Far Frontiers Part 2

"We're a.s.signed to evaluate the equipment. I can't recommend one piece of equipment over another if there isn't a fair test."

Tom left. Alone with my own thoughts, my mind wandered to my conversation with Nichols. I had lied to hnn; I still considered Martin my husband. If the Theological Council found out-I tried to push Martin from my mind. I had my job, and right now that needed my attention.

I kept working while waiting for my technician's reappearance. Tom wasn't returning. I could feel the tension creeping up my anns and residing in my neck as I sliced sections off the rock. Where was that man? And more importantly, what was he doing? He finally came back looking as if he had only been gone the five minutes the job should have taken instead of thirty.

He could have done most of the thin sections himself.

"You checked on your report, I a.s.sume?" I asked.

"No, I got a personal call." He avoided looking me in the eye-a bad sign.

"We're on a tight schedule. I'd appreciate your keeping your mind on your duties."

For a moment Tom looked like he was going to justify his actions, make up some excuse; instead he answered, "Yes, ma'am."

Perhaps he was reporting my old-fashioned ways- my insistence that "real" thin sections be made, as if I didn't trust the scanners. I didn't. Scanners had a place in the lab. They could accurately give mineral content-quartz, more k-spar than plag, some muscovite-the answer had to be a granite, or was it a rhycute? The day a scanner could consistently distinguish between rhyolite and granite, would be the day I- It'd never happen on my watch.

Only a few minutes more pa.s.sed before a soft buzzer interrupted us. It was Carrie's signal telling us the samples were ready. By the time Tom returned, I had cut ten centimeters into the rock. I stopped, climbed down the ladder, and waited as Tom inserted a thin section into the microscope and displayed the sample's image on the half-meter-square view screen.

What had been grains too fine to see with the naked eye were now pale green to clear fibrous crystals cutting through and surrounding colorless orthorhombic crystals. I set the torch down and turned the scope's stage, rotating the picture on the screen. I put in the polarizing lens and turned the stage again, then removed the lens. I moved the thin section around, examining the entire sample."I don't know that one, Doctor," Tom said as he pointed to the screen.

"It's divine altering to chiysotile asbestos. Serpentine. And I'd have to bet that there wasn't a metamorphic rock within a thousand klicks of that site."

Tom shrugged. "Maybe a storm surge washed that hunk up on the beach or a shoal during or just before the last eruption."

"Have to wait until we've time to examine the geophysical logs from the sea floor to find a source rock. The seismic profiles should scream out the change from oceanic basalt to a serpentine." Now if the data hadn't been lost, I wanted to say, but didn't. I moved the slide around again, bothered by what I saw. "This is why visual inspection is useful, Tom. A probe would indicate serpentine and leave it at that." Given enough time, I might turn even Tom into a decent technician. Might. "This doesn't show the usual macroscopic fibers of natural chrysotile. The fabric is uniformly amorphous, an igneous texture, yet the mineralogy says metamorphic."

"Maybe we should cut deeper, beyond the worst heating effects from the molten lava?"

"My thoughts exactly. Let's cut off this corner we've been working on."

With laser in hand, I adjusted the beam. At the top of the rock I started a cut about thirty centimeters from the outer edge and moved down about thirty centimeters and over to the other edge. The laser encountered varying densities of rock, slowing the process as I adjusted the beam several times. As we lifted the severed corner away, something fell to the floor with a solid thump. I stared openmouthed at several chunks of red granite; other pieces lay inside a cavity in the original rock.

"Mother of Heaven!" Tom said.

I squelched my excitement, and practically dropped the corner piece into Tom's grasp, then retrieved the closest piece of granite from within what I now saw was an asbestos sh.e.l.l. I turned the granite over in my hands, then felt the inner surface of the asbestos rock.

"Now how in Heaven's name can this be?" I tried to ~ sound confused, and found it wasn't too hard as a gnawing began in my stomach. Tom would report my every word.

Scowling, I got down from the ladder, walked around the rock again and picked at a small chunk of lava that stubbornly clung to the outer surface of the lighter-colored rock. Dry salt from the ocean still coated the rock, adding a rich smell to the ship's filtered air.

"Granite pieces inside a hollow piece of asbestos!" I shook my head in a scholarlyfashion. "Geologically impossible."

Tom picked up another piece of granite from the floor. "Asbestos can be made into different objects, right?"

"Sure," I agreed. "It was used extensively in the past by weaving the fibers, much as you'd weave cotton. It was also made into a type of felt."

"Paper. wasps use wood to build their nests. Could these proto-trilobites use asbestos in their nesting?"

I looked at the slide still in the scope. "Inventive, Tom." And meant it. "Theologically sound." Another good point in his favor. "I can't think of a better explanation. It'll make Nichols happy." Tom didn't notice my sarcasm. "There's a problem in that there is no Life on this planet anywhere near as advanced as wasps. Also why put granite inside?"

Tom shrugged. 'Their own eggs were destroyed or they just liked pretty rocks? I mean, look at this. Fresh, unweathered red, feldspar crystals and silver mica, some pyrite." He moved the sample in the lab's bright light. "Look how it sparkles. Anyone would like this, even Commander Nichols."

I restrained my comments, tossed my rock sample into the air and caught it again. "An age curve would tell us how long ago the lava encased it. The heat should have penetrated even this thickness of asbestos and changed the lead values from their base." I indicated the rock he was holding. "Have Carrie get me a ratio curve."

"Yes, ma'am."

I fished around in my coverall pocket for a hand lens and looked at the granite sample more closely. "Tell her to tly zircon, then a sphene separation for dating; both minerals are present in high enough quant.i.ties. That'll give us a cross-check. I want to know how long it's been since that lava flow's heat changed the time curves. Then we'll compare that with the actual pota.s.sium-argon date from the lava flow."

The graph glowed on the computer screen. The lead 206-uranium 238 age ratio was plotted against the lead 207-uranium 235 age ratio. In a perfectly closed system the two age ratios would be equaland the rock's correct age would lie on the concordia-the curved line that gently arced across the screen. But nothing was a closed system and, as I expected, the lava encasing the asbestos and its enclosed granite had caused a thermal resetting of the granite's lead-uranium ratio. Its age now plotted below the concordia curve, on the straight line: the discordia. I stared hard at the graph.

The lava had encased this asbestos rock for some 8,000 years. I engaged the intercom.

"Astronomy Department, Greely here."

I got the old man himself. He must be bored. "Dr. Greely, this is Dr. Sehkar. I've some rocks that I'm trymg to date. Do you have the primeval lead ratio from this system's asteroids yet?"

"This about your new monolith?"

"W'hat?"

"Between Nichols and Tom, the whole ship has heard about your new rock."

'Thanks for the warning," I replied dryly. "You'd think they'd have better things to do than talk about my work habits. As if no one has ever collected a rock before!"

The older man laughed briefly. "You tend to bring bigger samples home and more of them than most researchers. People notice and, sometimes, are even infected with your pa.s.sion for rocks."

"Yeah, right."

"It'll take only a minute to get the lead ratios for you.

I waited in silence, staring at the graph, trying to get it to answer my rising number of questions.

Greely's voice broke my concentration. "I've attached a file of values for you to your home directory. As expected, this planetary cloud had a compositional makeup very similar to Earth's. We've found an absolute age of two-point-four times ten-to-the-ninth years with the standard error deviation."

A chill crawled down my spine. "Are you sure?"

"Yes. In fact, you could use Earth standard ratios for lead isotopes, and I suspect for uranium and strontium too, and still be accurate within an acceptable error band. As accurate as you can get with this data set, anyway. Why? You sound troubled."

I sighed. Where did I begin? "I am. We ran some tests on a granite found inside my monolith. I plugged the ratios with Earth's values, expecting that that would suffice, but I goteight times ten-to-the-ninth years."

'Three times too old! That's some error. You use zircon?"

"Zircon and sphene. Both methods produced the same age. And the pota.s.sium-argon date for an encasing lava flow matches the discordia curve of the granite. What does the solar spectrum say about this system's sun?"

"Let me recheck my values. I'll get back to you."

I waited and reran the numbers through the model. It wasn't long before the intercom sounded.

Greely sounded younger with his enthusiasm. "Dr. Sehkar, I reevaluated this star's spectrum. For a G6, this sun's at the early stages of main sequence. If it were eight billion years old, the spectrum would show a buildup of heavy elements. I don't see that. This sun's just beginning to live. It's nowhere near the helium burning sequence."

"Which means I've got a significant error somewhere. These samples look fresh enough, as if they were taken from the middle of a pegmat.i.te, not some-thing found at the surface, or in a lava field. It's hard to believe these rocks are even half their age."

"I can't think of many answers, and none the theologians would like."

"Ouch, how you talk, and over an open channel! There must be an error, somewhere."

Knowing I wasn't convincing either Greely or myself.

"G.o.d will provide the answer." That was better language. "I'd say someone was pulling your leg and gave you a bogus sample, except the oldest system any of our ships have been to is Kapteyn's star and its dinosaur planet. That's only six-point-two billion years old."

"I wouldn't call Kapteyn's fauna dinosaurs," I said patiently.

"You geologists are too fussy, as bad as theologians. Warm-blooded lizards are dinosaurs!

I don't care about their hip joints."

"I bow to popular consensus, Doctor. I'll just have to check my equipment. If you find any errors ...

"I'll call. Greely out."

I returned to the monolith to empty the interior samples into a storage bin. My hand shook slightly. I was glad to be alone. All the rock samples were near fist-size, each had rough sides, and sported lighter-colored marks. Other rocks bore recent scars from my cold-laser knife. The bulk of the samples were red granites with some grays. There were a few basalts and garnetschists. The monolith's chamber was small, about one-third of the overall size, with the bottom being a smooth serpentine layer. I ran a handheld penetrating radar down the monolith's side. It showed varying densities in the rock, but in a regular pattern. I'd bet there were a total of three distinct chambers! The other two would be just like this one at the top. I set up a suction-mounted laser drill in the middle-third of the monolith, and attached an airtight shield over it with monitoring devices.

It took the drill only a few minutes to punch a small hole into the asbestos side. The inner gases were composed of oxygen, with small amounts of argon, neon, nitrogen-breathable air, but dead air, no microbes- nothing like the atmosphere existing on Delta Pavonis Two now, or anytime in the past. I repeated the process on what I suspected would be the lowest of three seg- ments. Same air chemistry. Both gas samples would be saved for climatology. Maybe Greely knew someone from that department who could do a detailed a.n.a.lysis without talking too much.

With the laser, I enlarged the middle hole and found numerous fossiliferous carbonates and marbles, and kimberlites.

"d.a.m.n, the find of a-d.a.m.n," I muttered. I had to have a plan before Nichols showed up.

Was I just that lucky, or were finds of this nature so commonplace that other scientists ignored them out of self-preservation? Had to be, but I had never even heard a single rumor!

Angshu!

Nichols would start with rumors about signs of intelligent life and then try to trap me in heresy charges. No, I was smarter than that, wasn't I?

I adjusted the laser beam and moved down to the lowest portion of the rock and sliced off the lava still clinging to the main rock. I cut a round hole some twenty centimeters in diameter through the serpentine sides; its thickness matched above. A spot glance at the interior's contents indicated several varieties of sandstones, conglomerates, and quartzites.

I returned to the second chamber to remove the contents, and found I was examining a fossiliferous carbonate. No, I would examine everything further between planetfalls, when I had time; right now, the sooner they disappeared into cabinets, the better. Keep Tom busy elsewhere.

Still, as I carefully placed each sample into a storage bin, I identified them, trying to determine where on this watery planet I could find the outcrop. I stopped unloading when I found a piece of black slate. I turned it over and found a perfectly preserved trilobite the size of my thumb. If I were in graduate school, I'd call it a Cambrian Ogygopsis. How would an XO theologian explainsuch a similar species on so young a planet-only 2.4 billion years old! It had taken Earth nearly 4 billion years to produce such a species.

They'd find a way.

I gently wrapped it in protective padding. Every subtle detail of that fossil was important; I dare not chance another rock damaging it now.

Next I found a pure white, finely crystalline marble. Light danced off the crystal faces as I turned the piece. I caught my breath. The marble contained a fossil of a jellyfish-like creature twelve centimeters long and five centimeters wide. Under the bulbous upper portion extended three tentacles that terminated into claws. The soft tissue was wonderfully preserved!

Tingling ran from my toes to my scalp. I rushed into my office and knelt by my private rock collection- still decorating the floor. I sorted rocks until I found a specific light gray marble; the fossil consisted of two tentacled claws, below which was, perhaps, a rounded sh.e.l.l. I held the pieces side-by-side. My private specimen's fossil was incomplete, but both fossilized creatures were the same species in the same type of rock, probably from the same rock formation.

I had colected my sample from a ma.s.sive asteroid belt circling Ophiuchi 36-many light-years away from this small planet we now orbited.

The vision of Ophiuchi's tn-suns swam in my thoughts, as I had last seen them, each an orange-yellow globe in the black velvet of s.p.a.ce, ringed- even as Saturn was, but on an infinitely larger scale-by two halos of rubble.

The only planets that had orbited the K-type, trinary star system had broken up some 5,000 years ago. Now each ring was slowly coalescing into another, smaller planet. The inner debris uniformly showed that the original planet had once been thriving with life. That planetary system had begun the changes in my life. But it hadn't been till the next planetfall that my famil- iar life would be forever lost because of a planet which orbited a sun too small to even show up on my greatgrandmother's star charts. Ophiuchi BD-12 had sent my husband to jail and me into virtual exile from the heart of science and the Explorer Program into the backwater of the Survey Program. The JFK had been the Science Council's shining star, the Chamberlin's was old and past prime.

How could things have been handled differently? How should we have handled it better?

Could I have changed things? Time slipped away as I daydreamed.A waste! The past could never be recaptured. My gaze strayed back to the jumble of rocks still on my floor.

"Well, this is one problem I can fix." I reached over and buzzed Angshu's school.

"Child care," Betty Saari said.

This woman always sounded chipper and on top of any situation-no mountain too high, no storm too dangerous. "Betty, this is Somita Sehkar. How's Angshu behaving himself?"

"h.e.l.lo, Doctor. He's been an angel, as always." There was mirth in Betty's voice that caused me to chuckle, wondering what my son had been up to this time.

"Earlier he was a bit more mischievous and as a result my office needs straightening before we leave orbit. Is there a sitter available to bring him here and supervise him while I finish my report?"

"I've got a twelve-year-old boy I can spare. Will he do?"

"Perfectly."

'They're eating at the moment. I'll send them over after they've finished."

"Great! Thank you."

"My pleasure!"

I cut the comm link and again knelt by the rock pile. With a brief snap, the first disarrayed shelf was back in its operational mode. One shelf followed after another. I was about to snap the last collapsed shelf into place when I froze. Ophiuchi 36's tn-suns swam before my mind's eyes.

My gaze moved ever so slightly to rest on the rocks at my knees. A limestone on top of the pile still had the lighter colored percussion marks on one edge where my hammer had struck the rock to break it into a smaller sample.

I saw again the samples from within the monolith. Many of the granite pieces contained such marks- crushed crystals, almost white against the darker colored minerals. Of course I hadn't paid attention before now! One never sees the common, everyday things. But the rocks from within the monolith weren't supposed to be hand samples. Not for me anyway; not for the Theological Science Council on Intelligent Life.

The answer was so simple and splendidly clear. Two rock hounds, eight thousand years apart!

How were we different? What had the other- The intercom's soft chime interrupted me.

"Sehkar here."'This is Ops, Dr. Sehkar. You haven't answered our request for clearance to leave orbit in two hours. Is your department all clear?"

I toggled the computer and found several calls logged in and waiting attention. I looked at my hand samples again. Nichols would jump all over my decision- "Doctor?" the crewman asked.

"No, we're not," I answered in as firm a voice as I could muster. "We have problems with our equipment. I don't want to leave orbit until I'm sure of our data's validity."

There was a slight pause. "Understood. Astronomy has requested a ten-hour delay. Will that meet your needs?"

That man was a saint. Greely knew I'd need more time before I'd commit. And two requests for delay couldn't be refused. Ten hours? I had a feeling I'd want to go planetside again.