bastards. Without one word of discussion with anybody here. Our Alpha Centauri mission is dead — finito.”

I gawped at Limperis. He nodded in an embarrassed way. “Postponed, at least. With no new date set.”

“They can’t do that.” I was beginning to feel my own anger rising. “The Institute doesn’t answer to the Food and Energy Council, how the hell can they claim to order you around? This is an independent organization. Tell them to go away and play with themselves. You have the authority to do that, don’t you?”

“Well…” Limperis looked even more embarrassed. “In principle, Captain Roker, it is as you say. I have the authority. But you know that’s an oversimplification of the real world. We need political support as much as any other group — we rely partly on public funding. I like to pretend that we’re pure research, answering to no one. In practice, we have our own political constituency in the Councils. I tried to explain this just now” — McAndrew grunted and glowered down at the table — “to point out why I can’t really fight it without losing an awful lot. Three of our big supporters, Councilors who’ve done us big favors in the past, called me ten minutes after we got the first word. They want to use their credit on this one. The Alpha Centauri mission is off. The Council needs the use of the Hoatzin for other purposes.”

“No way.” I leaned forward until our faces were only six inches apart. “That’s our ship — we’ve slaved over it. If they think they can call in and take it away from me and Mac without even asking, and leave us—”

“They want you, too, Jeanie.” Limperis leaned back a bit. In my excitement I was spitting all over him. “Both of you. The orders are very clear. They want you and McAndrew and the ship.”

“And what the hell for?”

“For a mission of their own.” He looked more baffled than irritated now. “For a mission so secret they wouldn’t tell me anything about it.”

That was the first shock. The others dribbled in one by one as McAndrew and I made our way from the Penrose Institute to the headquarters of the Food and Energy Council.

The Institute had been parked out near Mars orbit. With the Hoatzin, and its hundred gee drive, or even with one of the prototypes like Merganser at fifty gee, we could have been to Earth in half a day. But Professor Limperis still insisted that the McAndrew Drive should never be employed in the Inner System, and McAndrew himself backed that decision completely. We were stuck with a slow boat and a ten day journey.

Surprise Number One came soon after we powered away from the Institute. I had assumed that we would be running a confidential mission for the Energy Department of the full Food and Energy Council. We had worked together on high-energy projects in the past, and I knew McAndrew was a real expert on the subject. But our travel documents instructed us to report to the Food Department. What did food programs need with a theoretical physicist, a spacecraft captain, and a high-acceleration ship?

Three days from Earth we were hit with another surprise. The information came in as a brief, impersonal directive that could be neither amplified nor questioned. I would not be the captain of the new mission. Despite the fact that I had more experience with the McAndrew Drive than anyone else in the System, a Food Department official would give me my orders. I became even angrier when, two days from Earth, we learned the rest of it. McAndrew and I would serve as “special advisors” reporting to a crew from the Food and Energy Council. We would have about as much decision-making authority on the mission as the robochef. I had descended from captain to cabin boy.

For me, maybe they could persuade themselves that it was a reasonable decision; some people have more deep space experience than I do (but not much more) and you could say that my talent is nothing more than tricks for staying alive and out of trouble. But McAndrew was another matter. To assign him a role as a simple information source suggested an ignorance or an arrogance beyond my belief.

All right, so I’m a McAndrew fan; I won’t deny it. When I got to Earth I would have words with the bureaucrats of the Food Department.

I needed to talk it out with somebody, but Mac was no use. He wasn’t interested in arguments on nontechnical subjects. Instead, he retreated as usual into his private world of tensors and twistors, and despite my own respectable scientific background I couldn’t follow him there. For most of the journey he sat slack-jawed on his bunk, perfectly content, gazing at the blank wall and performing the invisible mental gymnastics that had earned him his reputation.

That sort of thinking is beyond me. I spent the long hours brooding, and by the time we were led into the Council’s offices I was loaded for bear.

The Food Department enjoys a bigger staff and budget than anything else in System Government, and the opulence of its fittings was quite a contrast to the spartan furnishings of the Institute. We were conducted through four luxurious outer offices, each with its own secretaries and screening procedure. Ample working space spoke of prestige and power. The room we finally came to held a conference table big enough for forty people.

A woman was seated alone at the massive desk. I looked at her elegant dress, beautifully made-up eyes and carefully coiffured hair, and I suddenly felt scruffy and out of place. Mac and I were dressed for space work, in one-piece beige coveralls and loafers. My hair had been cropped to a few centimeters long. His thin, straggly mop as usual dipped untidily over his high forehead. Neither of us was wearing a touch of make-up.

“Professor McAndrew?” She stood up and smiled at us. I glowered back at her. “And Captain Roker, I assume. I must apologize for treating you in such cavalier fashion. You have had a long trip here, and no adequate explanation.”

Good disarming waffle, the sort you get from an experienced politician or the highest level of bureaucrat, but her smile was broad and friendly. She came forward and held out a pudgy hand. As I took it I made a closer inspection of her appearance: thirty-five years old, maybe, and a bit overweight. Perhaps this messy situation wasn’t her fault. I restrained my scowl and muttered conventional words of greeting.

She gestured us to sit down.

“I am Anna Lisa Griss,” she went on. “Head of Programs for the Food Department. Welcome to Headquarters. Other staff members will join us in a few minutes, but first I want to point out the need for secrecy. What you will learn here cannot be mentioned to anyone outside this room without my permission. I will come to the point at once. Look at this.”

She exuded an air of complete control. As she was speaking the lights dimmed and an image became visible on the screen at the far end of the room. It showed a column of calendar years, and alongside it two other columns of figures.

“Total System food reserves, present and projected,” said Griss. “Look at the trend — it’s a log scale — then look particularly at the behavior thirty years from now.”

I was still trying to assimilate the first few numbers when McAndrew grunted and put his hand up to his face.

“That’s ridiculous,” he said. “You’re showing a factor of two drop in less than three decades. What’s the basis for that projection?”

If she felt surprise at his speed of response, she didn’t show it. “We included population patterns, available acreages, plant yields, and capacity to manufacture synthetics. Would you like to see the details on any one of them?”

McAndrew shook his head. “Never mind the details. That’s disaster and starvation flashing on your screen.”

“It is. It’s the reason that you are here.” She brought the lights back up to what I regarded as a dim, conspiratorial level and dropped her voice to match. “You can imagine the effect when that projection becomes public knowledge, especially if no one can see any way out. Even though we’re talking about many years in the future, we’d see stockpiling — probably food wars.”

I was feeling a growing anger. There had been rumors of a major future food shortage flying around the System for a long time. The Administration had denied every one, dismissing all gloomy forecasts as alarmist.

“If you’re correct in your projections, you can’t keep this a secret,” I said. “People have a right to know so they can work on solutions.”

McAndrew frowned at me, while Anna Lisa Griss gave me a quick probing glance (no smile now) and raised her dark eyebrows. The man’s easy, her look said, but this one needs persuading.

“The problem is clear enough,” she agreed. “It has been known to my group for almost a decade. Fairly soon it may be obvious to everybody. But it’s the possible solution I want to talk about now. And involving the general public wouldn’t help a bit — there’s no chance that they could provide new insights.”

I didn’t like her superior manner, but in spite of my irritation I was becoming interested. “It has to be a supply-side answer,” I said. “The population growth won’t budge.”

“Obviously.” She smiled again, a bit too broadly, and sneaked a look at her watch. “But think about that supply side. We’d like to increase the planted acreage, of course. But how? We’re using every spare inch, unless we can move the lunar agricultural experiments to massive production — and nobody feels optimistic about that. Plant yields are as high as they will go — we’re seeing bad effects of plant overbreeding already. No hope there. So what’s left?”

Before we could chance an answer or she could provide one, the door behind us opened. A skinny man with plastered-down grey hair entered and stood deferentially at the threshold.

“Come in, Bayes.” Anna Lisa Griss looked again at her watch. “You’re late.”

“Sorry.” He remained at the door, hesitating.

“I began without you. Come in and sit down.” She turned to face us without offering introductions. “There was one area still to be examined: alternative supplies of organic materials that might easily be converted to food. Six years ago, everyone thought that was a hopeless avenue. Now, with the Griss-Lanhoff Theory” — I could hear the capital letters in her voice as she proclaimed the name — “we have new hope.”

I was watching Bayes’ face as she spoke. His lips tightened when Anna Lisa Griss pronounced the name of the theory, but he remained silent.

McAndrew cleared his throat.

“I’m afraid that I’m not as well up on the literature of food production as I ought to be,” he said. “Lanhoff’s a familiar name. If it’s the same person, I knew him fairly well ten years ago, when he was working on porphyrin syntheses. What’s he doing now?”

“We don’t know. Maybe you can help us to find out.” She leaned forward and looked at us intently. “Lanhoff has disappeared — out in the Halo, testing our theory. Two weeks ago I learned that you have available a high-acceleration ship with an inertia-less drive.” (I saw McAndrew wince and mutter “not inertia-less” to himself.) “We need the use of that, for a mission of the highest priority. We have to find out what happened to Lanhoff’s project. Three days from now we must be on our way to the Halo.”

It said something for the lack of efficiency of the Food Department that they would drag McAndrew and me all the way to Earth for a meeting, then shuttle us back to the Penrose Institute and the Hoatzin on a Government-owned ship less than four hours after we arrived. Anna Lisa Griss would follow to the Institute in another and even fancier vessel, but Bayes went with us to continue the briefing on the way. Without his boss around he lost his intimidated look and became a much cheerier person.

“Let’s start with Lanhoff’s ideas,” he said. “Though after listening to Anna back in her office it’s apparently going to be called the Griss-Lanhoff Theory, at least while Lanhoff’s not on the scene. I’ll keep it short, but I’m not sure where to begin. In the Halo, I guess. Professor McAndrew, do you know anything about the Halo?” He cackled with laughter at his joke.

Griss had asked McAndrew that same question when she was giving us our first briefing. I had watched Bayes’ eyes bulge with astonishment. I felt the same way myself. McAndrew probably knew more about the Halo and the outer parts of the extended Solar System than anyone, living or dead — he had developed the entire theory that predicted the existence of the kernel ring, the broad belt of Kerr-Newman black holes that girdles the ecliptic at four hundred AU, ten times the distance of Pluto. And of course he had travelled out there himself, in the first test of the McAndrew balanced drive. I assumed that any scientist worth the name would know all about McAndrew and his work, but apparently Anna Lisa Griss proved me wrong.

McAndrew laughed. He and Will Bayes had needed only ten minutes alone together to discover a mutual fascination with bad jokes, and they were getting along famously. I thought ahead to a long trip with the two of them and shuddered at the prospect.

“Lanhoff wandered into our offices six or seven years back,” went on Bayes after he had had a good giggle at his own wit. “He’d been analyzing the results of Halo remote chemistry probes. Didn’t you do some of that yourself, a few years ago?”

McAndrew rubbed at his sandy, receding hairline. “Och, just a little bit. I wanted to find power kernels, not low-density fragments, but as part of the survey we sneaked in a look at some other stuff as well. Most of the Oort cloud’s so poorly surveyed, you know, it’s a crime not to explore it whenever you have the chance. But I never looked out more than a few hundred AU — it was before we had the drive, and probes were too expensive. I’m sure Lanhoff had all my results to work with when he started.”

“He certainly knew your work,” said Bayes. “And he remembered you well. You made quite an impression on him. He’s an organic chemist, and he had been looking at all the data on the Halo, and plotting body chemical composition as a function of distance from the Sun. He has a special algorithm that allows him to look at the fractional composition of each object — I think it came from Minga’s team. You probably don’t remember Minga, he never published much himself. I met him once or twice, way back… no, maybe I’m thinking of Rooney. You know, he was the one who did the high-energy work, I think it was for the Emerald Project, wasn’t it? Yes, I think so…”

It’s probably a kindness if I edit Will Bayes’ briefing of McAndrew and me. He tried hard enough, but everything he said reminded him of something else, and that something else had to be explained, too, and all the people involved in it reminded him or other people, and what they had done. Regression, ad infinitum.

We didn’t mind too much, with a two-day journey before we were back at the Institute, but I must say I thought a bit more kindly of Anna Griss before the trip was over. Staff meetings with Bayes must be hell.

Boiling Will’s verbiage down to a minimum, it was a simple story: Lanhoff had done a systematic chemical analysis of the cometary Halo, from its beginnings beyond the Edgeworth-Kuiper Belt, all the way to the fading outer edge nearly half a light-year away, where the Sun’s gravitational hold is so weak that the frozen bodies drift around in orbits with periods of millions of years.

That’s the Oort cloud, a great ball of loosely-held matter centered on the Sun. There are several hundred billion comets out there, ranging from near-planet-sized monsters a few hundred kilometers across to snowballs no bigger than your fist. Chapman’s Rule applies as well to the cometary Halo as it does to the asteroid belt: for every object of given diameter, there are ten objects with one-third of that diameter.

The Halo has been described and studied since the middle of the twentieth century, but Lanhoff’s interests were different. He divided the solar vicinity into regions of different distances and inclinations to the plane of the ecliptic, and he looked at the percentage of different organic materials within each orbital regime. Naturally, with a trillion objects to work with he could only look at a tiny sample of the total, but even so the analysis took him eight years. And he found something new and surprising. In a part of the Halo about 3200 AU from the Sun, running out to maybe 4,000 AU, the complexity of chemical compounds increases enormously. Instead of simple organic molecules like cyanogen, formaldehyde, and methane, his program told him he was finding higher compounds and complex polymers — macromolecules like polysaccharide chains.

“Like what?” At that point in the discussion I had interrupted Will Bayes’ rambling. Organic chemistry is low on the list of educational priorities for controlling a spacecraft.

“Organic polymers,” said McAndrew thoughtfully. He had been frowning hard as Bayes talked of the chemical composition. “Chains of glucose molecules, to make starches and cellulose.” He turned back to Bayes. “Did Lanhoff find any evidence of porphyrins, or nitrogen compounds like purines and pyrimidines?”

Bayes blinked. “You seem to know all about this already. Did Anna already brief you? Lanhoff’s work is all supposed to be a big secret.”

I had some sympathy with him. Briefing McAndrew is an unrewarding experience. At the end he seems to know everything you know and be able to explain it and apply it better. Now Mac was shaking his head and looking puzzled.

“She didn’t mention any of this to us. But I knew most of it years ago. Not the particular place in the Halo where we might find complex organic materials, but at least the fact that they might be there. It’s not a new theory at all. Hoyle suggested it more than a hundred years ago. I just don’t understand why there’s anything secret about it. A finding like this one ought to be available to anyone.”

“There’s a reason. Wait until you know Anna Griss a bit better and you’ll understand.” Bayes was looking outside for his first glimpse of the Hoatzin, which was now only a couple of hundred kilometers away. “She’s the hardest worker I know, but she’s super-ambitious. She wants to run the whole Council someday — tomorrow, if she had her way. When Lanhoff came to her with his proposal, the first thing she did was hit it with a classified label.”

“Didn’t anyone argue with her?” I said.

“No. Try it. It’s not something you’ll do more than once. There were a few mutterings, that was all. Anna offered some positive incentives, too. She thinks this will make her famous, and push everybody in the Department ten rungs up the management ladder.”

“Just because we’ve got a bit more information about the composition of the Halo? Not much chance of that.” McAndrew snorted his disbelief.

“No.” Bayes was still peering out of the port. “Lanhoff persuaded her that he had the only answer to the System food problem. All he needed was money and a ship, and USF permission to make some orbit changes to a few bodies out in the Halo. Good God!” He turned back from the scope. “There’s the oddest-looking ship out there. Surely we’re not proposing to chase after Lanhoff in that thing?”

Lanhoff’s suggestion sounded reasonable until you sat down to think about it. Out in the Halo, off where the Sun was nothing more than an extra-bright star, mountains of matter drift through space, moving to the tug of a faint gravitational current. Most of them are frozen or rocky fragments, water ice and ammonia ice bonding metals and silicates. But swarms of them, in a toroidal region three hundred billion miles from Earth, are made of more complex organic molecules. If Lanhoff were correct, we would find an endless supply of useful compounds there — all the prebiotic materials from which foodstuffs are easily made. They needed only warmth and a supply of the right enzymes to serve as catalytic agents. Cellulose, polypeptides, carotenoids, and porphyrins could be transformed to sugars, starches, proteins, and edible fats. The food supply of the whole solar system would be assured for a million years.

Now sit down and think about it again. How do you seed a hundred million worlds and turn them to giant candymountains, when the nearest of them is so far away. How do you heat them; how do you get them back where they will be useable?

If you are Arne Lanhoff, none of those questions will deter you. The enzymes you need are available in small amounts in the inner system; once a body has been seeded and heat is available from a fusion reactor, enzyme production can proceed at an explosive pace. It will suffice to begin with just a few hundred thousand tons of the right enzymes, and make the rest where the supply of raw materials is assured. The types of enzymes needed to split polymer chains are well known, but the only sort of ship that can carry this much load is a boost-and-coast vessel with a maximum short-duration acceleration of only two-tenths of a gee. So be it. Plan on a trip out to the Halo that will take a couple of years, and allow another year or two to trundle around from one cometary body to the next, seeding and performing necessary orbital adjustments. The continuous-thrust engines that will be attached to each body add another two million tons to the ship’s initial payload. So be it. Fusion heaters to warm the frozen interiors will add a million more. Don’t worry about it. For a project of this size and importance, the Food and Energy Council will find the money and equipment.

McAndrew had shaken his head when Will Bayes described the plan to place the seeded bodies into radial orbits, thrusting in toward the Sun. “Man, do you realize what it will take to stop one of them? We’ll be trying to catch a billion tons travelling at two thousand kilometers a second.”

“Arne Lanhoff knew that before he left. He was planning just enough drive to bring them to the Inner System in twenty years. By that time they’ll be warmed and transformed in content.” Bayes smiled contentedly. “He felt sure that you’d find ways to catch them and slow them. It’s the sort of thing your group finds challenging.”

“Challenging! He’s insane.” But two minutes later McAndrew was miles away, working on his new puzzle. Arne Lanhoff knew his man rather well.

The ship that had left the Inner System four years ago did so with no fanfares or publicity. The Star Harvester was a massive set of linked cargo spheres with electromagnetic coupling. Each Section had an independent drive unit powered by its own kernel. It was quite similar to the Assembly that I pilot on the Earth-Titan run, and I was glad to know that I’d have no trouble handling it if the need arose.

That need might well arise. The Food Department had received regular communications from the Star Harvester crew during the long trip out — two years Earth-time, and the ship was too slow to make it noticeably shorter in shipboard time. Lanhoff had finally reached his first suitable target, a fifteen-kilometer chunk of ice and organics. He had officially named the body Cornucopia, planted the enzyme package, the fusion furnace, and the drive, and then started it on the long drop in towards the Sun. Without the drive it would fall for millennia. With a little continuous-thrust assistance Cornucopia would be crossing the orbit of Jupiter sixteen years from now. By that time it would be a fertile mass of the raw materials of nutrition, enough to feed the entire solar system for five years.

“No problems. Complete success in all phases,” read Arne Lanhoff’s message as they moved on to the next selected target, a mere five hundred million miles away.

The mission had operated perfectly for another five targets — each one named, processed, and directed toward the Inner System. Ambrosia; Harvest Festival; Persephone; Food of the Gods; and Demeter.

Then the pattern was broken. The seventh target had been reached ninety days ago. After an initial message announcing contact with the body Manna, a huge organic fragment sixty kilometers in length and incredibly rich in complex compounds, Star Harvester became inexplicably silent. A query beamed to it from Triton Station fled off on its nineteen-day journey, and an automatic signal of message receipt finally returned. But no message originated in the ship’s transmission equipment. Arne Lanhoff and his crew of four had vanished into the void, three hundred billion miles from home.

Our troubles didn’t wait until we were out in the Halo. As soon as Anna Lisa Griss arrived on board the Hoatzin, only six hours before our scheduled departure time, we had a problem. She looked around the living quarters disbelievingly.

“You mean we’re supposed to stay in this little space — all of us? It can’t be more than three meters across.”

“Nearer to four.” I paused in my run-through of firing sequence checks. “We left information about that with you before we came here — didn’t you look at it?”

“I looked at the size of the ship, and the column for the living quarters was hundreds of meters long. Why can’t we use all of it?”

I sighed. She had the authority to commandeer the Hoatzin but had never bothered to learn the first thing about how it operated.

“The living-capsule moves up and down that column,” I said. “Farther from or closer to the mass disk, depending on the ship’s acceleration. We can put the supplies outside the capsule area, but if we want to live in a one-gee environment we’re stuck with this part — it’s not bad, plenty of space for four people.”

“But what about my staff?” She gestured at the five people who had followed her into the Hoatzin. I realized for the first time that they might be more than merely carriers of luggage.

“Sorry.” I tried to sound it. “This ship is rated for a four-person crew, maximum.”

“Change it.” She gave me the full force of her imperial manner. I suddenly understood why Will Bayes chose not to argue with her.

I stared back at her without blinking.

“I can’t. I didn’t make that rule — check with the USF back at Lunar Base if you like, but they’ll confirm what I’m telling you.”

She took her lower lip between her teeth, turned her head to survey the cabin, and finally nodded. “I believe you. Damnation. But if there is a four-man limit we still have a problem. I need Bayes and I want my own pilot. And I need McAndrew. You’ll have to stay behind.”

She didn’t look at me this time. I took a deep breath. I didn’t want to do it, but if we were going to bang heads we might as well get it over with. Now was as good a time as any.

“I suggest that you discuss this with McAndrew,” I said. “Better talk to your pilot, too, while you’re at it. I think you’ll find that Mac will refuse to go along without me — just as I wouldn’t go without him. This is not a conventional vessel. Ask your own pilot how many hours of experience he has with the McAndrew Drive. Mac and I have essential experience and skills for the successful performance of this mission. Take your pick. Both, or neither.”

My voice sounded trembly. Instead of replying she turned to head for the steps to the lower level of the living-capsule.

“Prepare us for departure,” she said over her shoulder as she went. Her voice was so calm that I was shocked by my own tension. “I will talk to Bayes. He must assume additional duties on this project.” She turned again when just her head and shoulders were visible. “Did you ever consider taking a job down on Earth? You have abilities that are wasted out here in the middle of nowhere.”

I swivelled my chair to face the console screen and wondered what sort of victory I had won — if any. Anna Lisa Griss was wise in the ways of political infighting, while I was a raw novice. But I was damned if I’d give up my place on this trip without a struggle. The ship was easy to handle, but I’d never admit that to Anna Griss.

Will Bayes came in to stand beside me while I was still having trouble getting my attention back to the status reports.

“Now you’ve done it,” he said. “What did you say to her? I’ve never seen her in such a weird mood. I can’t read her at all. She just told Mauchly and the rest of her staff to get back to Headquarters — no explanation. And I’ve been given double duty for the duration.”

I ran the trajectory parameters out onto the screen, jabbing viciously at the buttons. Then I gave him a quick sideways glance. “I had to make a choice. Which would you rather have: Anna Lisa Griss in a peculiar mood, or a ship run by people who don’t know the McAndrew Drive from a laser-sail?”

He grunted and stared gloomily at the screen. “That’s not an easy decision. You’ve never seen Anna when she’s really annoyed. I have. Let me tell you, it’s not something I want to go through again.” He leaned forward. “Hey, Jeanie. Surely that’s not the plot of our flight out you’ve got on the display there.”

“It certainly is.” I rotated axes so that all coordinates were in ecliptic spherical polars and stored the result. “Don’t you like it?”

“But it looks so simple.” He moved his finger along the screen. “I mean, it’s just a straight line. Not a real trajectory at all. What about the Sun’s gravitational field? And you’re not making any allowance for the movement of Manna while we’re flying out there.”

“I know.” I loaded the flight profile to main memory and as I did so the knot in my stomach seemed to loosen. “That’s why I’ll be piloting this ship, Will, rather than one of your buddies. We’ll be accelerating away from the Sun at a hundred gee, agreed? Did you know that the Sun’s acceleration on us here near Mars orbit is only one three hundred thousandth of that? It has tiny effects on our motion.”

“But what about Manna’s movement in its orbit while we’re on the way there? You’ve ignored that as well.”

“For two reasons. First, Manna is so far out that it’s not moving very fast in its orbit — only half a kilometer a second. More important, we don’t know how far Lanhoff’s team went in processing Manna. Is the body in its original orbit, or did they start it moving in toward the Sun?”

“I’ve no idea.”

“Nor have I. The only thing we can do is fly out there and find out.”

I looked at the clock. Time to get moving. “Better say your goodbyes,” I went on. “There’ll be plenty of chances for us to talk to each other in the next couple of weeks. Probably too many. Two hours from now we’ll be on our way. Then we’ll be deaf to outside signals until we’re out in the Halo and turn off the drive.”

“Is that so?” He looked intrigued. “But what about orders that come—”

“Bayes.” Anna Griss was calling softly from below.

Will was gone before I could swivel my chair.

I don’t envy the life of the Downsiders, ten billion of them crawling over each other looking for a little breathing space. But there are certain experiences available on Earth and nowhere else in the Solar System.

For instance, I’m told that, during the great circular storms that sweep from the Earth tropics to the northern latitudes, there is an area at the very center — the “eye of the hurricane” as the Downsiders call it — where the wind drops to perfect stillness and the sky overhead turns to deep blue. That’s something I’d like to see, just once.

The eye of the hurricane. That was the area of the living-capsule surrounding McAndrew during the Hoatzin’s flight out to rendezvous with Manna.

With me, Anna Griss was in constant battle.

“What are you talking about, no messages?” she said. “I have to be in daily contact with Headquarters.”

“Then I’ll have to switch off the drive,” I explained. “We can’t get signals through the plasma shell.”

“But that will slow us down! I told Headquarters that we’d only be away for one month — and it’s a two-week trip each way even if we keep the drive on all the time.”

We were standing by the robochef and I was programming the next meal. It took a few seconds for her last statement to penetrate.

“You told Headquarters what? That we’ll only be away for a month?”

“That’s right. Three days should be long enough to find out what’s happening to Star Harvester. You said that yourself, and McAndrew agreed.”

I turned to face her, noticing again the care she took to make her appearance as well-groomed and attractive as possible.

“Three days should be long enough, sure it should. But you’ll be away for a lot more than a month. The trip is two weeks each way in shipboard time. It’s twenty-five days each way in Earth-time. There’s no possible way you can get back home in a month.”

Her face flushed red and her eyes glowed — she looked more attractive than ever. “How can that happen?”

“I don’t know, but it’s standard physics. Ask McAndrew.” (I knew well enough, but I’d had more than I wanted of this conversation.)

It was like that all the time. We found it hard to agree on anything, and it became clear as soon as we were on the way that Anna Griss was used to delegating and not to doing. Poor old Will Bayes did triple duty. Luckily there was not too much that could be done without a communications link to Earth — except shout at Will and keep him on the run.

Yet McAndrew — I thought at first I was imagining it — McAndrew was the eye of the hurricane. When she was within two yards of him, Anna Griss became all sweetness and light. She humbly asked him questions about the drive and about time dilation; she deferred to his opinions on everything from diet to Dostoevski; and she hung first on his word and then on his arm, blinking her eyelashes at him.

It was sickening.

And McAndrew — the great lout — he lapped it up.

“What’s she doing?” I said to Bayes when the other two were out of earshot. “She’s making a fool of herself.”

He winked at me. “You think so, and I think so — but does he think so? Before we left she told me to get a full dossier about him and bring it on this trip. She’s been reading it, too. You have to know Anna. What she wants, she gets. Wouldn’t look bad for her personal records, would it, to have a five-year cohab contract with the most famous scientist in the System?”

“Don’t be silly. She doesn’t even like him.”

“She does, you know.” He stepped closer and lowered his voice. “I know Anna. She has appetites. She wants him, and I think she’d like a cohab contract.”

I snorted. “With Mac? That’s ridiculous! He belongs to — to science.” And I fully believed it, until one morning I found myself applying a pheromonal amplifier behind my ears, and dressing in a new lime-green uniform that fitted a lot closer than my standard garb.

And McAndrew — the great lout — he never noticed or said one word.

While this was going on, we were hurtling outward away from the Sun. With our acceleration at a hundred gee, the living-capsule was snuggled in close to the massplate. The plate’s gravitational attraction just about balanced the body force on us produced by the ship’s acceleration, leaving us in a comfortable and relaxing half-gee environment. The tidal forces caused by the gravity gradient were noticeable only if you looked for them. McAndrew’s vacuum drive worked flawlessly, as usual, tapping the zero point energy — “sucking the marrow out of spacetime,” as one of Mac’s colleagues put it.

“I don’t understand,” I’d once said to him. “It gets energy out of nothing.”

McAndrew looked at me reproachfully. “That’s what they used to say in 1910, when mad scientists thought you might get energy from the nucleus of an atom. Jeanie, I thought better of you.”

All right, I was squelched — but I didn’t understand the drive one bit better.

At the halfway mark we rotated the ship to begin deceleration and I cut the drive while we did it. Anna Griss had an opportunity to send her backlog of messages, and finally gave Will Bayes a few hours of peace. I was amused to see that her communications gave the impression that she was running everything on the Hoatzin. Her increased absence from Headquarters she attributed to delays on the trip. If the level of scientific expertise in the Food Department matched her own, she would probably get away with it.

For me, this should have been the best part of the mission, the reason I remain in space and never look for a Downside job. With the drive off we flew starward in perfect silence. I stayed by the port, watching the wheel of heaven as the ship turned.

The Hoatzin was within five percent of light-speed. As we performed our end-over-end maneuver, the colors of the starscape Doppler-shifted slowly from red to blue. I caught a last glimpse of Sol and its attendants before the massplate shielded them from view. Jupiter was visible through the optical telescope, a tiny point of light a fifth of a degree away from the Sun’s dazzling disk. Earth was gone. Its reflected photons had been lost on their hundred-and-fifty-billion mile outward journey.

I turned the telescope ahead, in a hopeless search for Manna. It was a speck in the star-sea, as far ahead of us as the Sun was behind. We would not detect its presence for another two weeks. I looked for it anyway. Then the shield came on to protect us from the sleet of hard radiation and particles caused by our light-chasing velocity. The stars blinked out. I could pay attention again to events inside the Hoatzin.

With little else to occupy her attention, Anna delegated her chores to Will Bayes and concentrated everything on charming McAndrew. Will and I received the disdain and the dog work. I sat on my anger and bided my time.

As for Mac, he had disappeared again inside his head. We had loaded a library of references on Lanhoff and the organic materials of the Halo into the computer before we left the Institute. He spent many hours absorbing that information and processing it in the curiously structured personal computer he carries inside his skull. I knew better than to interrupt him. After just a couple of futile attempts to divert him, Anna learned the same lesson. No doubt about it: she was quick. No scientist, but when it came to handling people she did instinctively what I had taken years to learn. Instead of social chit-chat, she studied the same data that McAndrew had been analyzing and asked him questions about it.

“I can see why there ought to be a lot of prebiotic organic stuff out in the Halo,” she said during one of our planned exercise sessions. She was dressed in a tight blue leotard and pedaling hard at the stationary cycle. “But I never did follow Lanhoff’s argument that there may be primitive life there, too. Surely the temperature’s far too cold.”

It was still the “Griss-Lanhoff” Theory for official records, but with us Anna had dropped her pretence of detailed knowledge of Lanhoff’s ideas. She had been the driving force to carry his ideas to practical evaluation. We all knew it; for the moment that was enough for her. I had no doubt that we would see another change when we arrived back in the Inner System.

McAndrew was idly lifting and lowering a weighted bar. He hated exercise, but he grudgingly went along with general USF orders for spaceborne personnel.

“It is cold in the Halo,” he said. “Just a few degrees above absolute zero, in most of the bodies. But it may not be too cold.”

“It’s much too cold for us.”

“Certainly. That’s Lanhoff’s point. We know only about the enzymes found on Earth. They allow chemical reactions to proceed in a certain temperature regime. Why shouldn’t there be other life-supporting enzymes that can operate at far lower temperatures?”

Anna stopped pedaling, and I paused in my toe-touching. “Even at the temperatures here in the Halo?” she said.

“I think so.” McAndrew paused in his leisurely bar-lifting. “Lanhoff argues that with plenty of complex organic molecules and with a hundred billion separate bodies available, a lot of things might develop in four billion years. He expected to find life somewhere out here — primitive life, probably, but recognizable to us. He was prepared to find it, and the Star Harvester was equipped to bring back samples.”

We dropped the subject there, but it went running on in my mind while Anna took McAndrew off to program an elaborate meal. I could hear her giggling from the next room, while visions of a Halo civilization ran wild through my brain. Life had appeared there, evolved to intelligence. The Halo society had been disturbed by the arrival of our exploring ship. Lanhoff was a prisoner. His ship had been destroyed. The Inner System and the Halo would go to war…

All complete rubbish. I knew that even as I fantasized, and McAndrew pointed out why when we discussed it later.

“We got the way we are, Jeanie, because life on Earth is one long fight for limited resources. Our bloody-mindedness all started out as food battles, three billion years ago. The Halo isn’t like that — everything will be part of the food supply. How much evolving would we have done if it rained soup every day and the mountains of Earth had been made of cheese? We’d still be single-celled organisms, happy as clams.”

It sounded plausible. McAndrew was so bright that you tended not to question him after a while. But an hour or two later I was worrying again. It occurred to me that Mac was a physicist — when it came to biology he was way outside his field. And something had happened to Lanhoff and his ship. What could it have been?

I didn’t mention it again, but I worried and fretted, while McAndrew and Anna Griss talked and laughed in the sleeping area and Will Bayes sat next to me in the control area, miserable with his own thoughts. He was so dominated by Anna that I often lost sight of him as an independent person when she was around. Now I found out what made him tick — security.

Poor Will. Looking for security he had joined the safest, most stable organization in Earth’s government: the Food Department. That was the place for a solid, Earthbound, risk-free job. He had no desire for adventure, no wish to travel more than a mile from his little apartment. He had been in space only once before, as part of a meeting between the Council and the United Space Federation. Now he was embarked on a mission so far from home that he might survive even if the Sun went nova.

How had it happened? He didn’t know. It didn’t occur to him to blame Anna. He sat about, uncertain and unhappy. I kept him company, my own worry bump throbbing randomly until at last it was time to throttle the drive and begin final search and rendezvous. Manna should be less than ten million kilometers ahead of us.

“QUERY DISTANCE FOR STAR HARVESTER APPROACH? DEFAULT VALUE: ZERO.”

Our computer began talking to us while we were still scanning ahead for first visual contact. No matter what had happened to the vessel’s crew, Star Harvester’s guidance and control system was still working. Automatic communication for identification and position-matching had begun between the two ships as soon as drive interference was low enough to permit signal transfer.

“Fifty thousand kilometers.” I didn’t want an immediate rendezvous. “Manual control.”

“FIFTY THOUSAND KILOMETERS. CONTROL TRANSFERRED.”

“We’ll see nothing from that distance.” Anna was impatiently watching the hi-mag viewing screen. “We’re wasting time. Take us in closer.”

We could now see the rough-cut oblong of Manna on the imaging radar. A bright cluster of point reflections at one end had to be the Star Harvester’s assembly of sections. I suddenly had a new feel for the size of the body we were approaching. Lanhoff’s ship was of the largest class in the USF fleet. Next to Manna it looked like specks of dust.

“Didn’t you hear me?” Anna spoke more loudly. “I don’t want a view from a million miles away — take us in closer. That’s an order.”

I turned to face her. “I think we should be cautious until we know what’s going on. We can do a lot of overall checking from this distance. It’s safer.”

“And it wastes time.” Her voice was impatient. “I’m the senior officer on this ship. Now, do as I say, and let’s get in closer.”

“Sorry.” I couldn’t delay this moment any longer. “You’re the senior officer while we’re in free flight, I agree. But when we’re in a rendezvous mode with another ship, the pilot automatically has senior decision authority. Check the manuals. I have final say on our movements until we’re on the way back to Earth.”

There was a long pause while we sat eyeball to eyeball. Anna’s face took on a touch of higher color on the cheeks. McAndrew and Will Bayes held an uncomfortable silence.

“You’ve had this in mind all along, haven’t you?” Anna said softly. Her voice was as cold as Charon. “Damn you, you counted on this. You’re going to waste everybody’s time while you play at being the boss.”

She went through to the other communications department, and I heard the rapid tapping of keys. I didn’t know if she was making an entry into the log, or merely calling out the section of the Manual that defines the transfer of authority to the pilot during approach and rendezvous. I didn’t care. Super-caution has always paid off for me in the past. Why change a winning hand, even for Anna Griss? I concentrated my attention on the incoming data streams.

Half an hour later Anna came back and sat down without speaking. I was uncomfortably aware of her critical attention over my shoulder. I gestured to the central display screen, where the second series of remotely sensed observations from Manna were now appearing. The computer automatically checked everything for anomalies. One new set was displayed in flashing red for our attention.

“That’s why I didn’t want to rush. I don’t think we’ve been wasting time at all. Mac, look at those radioactivity readings. What do you think of them?”

The computer had done its preliminary analysis, taking the ratio of radioactivity measurements from Manna to typical Halo bodies and to the general local background. McAndrew frowned at the smoothed values for a few seconds, then nodded.

“Uh-uh. They’re high. About six hundred times as big as I would expect.”

I took a deep breath. “So I think we know what happened to Lanhoff. One of the fusion units must have run wild when they were installing it. See now why I’m cautious, folks?”

Anna Griss looked stunned. “Then the crew all got a fatal overdose of radiation?”

“Looks like it.” I had proved my point, but not in a way that gave me any satisfaction. I felt sick inside. When a fusion plant blows, there’s no hope for the crew.

“No, Jeanie.” McAndrew was frowning and rubbing at his sandy hairline. “You’re jumping to conclusions. I said the radioactivity was six hundred times as big as it should be, and it is. But it’s still low — you could live in it for years, and it wouldn’t do you much harm. If a fusion plant had gone, the reading from Manna would be a hundred thousand times what we’re measuring.”

“But what else could give us abnormally high values?”

“I’ve no idea.” He looked at me apologetically. “And we’ll never know from this distance. Seems to me that Anna’s right. We may have to get in a lot closer for a good look if we really want to find out.”

Perhaps the idea that Lanhoff and his crew were almost certainly dead was hitting Anna hard for the first time. At any rate, there was no triumph in her expression as she watched me ease us gingerly forward until we were only ten thousand kilometers from the planetoid. We went slowly, all our sensor input channels wide open. I set the control system to hold us at a constant distance from the surface of Manna.

“That’s as far as I’m willing to take us,” I said. “We’re a long way from home, and I won’t risk our only way of getting back. Any closer look will have to be done with the transfer pod. Mac, I’ve not had time to watch the inputs. Is there anything about the ship or about Manna that’s looking out of line?”

He had been muttering to himself over by a display screen. Now he frowned and pressed a sequence of control keys.

“Maybe. While you were busy I did a complete data transfer from Star Harvester’s computer to ours. Lanhoff and his crew stopped feeding in new inputs a hundred and fifteen days ago — that’s when the signals to Oberon Station cut off — but the automatic sensors kept right on recording. See, here’s the very first radioactivity reading from Manna when they arrived, and there’s one taken just a few minutes ago. Look at ’em. Identical. And now look at this. This is the thermal profile of a cross-section through Manna’s center.”

A multi-colored blob filled the screen. It was a set of concentric ellipses, color coded to run from a dark red in its center portion to a violet on the outer boundary.

“Different colors represent different temperatures.” McAndrew touched a button, and a dark ellipse appeared around the red and orange portions at the center of the image. “I’ve just put in the contour for zero degrees Celsius. See? Significant, eh?”

“See what?” said Anna. She was sitting close to McAndrew, their shoulders touching.

“The inside — inside the curve. It’s warmer than the melting-point of ice. If Manna has a water-ice core, it must be liquid. There’s a couple of kilometers of frozen surface, then that liquid interior.”

“But we’re out in the Halo,” I protested. “We’re billions of miles from a source of heat. Unless — did Lanhoff already put one of his fusion plants in there?”

“No.” McAndrew shook his head. His eyes were sparkling. “The temperature distribution inside was like this before Lanhoff arrived. You’re right, Jeanie, it looks impossible — but there it is. Manna is three hundred degrees warmer than it has any right to be.”

There was a long silence. Finally Will Bayes cleared his throat. “All right, I’ll be the dummy. How can that happen?”

McAndrew gave a little bark of excitement. “Man, if I had a definite answer to that I wouldn’t hold out on you. But I can make a good guess. There has to be a natural internal source of heat, something like uranium or thorium deep inside. That’s consistent with the high radioactivity value, too.” He turned to me. “Jeanie, you have to get us over there, so we can take a good look at the inside.”

I hesitated. “Will it be safe?” I said at last. “If it’s uranium and water — you can make a nuclear reactor from them.”

“Yes — if you try really hard. But it wouldn’t happen in nature. Be reasonable, Jeanie.”

He was looking at me expectantly, while Anna sat silent. She liked to see him putting the pressure on me for a change.

I shook my head. “If you want to go over there and explore, I won’t try to stop you. But my job is the safety of this ship. I’m staying right here.” Logic was all on my side. But even as I spoke I felt that I was giving the coward’s answer.

From a distance of fifty kilometers, Manna already filled the sky ahead, a black bulk against the star field. Star Harvester hung as a cluster of glittering spheres near one end of the planetoid. It steadily grew in size on the screen as the pod moved in, one of its television cameras sending a crisp image back to my observing post on the Hoatzin. I could see the dozen Sections and the narrow connectors between them, hollow tubes that were flexible now but electromagnetically stiffened when the drive went on.

“Approaching outermost cargo sphere,” said McAndrew. I could see him on the screen that showed the inside of the pod, and a third image showed and recorded for me the pod control settings exactly as he saw them himself.

“Everything still appears perfectly normal,” he went on. “We’ll make our entry of Star Harvester through the Control Section. What is it, Anna?”

He turned to where she was monitoring another sensor, one for which I was not receiving coverage.

“Cut in Unit Four.” I said quickly.

At my command the computers sent the image Anna and Will were watching to fill the center screen. I saw a long shaft that extended from a cargo hold of Star Harvester and drove down to penetrate the rough surface of Manna. The camera tracked its length, switching to deep radar frequencies to generate an image where the shaft plunged below the planetoid’s surface.

“Is that a drilling shaft?” I asked. “It looks as though they were getting ready to put a fusion plant in the middle of Manna.”

“Wouldn’t make sense.” McAndrew spoke in an abstracted grunt, and I saw him rubbing at the balding spot on the back of his head. “Lanhoff knew quite well that Manna has a liquid core — he had the same computer base to look at as we do. With that core he didn’t need a fusion plant at all. The interior would be warm enough already for his enzymes to thrive.”

“Was he looking for radioactive material?” I asked; but I could answer that question myself. “It wouldn’t make sense. He could locate them the same way we did, from remote measurement. So why would he drill into the core?”

“I’ll tell you why,” said Anna suddenly. “That’s the way Arne always was. Anytime he saw something that he didn’t understand he wanted to investigate — he couldn’t resist it. I’ll bet he drilled to the core to take a closer look at something he’d detected in there — something he couldn’t examine closely enough from outside.”

The pod had been creeping in nearer and nearer to the hatches on the Control Section. I suddenly realized that once the three of them went inside I would be blind.

“Mac, as soon as you get in there, turn on all the monitors and tell the computer to send the signals back to me here on the Hoatzin.” I raised my voice. “And one of you has to stay in the Control Section if you go down to the surface. D’you hear me?”

He nodded vaguely, but he was already moving toward the hatch. Anna followed him. The last thing I saw before the camera could no longer keep them in view was Will Bayes’ face as he turned to take a last worried look around the pod.

Deserted, but in perfect working order; that was the conclusion after a thorough examination of the Control Section of Star Harvester.

I had followed on the remote monitors as the other three made their inspection, step by step, and I could not fault them for lack of caution.

“We’ll not find Lanhoff and his crew here,” said McAndrew finally, when they were back in the main control room. “They must have gone down into the interior of Manna. Look at this.”

A computer-generated profile of the shaft leading down from the ship to the surface appeared on the screen in front of me. It penetrated the frozen outer crust and terminated in an airlock leading to the liquid core. In the graphics display the broad shaft looked like a hair-thin needle piercing an egg. I was astonished again by the size of the planetoid. Its liquid core held half a million cubic kilometers of liquid. Maybe we would never find Lanhoff and the other crew members.

“We know they went down there,” went on McAndrew, as though he was reading my thoughts. He held up a big clear container full of a cloudy yellow fluid. “See? They brought back samples. I’ll send you the analysis, but I can tell you now that the results are just what Lanhoff predicted.”

“It’s high-level organic materials,” added Anna. She was looking at me in triumph. “I told you we had to come here to find anything useful. This is just as we expected, but even more concentrated than I hoped. We’ve found a mother lode. The whole inside of Manna is like a rich soup — one of us could probably drink it for dinner and feel well-fed.”

Will Bayes was staring at it dubiously, as though he expected Anna to tell him to go ahead and take a swig. “There’s things living in it,” he said.

My old fears came running back. “Mac, be careful how you handle that. If there are organisms there…”

“Just single-celled ones.” McAndrew was excited. “Lanhoff thought he might find primitive life here, and he was quite right.”

“And it’s DNA-based,” added Anna. “The same as we are.”

I looked more closely at the yellow broth. “So the old theories must be right? Life came to Earth from outside.”

“That’s the real significance of what they found on Manna,” said McAndrew. “Life didn’t originate on Earth. It began out here in the Halo, or somewhere even farther out, and drifted in to Earth — maybe in the head of a comet, or as smaller meteorites. But see the difference; down on Earth we’ve had pressures to make us evolve away from a single cell form. Here, there’s heat from the radioactive materials in the middle of the planetoid, and there’s food galore. There’s no reason for evolution as we know it. That’s why I don’t share your worries, Jeanie, about going down to the interior. There’s no evolutionary reason for predators on Manna. We won’t find sharks and tigers here. It’s the Garden of Eden.”

Anna nodded her agreement and squeezed his arm. They were both so excited, I wondered if I were the irrational one. The more enthusiastic they became, the more uneasy I felt. No sharks and tigers, maybe — but wouldn’t there still be natural selection, even if it went on very slowly?

Shades of Malthusian Doctrine: the number of organisms would follow an increasing geometric progression, and the food resources were finite. Eventually there would have to be a balance, a steady state where dying organisms were just replaced by new ones; and then natural selection ought to take over, with competition between different forms. I didn’t have that logic explicitly in mind, all I knew was that something seemed wrong. And I knew that Mac was no biologist. I stared at the screen and shook my head.

“So what happened to Lanhoff and his crew?” I said.

There was a long, uneasy silence.

“Quite right, Jeanie,” said McAndrew at last. “We still have no answer to that. But we’re going to find one. Will can stay here, and Anna and I will go down there now.”

“No.” My pulse began to race. “I won’t allow it. It’s too dangerous.”

“We don’t agree,” said Anna softly. “You heard McAndrew, he says we should look down there — and we’ll go in our suits, so we’ll be well protected.”

Fools rush in where angels fear to tread. Anna Griss knew how to survive in an Earthbound bureaucratic free-for-all, but she was a long way from her home ground. And if she was relying on Mac’s instincts to save their skins…

“No.” My voice cracked. “Didn’t you hear me? I absolutely forbid it. That’s an order.”

“Is it?” Anna didn’t raise her voice. “But you see, we’re not in the spacecraft rendezvous mode now, Captain Roker. The Star Harvester is tethered to the planetoid. That means I command here, not you.” She turned to McAndrew. “Come on, let’s make sure we’re fully prepared. We don’t want to take any risks.”

Before I could speak again she reached forward to the monitor. I suddenly found that I was looking into a blank screen.

It took me a long five minutes to patch in a substitute communications link between the computers of the Hoatzin and the Star Harvester.

When the auxiliary screen came alive I saw Will Bayes fiddling with the control bank.

“Where are they, Will?”

He turned quickly. “They’re on the way down to the surface. Jeanie, I couldn’t stop them. I said they shouldn’t go, but Anna wouldn’t take any notice of me. And she has Mac convinced, too.”

I knew McAndrew — he hadn’t taken any convincing at all. Show him an interesting intellectual problem, and preservation of life and limb came a poor second to curiosity.

“Don’t worry about that, Will. Link me to the computer on board the transfer pod.”

“What are you going to do?”

“Go after them. Maybe Mac is right, and they’ll be fine, and in no danger. But I want to be the rearguard and trail along behind them, just in case.”

Will could have probably flown the pod to pick me up in an emergency, and I knew that the computer could have done it with a single rendezvous command from me. But Will and the computer would have followed the book on permissible rates of acceleration and docking distances. I took remote control of the pod myself, overrode the computer, broke every rule in the manual, and had the pod docked at the Hoatzin in less than fifteen minutes. Going back to the Star Harvester we beat that time by a hundred seconds.

Will was waiting at the main lock with his suit on. “Something has gone wrong,” he said. “They told me they would send a signal every ten minutes, but it’s been over twenty since the last one. I was going to go down and see what’s happening.”

“Did you see any weapons on board when you were looking over the ship earlier?”

“Weapons?” Will frowned. “No. Lanhoff had no reason to carry anything like that. Wait a minute, though, what about a construction laser? That can be pretty dangerous, and there are plenty of those in Section Six.”

“Get one.” I was preparing the transfer pod for a rapid departure from Star Harvester if we needed it. One time in a thousand, a precaution like that pays off.

“I’ll get two.”

Will was off along the tube between the Sections before I could argue with him. I didn’t want him with me in the middle of Manna — I wanted him available to help me out if I ran into trouble myself.

What was I expecting? I had no idea, but I felt a lot better when I had my suit firmly closed and a portable construction laser tucked under one arm. Will and I went together to the entrance of the long tunnel that led down to the interior of Manna.

“Right. No farther for you.” I looked at the peculiar way he was holding the laser, and wondered what would happen if he had to use it. “You stay here, at the head of the shaft. I’ll send you a signal every ten minutes.”

“That’s what Anna said.” His words echoed after me as I dropped away down the broad shaft.

The illumination came only from the light on my suit. Seen from the inside, the shaft out of the cargo hold dropped away in front of me like a dark, endless tunnel. Manna’s gravity was negligible, so there were none of the Earth dangers of an accelerated fall. But I had to take care to remain clear of the side of the tunnel — it narrowed as we went deeper into the planetoid’s crust. I drifted out to the center of the shaft, turned on the coupling between the suit’s conducting circuits and the pulsed field in the tunnel wall, and made a swift, noiseless descent.

The three kilometer downward swoop took less than a minute. All the way to the airlock at the bottom I watched carefully for any sign that McAndrew and Anna had met trouble there. Everything was normal.

The drilling mechanism at the end of the shaft was still in position. Normally the shaft could extend itself through hard, frozen ice at a hundred feet an hour. When they came to the liquid interior, however, Lanhoff had arrested the progress of the drill and installed the airlock. It was a cylindrical double chamber about six meters across, with a movable metal wall separating the two halves.

I cycled through the first part of the lock, closed the wall, and went forward to the second barrier. I hesitated in front of it. The wall was damp with a viscous fluid. The airlock had been used recently. Anna and McAndrew had passed through here to the liquid core of the planetoid. If I wished to find them I must do the same.

Was there a port? I wanted to take a good look at the interior of Manna before I was willing even to consider going through into it.

The only transparent area was a tiny section a few inches across, where a small panel had been removed and replaced by a thin sheet of clear plastic. Lanhoff must have arranged it this way, to make an observation point before he would risk a venture beyond the lock. Despite his curiosity referred to by Anna, it suggested that he was a cautious man — and it seemed to increase the odds against me. I was diving blind, and in a hurry.

I drifted across and put the faceplate of my suit flat against the transparent plate. The only illumination in the interior was coming from my suit, and because it had to shine through the port I was confused by back-scattered light. I held my hand to shield my eyes, and peered in.

My first impression was of a snowstorm. Great drifting white flakes swam lazily across the field of view. As I adjusted to the odd lighting, the objects resolved themselves to white, feathery snowballs, ranging in size from a grape to a closed fist. The outer parts were in constant vibration, providing a soft-edged, uncertain shimmer as they moved through the pale yellow fluid of Manna’s interior.

Even as I watched, the number and density of the white objects was increasing. The snowfall became a blizzard. And floating far away from me, almost at the limit of vision, I saw two great white shapes. They were travesties of the human form, bloated and blurred outlines like giant snowmen. Every second they grew bigger, as more and more snowballs approached and adhered to their surfaces. They were swelling steadily, rounding to become perfect spheres.

I shivered in my suit. Alien. The figures looked totally alien, but I knew what I had found. At their centers, unable to see, move, or send messages, were McAndrew and Anna. As I watched I thought of the guardian white corpuscles in my own blood-stream. The feathery balls were like them, busy leukocytes crowding around to engulf and destroy the foreign organisms that dared to invade the body of Manna.

How could I rescue them? They were in no danger for the first few minutes, but the snowballs would muffle the escape of heat from the suits. Unless the clinging balls were cleared away, Anna and McAndrew would soon die a blind and stifling death.

My first instinct was to open the lock and plunge through to the interior. Another look at the feathery snowballs changed my mind about that. They were thicker than ever, drifting up from the deep interior of the planetoid. If I went out there they would have me covered in less than a minute. The laser that I had brought with me was useless. If I used it in water, it would waste its energy turning a small volume close to me to steam.

And I had no other weapon with me.

Return to the Star Harvester, and look for inspiration there? It might be too late for McAndrew and Anna.

I went across to the side of the lock. There was a dual set of controls for the drilling shaft there, installed so that drilling progress could be monitored and modified on the spot. If I started the drill, the fluid ahead would offer little resistance. The tunnel would extend further into the liquid, far enough to enclose the area where the two misshapen spheres were floating. So if I opened the lock first, then activated the drill…

The timing would be crucial. Once the lock was open, liquid would be drawn into the evacuated area around me. Then I would have to operate the drill unit so that the open lock moved to enclose the two swollen masses of snowballs, close the lock again, and pump the liquid out. But if I was too slow, the blizzard of snow would close in on me, too, and I would be as helpless as McAndrew and Anna.

Delay wouldn’t help. I pressed the lever that opened the lock, moved to the side of the chamber, and started the drill extender.

Liquid rushed in through the opening aperture. I struggled to move forward against its pressure, fighting my way back to the lock control.

There was a swirling tide of white all around me. Feathered balls hit my suit and stuck to it, coating the faceplate in an opaque layer. Within thirty seconds I could not see anything, and my arms and legs were sluggish in their movements as I clung to the lock lever.

I had not anticipated that I would become blind so quickly. Were McAndrew and Anna already swept into the chamber by the advancing drill and the opened lock? I had no way of knowing. I waited as long as I dared, then heaved at the lever. My arm moved slowly, hampered by the mass of snow-spheres clinging to it. I felt the control close, and sensed the muffled roar of the pump. I tried to thrash my arms, to shake off the layers that clogged their movement. It was useless. Soon I was unable to move at all. I was in darkness. If the snowballs could tolerate vacuum, McAndrew and Anna and I would go the same way as Lanhoff; we’d be trapped inside our suits, our communication units useless, until the heat built up to kill us.

It was a long, long wait (only ten minutes, according to the communications link on board the ship — it felt like days). Suddenly there was a lightening of the darkness in front of my faceplate. I could move my arms again. The feather balls were falling off me and being pumped out through the airlock.

I turned around, peering through the one clear spot on my faceplate. There were two spherical blobs with me in the chamber, and they were gradually taking on human shapes. After another five minutes I could see parts of their suits.

“Anna! Mac! Turn around.”

They clumsily rotated to face me. I saw them staring out of the faceplates, white-faced but undeniably alive.

“Come on. Let’s get out of here.”

“Wait.” McAndrew was taking a bag from the side of his suit, opening it, and scooping up samples of liquid and snowballs. I decided that he was terminally crazy.

“Don’t fool with that, Mac — let’s get out of here.”

What was the danger now? I didn’t know, and I wasn’t going to wait to find out. I reached out, grabbed his arm, and began to haul him back through to the other chamber. We were still sloshing in a chaos of fluid and floating feather balls.

Anna grabbed at my arm, so I was towing both of them. I could hear her teeth chattering.

“God,” she said. “I thought we were dead. I knew it, it was just like being dead, no sound, nothing to see, not able to move.”

“I know the feeling,” I grunted — they were a weighty pair. “How did you get caught? I mean, why didn’t you get back into the airlock as soon as the snowballs arrived?”

We were scooting back up the tunnel as fast as we could, McAndrew still clinging to his bucket of specimens.

“We didn’t see any danger.” Anna was gradually getting control of herself, and her grip on my arm had loosened. “When we first came through the lock there were maybe half a dozen of those fuzzballs in sight. McAndrew said we ought to get a specimen before we left, because they were a more complex life-form than any that Lanhoff had reported. And then they started to arrive in millions, from all directions. Our suits were covered before we could get away — we didn’t have a chance.”

“But what are they — and what were they doing?” I said.

We had reached the top of the tunnel and entered the cargo sphere. There was no sign of Will Bayes — it occurred to me that I hadn’t sent him a single signal of any kind since I left. He must be frantic. I hit the switch that would fill the chamber with air. For some reason I was keener to get out of that suit than I had ever been.

McAndrew placed his container on the floor and we all began to work our way free, starting with the helmets.

“What were they doing? Now that’s a good question,” he said. “While we were stuck in the middle of them down there, I had time to give it some thought.”

Well, that sounded right. When McAndrew stops thinking, he’ll be dead.

“Lanhoff and I made a big goof,” he went on, “and for him it was a fatal one. We both argued that the food supply here was so plentiful that there’d be no pressure to evolve. But we forgot a basic fact. An organism needs more than food to survive.”

“What else? You mean moisture?” I had my suit off, and air had never tasted so good.

“Moisture, sure. But as well as that it needs warmth. Here on Manna, the evolutionary pressure is to get near a heat source. If you’re out too far from the center, you become part of the frozen outer layer. Those snowballs normally live down near the middle, getting as close as they can to the radioactive fragments that provide the warmth.”

Anna was out of her suit. Now that we were safe, she was making a tremendous effort to gain her self-possession, Her shivering had stopped and she was even patting at her damp and tangled hair. She peered curiously down at the container of feathered snowballs. They were still moving slowly around in the yellow liquid.

“The radioactivity must speed up their rate of evolution, too,” she said. “And I was thinking they wanted to eat us.”

“I doubt that we’re very appetizing, compared with their free soup,” said McAndrew. “No, if there hadn’t been so many of them they’d have been harmless enough. But when we came along, they sensed the heat given off by our suits, and they tried to cuddle up to us. They didn’t want to eat us, all they were after was a place by the fireside.”

Anna nodded. “This is going to create a sensation when we get back to Earth. We’ll have to take a lot of specimens back with us.”

She was reaching down towards the open container. One of the snowballs had fully opened and was a delicate white mass of feathery cilia. She put out her forefinger as though she intended to touch it.

“Don’t do that!” I shouted.

Maybe she was not even considering any such thing, but my loud command made her stiffen. She looked up at me angrily.

“You saved us, Captain Roker, and I appreciate that. But don’t forget who is in charge of this expedition. And don’t try to order me around — ever.”

“Don’t be a fool,” I said. “I wasn’t ordering you around — I was speaking for your own good. Don’t you have any idea what might be dangerous?”

My own tone must have betrayed my impatience and anger. Anna stiffened, and her color went from white to red.

“McAndrew has pointed out that these lifeforms would have been quite harmless if there had not been so many of them,” she said. And then she reached forward into the container and deliberately touched the expanded snowball with her forefinger. She looked up at me. “Satisfied? They’re perfectly harmless.”

Then she screamed. The ball was clinging to her finger as she withdrew it, and the cilia had enveloped it as far as the second joint.

“It won’t come off!” She began shaking her hand desperately. “It hurts.”

I swung my helmet hard at her finger, and the edge caught the ball near its middle. It was jarred loose and flew across the chamber. Anna stood and looked ruefully at her hand. The finger was reddened and swollen.

“Damnation. It stings like hell.” She turned accusingly to McAndrew and held forward her injured hand. “You fool. You told me they’re harmless, and now look at my finger. This is your fault.”

We all stared at her hand. The swelling on her forefinger seemed to be getting bigger and redder.

McAndrew had been standing there with a startled and perplexed expression on his face. Before I could stop him he picked up the laser that I had laid on the floor, aimed it at Anna, and pressed the switch. There was a crackle from the wall behind Anna, and the smoke of burned tissue. Her arm had been neatly severed above the elbow, and the wound cauterized with a single sweep of the instrument.

Anna looked at the stump with bulging eyes, groaned, and started to fall sideways to the floor.

“Mac!” I grabbed for the laser. “What the hell are you doing?”

His face was pale. “Come on,” he said. “Let’s get her to the robodoc. This isn’t too serious — she’ll have to wait to regenerate it until we get home and find a biofeedback machine, but we can’t help that.”

“But why did you do it?”

“I made one bad mistake, back there outside the air lock,” We were hurrying back through the ship, supporting Anna between us.

“I don’t want to make another one,” he went on. “Lanhoff’s notes on the single-celled organisms inside Manna pointed out that they didn’t have a sexual method of reproduction, but they have something that resembles the plasmids down on Earth — they swap sections of DNA with each other, to get the mixing of offspring characteristics. I wondered about that when I read it, because it suggests a mechanism for speeding up an evolutionary process. But I skipped on past it, because I was so sure there would be no evolutionary pressures at work inside Manna.”

We were almost at the Control Section of Star Harvester. Unless Will had gone mad and flown off in the transfer pod, we were only twenty minutes away from the Hoatzin’s robodoc. Anna was coming out of her faint, and groaning a little.

“Mac, I still don’t see it. Why does the evolution method of the creatures inside Manna mean you had to burn off Anna’s arm?”

“If they do swap tissue regularly, their immune reaction systems have to recognize and tolerate the exchange. But we’re not made like that — Anna’s immune reaction system might mop up the materials that the snowball transferred to her bloodstream, but more likely the stuff would have killed her. I daren’t take the chance.”

We had come to the hatch that led to the transfer pod. Will Bayes stood there. For a fraction of a second he looked relieved, then he took in the whole scene. We were all pale and panting. I was dragging Anna along while she lay in a near-faint with only a stump of a right arm; and McAndrew, wild-eyed and lunatic, was bounding along behind us, still brandishing the laser.

Will backed away in horror, his hands held in front of him. “Come on, man, don’t just stand there,” said McAndrew. “Get out of the way. We’ve got to get Anna over to our ship and let the doc have a go at her. The sooner the better.”

Will took a hesitant step to one side. “She’s not dead, then?”

“Of course she’s not dead — she’ll be good as new once she’s been through a regeneration treatment. We’ll have to keep her sedated for the trip back, but she’ll be all right.”

I went to the controls of the pod, ready to take us back to the Hoatzin. It hadn’t occurred to me that Anna would be quieted down now for the return trip, but I wouldn’t be the one to complain.

“You mean we’re actually going home?” asked Will. His tone suggested that he had never expected to see Earth again.

“Just for a while.” McAndrew had settled Anna as comfortably as he could, and now he was looking disconsolately around him for the bucket of lifeform samples that we had left behind in the Control Section of Star Harvester.

“We’ll be back, Will, don’t you worry,” he said. “Anna was quite right: when Lanhoff found Manna he stumbled across a real treasure trove. We’ve hardly scratched the surface. As soon as we can get organized, there’ll be another party from the Food Department. And I’m sure we’ll all be here with it.”

My attention was mainly on the controls, so I’m not sure that I heard Will’s low mumble correctly. But I think he was saying something about a transfer to the Energy Department.