Castaway Planet (3 page)

“A month.” Mom shook her head. “And each light-year will be a couple of weeks, roughly, at the speed we can reach in
LS-5
. Then . . . we really have to hope there is a solar system within one or two light-years. Normally two weeks is pushing it for a Bemmie. I’ve got some ideas on how to stretch that—there are recommendations in the literature—but I don’t know if I can stretch it more than two months.”

Sakura tried to hide her dismay. The chances weren’t great that a star was that close. They weren’t
terrible
—maybe one in two or three—but still, not certain. And even if there were stars nearby, they might not have good planets.
And even if it weren’t for Whips . . . there’s not all
that
much food on board, especially since Whips’ll eat more than one of us. We’ve got a nuclear reactor with power for years, but our supplies won’t last that long.
She glanced at Hitomi—staring back with wide, terrified eyes—and Melody, gripping her seat’s arms so tightly the knuckles were white—and then at her mother and took a breath.

“First thing to do is find out where the nearest star is, I guess,” she said. “I mean, if we
are
in a solar system, no problem. Everyone keep an eye out.”

Her hands tried to shake, and she paused and took a breath before she reached out to the controls again.
Simple. Just a full look around. Methodical, careful, controlled, just like in training.

The gyros and stabilizers could be used to spin the ship without having to use any of the limited reaction mass, so she used that, carefully rotating
LS-5
around its axes so that all portions of the sky slowly drifted across the forward field of view.

Stars swam by, and everyone in the ship watched tensely. The beautiful river of light that was the Milky Way pinwheeled around them. Bright stars, dim stars, stars with a hint of red or yellow or blue or pure white shone unflickering against the absolute black of space.

“Anyone?”

The others shook their heads. “I saw some pretty bright stars,” Whips said, “but nothing that looked like it had a disc. At a light-year away, I think the Sun would only look like a bright star—”

“Magnitude about minus three,” Caroline said. “So yes, even if we’re close to a good star, if it’s even a large fraction of a light-year away, we won’t see it as a disc. And without knowing what kind of star I’m looking at, I can’t make a guess as to how far away it is.”

Sakura knew what she meant. Given how much stars varied in their actual light output, a really bright star could be a tiny red dwarf just a fraction of a light-year away, or a supergiant star hundreds of light-years off.

“But . . .” Caroline continued, smiling, “we don’t need to worry about that. Sakura, just charge up the Trapdoor Drive and give us a few hours hop in any direction.”

Sakura laughed, feeling some slight relief.
At least we can find out how bad we’re screwed.
“Parallax, right?”

“Right. Move only a little ways and we should be able to see movement of a nearby star against the background of the others. You recorded the whole globe of stars around us, right?”

“Yeah. And really, only the
very
bright ones matter, I think—over first mag, probably.”

“I’d guess you’re right. That’s only twenty or so back home, probably not much more than that here. We can track that pretty easily.”

“Okay, then—can I do that, Mom?”

Her mother smiled. “Of course you can. ‘Make it so,’ navigator.”

Sakura heard the first chuckle since the disaster go around the cabin. “Aye, Captain!” She turned back to the controls. “Unsealing Trapdoor Drive controls. Drive shows green. Coils charged.”

Despite the desperate circumstances, she felt a thrill go through her. Her first solo flight . . . and she was doing a hop in interstellar space!

“Since we have no idea which direction we want to go, I’m just jumping the way we’re pointing. Set for four hops, total distance a few light-days. We’ll check the big stars after each hop, while the superconductor storage coils are charging. Okay?”

“Sounds good to me, Sakura.”

She found herself holding her breath as she reached out and touched the activation button.

Without a bump or jolt, the universe outside disappeared, and the Trapdoor Drive sent
LS-5
hurtling on its unknown course. “Trapdoor Drive activated! We’ll be under drive for . . . about one hour and ten minutes.”

This is going to be the longest hour
ever
.

Chapter 4

The stars shone out again, and she bent forward. “Coils recharging. Doing a full survey of the sky again . . .” She tumbled
LS-5
once more around its axes. “Generating full sky view . . . okay, everyone, start looking. I’m blinking our virtual displays between the first panorama we got and this one. I’m sending different areas of the sky to—”

“
Got one!”
sang out Caroline. “Brightest star in our sky just jumped a beautiful, beautiful big fraction of a degree! Measure that arc, Sakura!”

“It’s . . . about an eighth of a degree,” she said after a moment, feeling a smile spreading over her face. “That’s less than a light-year off, right?”

“About zero point two seven light-years, I think, which given the brightness means we’re probably looking at a G-type star!”

G-type star
. She heard the words with a tremendous lightening of her heart. That was the best possible candidate for a world they could live on.

She heard both her parents let out their breaths in a sigh of relief. “That’s wonderful, Caroline, Sakura,” her mother said. “But let’s not jump the gun. See if any other stars move.”

No one else spotted any that they were sure of, and by the time they were done, the second jump had begun. After another tense-yet-boring wait, Sakura repeated the maneuver and started the comparison running again. This time, Hitomi spotted two more that she thought moved. A close comparison showed that she was right, but the movement was small compared to the now very noticeable movement of the first star. One appeared to be a red dwarf about three light-years out, and the other a brighter star five light-years away. No very bright stars were directly ahead of or behind them, so they weren’t heading straight towards or straight away from any possible candidates.

That was enough for her mother. “All right, then. Sakura, cancel those other jumps and get us headed towards that star, okay?”

“Yes, Mom—I mean, Captain.” She felt much steadier this time as she set the course. “Given that we’re this close and moving as fast as we will be, I don’t need to do a fancy navigation calculation. Just point the nose at our target and drop out to adjust our course maybe once a day. We’ll be about there in a little less than four days.”

“That’s just fine, honey. Hold off on the jump for a little bit. Everyone, unstrap for a moment so we can all talk together,” said her mother.

The others unsnapped quickly. It took Whips a little longer to release all his hold-downs.

“First . . . all of you, come here,” Laura said. She reached out and hugged little Hitomi to her, and gestured the others close.

Then her mother looked up as the family gathered, straight at Whips. “You too, Harratrer.”

She could sense a momentary protest that he was too old to need special treatment. “Come
here
, Whips,” she said, and heard her voice waver. “You’re our family too.”

The patterns that rippled chaotically over Whips’ skin showed that he, too, was close to the equivalent of tears. He drifted over to the others and wrapped all three arms around the Kimei family; Sakura and the others gripped his arms and hands, and even though he was so very different . . . it was still exactly like a hug from their own family.

For a few moments they all hung there, not moving, just accepting that for now, they were together, and a family, and safe.

Mom smiled finally and spoke up. “That’s right. We’re all here, we’re all alive, we’re together, and no one’s hurt. Right?”

Hitomi nodded, brightening. Melody, eyes still huge and frightened, also nodded.
She’s smart enough to know we’re not anywhere near safe yet.

“Right!” said Sakura; her attempt to sound confident and ready didn’t fool Whips, she was pretty sure, and probably not her parents.

“Of course, Mom,” Caroline agreed.

“Exactly right,” Dad finished. “I won’t pretend we’re not in trouble—not even to you, Hitomi. But we could be in much worse trouble.”

“We’re already trying to figure out where we are, and where we have to go,” Mom said decisively, letting go, and allowing the others to slowly drift back to their seats. “I’ve never heard of a Trapdoor Drive failure before, but then I suppose if it happened it would be hard to get news of the failure. Is it possible we’re somehow near our destination?”

“I wouldn’t expect so,” Whips said slowly. “I mean, I’m just an apprentice right now, but I’ve been studying real hard to understand all the key engineering stuff. We were only halfway there. I don’t know how it’d be possible for us to jump the rest of the way so fast. If ‘fast’ is a reasonable term, I’m still finding the swimming
really
hard with understanding relativity and such. Still, it looked like the field just . . . deformed and dropped us off. We’re still probably about halfway to our destination.”

“But space is pretty much empty,” Melody said, her voice trembling a little but her tone going to the lecturing one that she liked to use whenever showing off what she knew. “And our destination was EC-G5-4-100-11 Tantalus, which doesn’t have any stars I know of right along our route.”

“Can we tell if this is the right star?” Akira asked.

Sakura thought, then shrugged. “How? If we get close enough or we find a planet we might be able to tell.
LS-5
doesn’t have any spectroscopic software on board.”

“My omni does,” Melody said.

A ripple of stroboscopic surprise washed down Whips’ body. “Why in all the oceans would you have spectroscopic software?”

“I was playing with chemical analysis packages,” Melody answered defensively.

“It’s all right, Melody; he wasn’t saying there was anything wrong with it, he was just surprised. As am I,” Caroline said, “but if you’ll let me access your omni we might be able to use it.”

Melody gestured vaguely in the air, and her omni-personal communicator, database, toolkit, entertainment center, and more in one—generated a green light. “Go ahead.”

“From the designation,” Caroline said, “we know that Tantalus’ primary is a G-5 star and Tantalus itself is the 4th planet out from the primary. So the first thing to do is to find out what type of star that is.” She looked at Sakura. “Which camera input should I use?”

“Umm . . . Hold on a minute.”
Where are the specs on all these things? Oh, there’s the info tags . . . Okay!

“The forward nose camera is continuous spectrum sensitivity from deep infrared through far UV—that’s between about twenty-four microns down to two hundred nanometers,” she said finally with relief. For a moment she had wondered if in fact there were any full-spectrum, unfiltered cameras available. She refined the alignment of
LS-5
and made sure the target star was centered. “There you go, Caroline.”

“What’s the camera designation?”

“Sorry. It’s simply designated as camera Alpha in the main systems.”

“Okay, I have the input stream. Melody, direct your spectroscopic app output to my omni, okay?”

“Okay.”

A few minutes passed, then Caroline sat back with a smile. “Based on the spectrum and apparent temperature, I’m reasonably confident—though not certain, because these aren’t ideal conditions—that we’re looking at a G-3 main sequence star. So it’s not Tantalus’ system, but it is, at least, the type of system we’d like to be in.”

“The Sun’s a G-2, right?” Whips asked.

“That’s right,” Sakura answered, glad she knew some of this. “A G-3 will be just a little tiny bit cooler and smaller than the Sun, I think, but we won’t notice the difference.”
If there’s a planet to land on, anyway.

“Well, in that case,” Akira said, “I think it’s time to get things started and for me to get out some food. It’s past lunchtime, after all. Hit the jump, Sakura.”

He looked apologetically at her friend. “I’m afraid . . . we don’t have very many rations for Bemmies, Whips.”

“I didn’t expect you would,” Whips said calmly. Sakura bit her lip. The Europan Bemmies weren’t obligate carnivores, but they did need a lot more protein—of the generally animal sort—than anything else. The more “balanced” human rations wouldn’t be terribly good for Whips, and he’d have to eat a lot more of them, even in proportion to his size. How long would their supplies hold out?

“We’ll have to make do,” her mother said. “I know they’re not ideal for you, Harratrer, but we have I think three months’ supplies. Even with you onboard, we should be able to keep going for two months, and that should be more than enough now.” Unspoken was the fact that immersion issues might become acute long before then.

“Thank you, Dr. Kimei.” Sakura could tell that Whips’ formal-sounding voice hid much more relief and gratitude.

They’d found a good star. The drive was working. Maybe they’d get out of this after all.

Chapter 5

The unnamed star glowed before them, a visible disk, as
LS-5
came out of the Trapdoor Drive.
Now the next cycle of worry begins
, Whips messaged to Sakura, who gave a tense, wry grin.
Finding a good star was excellent luck . . . but we cannot live on a star
.

Yeah. But let’s take one problem at a time.
He saw her shove the worries out of her mind and concentrate on trying to figure out their location.
We’re already moving some with respect to the star, so if I can get any parallax at all that will give me a good idea of distance. I can
sorta
guess based on the likely diameter of the star, probably about one and a quarter million kilometers, but it could be significantly more or less than that.

Finally she shook her head and sat back. “I’ve got a rough guess as to our distance, but it’ll take a while to refine that and get a velocity vector. At a guess, we’re maybe two AUs from the star.”

“I
thought
the star looked a lot more than Europa-sized,” Whips said. “I mean, the size the Sun looks from Europa.”

“Yeah, that was really all I had to go on, given the uncertainty in the Trapdoor transit distance. If it’s a yellow supergiant I’d be totally wrong . . . but I don’t see all the gas and stuff it should be shedding if it was a supergiant, and if that’s what it was we’d be pretty much out of luck anyway, so it
has
to be a regular G-class.”

Caroline nodded. “Besides, if it was a yellow supergiant it would have been
incredibly
bright at a quarter light-year distance. Trust me, it’s a regular G-3.”

“Why do we have to wait to get parallax?” Laura asked reasonably. “Just do a quick jump with the Trapdoor Drive.”

“We
could
do that,” Whips said, since he saw Sakura looking uncertain. “But the Drive doesn’t come up and go down fast; what happened to separate us from
Outward Initiative
is almost certainly partly due to something trying to do a fast adjustment on the field. You’re deforming spacetime itself, after all, and that’s something you need to do very, very carefully. So . . . in practice you don’t want to do jumps shorter than, oh, thirty seconds or so, which since that’s going to be a full continuous jump instead of one that’s interspersed with recharging moments, that’s a minimum jump of . . . well over seven hundred million kilometers.”

“Oh.” Laura’s brow wrinkled as she accessed the data. “Ah. That means that even the shortest practical jump covers a distance almost as far as Jupiter from the Sun.”

“Roughly, yes,” Whips agreed. “There are special drive designs that can do shorter, faster jumps, or ways to tune these for that, but . . .” he gave the rippling gesture of arms and color that was his equivalent of the human’s shrugs, “I’m an apprentice. I know the theory but no way am I going to try doing that in practice.”

“We wouldn’t want you to!” Sakura agreed emphatically. “So that means we need to just let our own speed give us the parallax, and then we can deploy the Nebula Drive to get us to our target.”

Whips actually looked forward to that. The “Nebula Drive,” or more technically the “dusty-plasma sail” had been originally invented by
Bemmius secordii sapiens
—not his direct ancestors, but the ones who’d seeded his ancestors on Europa. Human scientists such as Dr. Robert Sheldon had theorized it was possible, but it wasn’t until an ancient
Bemmius
relic had been uncovered and repaired that the Nebula Drive was simultaneously reborn and renamed, a method for using ionized plasma to inflate a magnetic field to immense sizes, confining dust and gas within the field and providing the most ethereally beautiful, and low-cost, way to move around a solar system.

“
Can
we get closer to the star?” her dad asked. “I don’t want to worry anyone, but I know the only other long-distance capability we have comes from the Nebula Drive, and that’s sort of like a solar sail, right? So I can see how it can push us
away
from the star, but . . .”

“Remember that we’re not just sitting still with respect to the star,” Whips said. “So the real key is which direction you are orbiting the star, and at what distance.”

“Right,” said Sakura, picking up the conversation, “To oversimplify, you just point your sail so you go against your orbiting direction, and that’ll make you go closer. You can tack with a dusty-plasma sail just like a regular sail. If we can find a good-sized gas giant somewhere, we can also use the gravity assist to send us in the right direction.”

Hitomi spoke up. “And we need to find a planet to land on. So we should be looking for planets now!”

Whips was impressed with his friend’s self-control, as Sakura managed to keep a smile on her face at Hitomi’s innocent assertion. Whips didn’t need to read the datastream from Sakura to know what thoughts were going through her head.
There might not
be
a planet to land on. Probably won’t be. Only one of ten stars like this have good planets in the habitable zone—which is a whole
ocean
of a lot more than they used to think there would be . . .

Aloud, Laura Kimei said, “Hitomi’s completely right. Caroline?”

Caroline looked uncomfortable. Whips knew that she hated doing things halfway, or out of order, or, well, just not the right way—and there was nothing “right” about this situation at all.

But she sat up straighter and nodded. “The most puzzling thing to me is that this star is just not on the charts. I checked with what I had from Earth, and if we did just drop off where I think we did, there
aren’t
any stars where this one sits. Nothing. If there was, the big wide-baseline telescopes in our home system would have mapped any planets in detail, especially habitable ones, even if no one actually went there. But there’s nothing. This star shouldn’t be here . . . but it is here, and I guess we should just be grateful it is.

“But that does mean we’ve got to do all the survey work ourselves, without a single clue as to exactly what we’re looking for or where it is.” Caroline sighed, pursed her lips, then nodded again. “We’ll need to get all our omnis linked in to the different cameras and do running background comparisons. Stars don’t seem to move appreciably at orbital speeds, so what we’re looking for are dots that move with respect to the background of the stars.” She sighed. “If
LS-5
were meant for this kind of work, it could run the whole comparison by itself while we slept even without the AI, but it was just meant to follow beacons to orbits and landings and take sights only when it knew pretty well what it was looking for. And when we were looking for a nearby star, well, we were looking at the few very bright stars in the sky. Planets might be pretty dim stars, especially depending on what angle we’re viewing them at.”

“Can you program the omnis to do the comparison?” Whips asked.

Caroline hesitated, then nodded. “I have a comparison program from my studies, actually. It can be transferred. But . . .”

“But . . . ?” Laura Kimei prompted.

“But . . . well, without any benchmarks it’s going to be really hard to know what we’re looking at. Oh, you can tell the characteristic banding on a gas giant pretty easy, but how do you know if you’re seeing one that’s closer in or farther away? We don’t even know which direction we are going yet.”

“Never mind that,” Laura said firmly. “First let’s find planets. By the time we find some, I’m sure Sakura will have gotten enough data to tell us how fast we’re moving with respect to our star and we can really start nailing things down then, right?”

“Yes, Mom,” Caroline said after another hesitation.

They all acquired the running comparator program a few moments later. “I’ve picked out some bright stars as landmarks,” Sakura said. “
LS-5
will use those to keep our orientation the same, so each of us has our own camera to focus on and the view won’t shift.”

Maybe a silly question,
Whips sent to Sakura,
but what if you’ve picked a planet as one of your landmarks?

Oh, come
on
, Whips, don’t you think I
thought
of that?
The transmitted voice came with a grin-symbol, so he knew she wasn’t really annoyed.
I put full magnification on each one to make sure it didn’t change size and got a partial spectrum off each using Melody’s program; they’re emitters, not reflecting the local sun, so yeah, they’re all stars.

Good.
He hesitated, then,
You know the odds are . . . not good?

Yeah
, she sent back after a few moments.
One out of ten chance there’s a decent candidate, and then there’s the question of the biosphere.
She looked at her father, who had subtle frown lines on his normally cheerful face.

He knows—better than anyone else—what those odds are.

They’re
great
odds . . . if you’re not worried that your life’s being bet on them,
Sakura sent back.

That much was true, he had to concede. Out of all of the extrasolar planets found to harbor significant life, one-half had a biosphere that was, astonishingly, compatible with Earthly (and Europan) lifeforms.
Why
this was true was a source of spirited, not to say flamingly acrimonious, debate between biologists and allied professions. Some held that it was simply a matter of chemistry. There were only so many easily assembled building blocks of self-replicating chemistry, and the ones that Earth and Europa were based on were some of the most easily synthesized, and so it was just likely that similar lifeforms would evolve. Others had championed the old idea of Arrhenius’ “panspermia,” that life had evolved somewhere else a long time ago and been spread through the universe by light pressure or similar phenomena. But so far no one had found an unambiguous example of such spaceborne spores.

No matter the actual source, it was true that half the lifebearing planets found had compatible biospheres—although “compatible” did not in any way guarantee it was safe, or even easily digestible. The other half . . . were not compatible and generally lethal.
And vice versa, of course—an animal of those biospheres eating me would likely die in agony
.

So . . . one chance in twenty, then. We beat odds like that all the time in those card games.

Sure,
agreed Sakura, darkly.
But if we lose
this
game we won’t be starting another.

Little Hitomi grew bored of the comparator fairly quickly and drifted through the air to start climbing on Whips, playing with her stuffed flying wolf along the way. Whips sighed, but tolerated it. He was bigger than everyone else, so she’d bother him less than the others. Besides, there was more of him for her to climb on. He quickly found he could keep her amused by wiggling his rear anchors gently so she had to hold on—and sometimes came off to drift away, so Hitomi had to bounce her way back, giggling.

It was still somewhat distracting, but he was able to focus on the comparator data. The running comparator would flick back and forth between images in the field of view of interest, and kept the original images as the start point while constantly updating the second image with new data. Any planets, then, would show an increasing oscillation as the images flicked between original and new images.

“One here!” crowed Akira suddenly. “Definitely moving back and forth!”

“Wonderful, Dad!” Caroline said. “Show me!” She studied it for a moment. “All right, Sakura, I’ll need our full magnification on that location for a minute.”

“Hold on . . . I’ll rotate us. Okay, there, we’re steady.”

The built-in telescopic optics in the forward imaging system gave Caroline a high-quality image to look at. “Ohh, how
pretty
!
”
she said a moment later, and projected the picture onto the forward screen for everyone to see.

Whips had to admit it was quite pretty, even to his perceptions, which weren’t quite the same as those of his human friends. It was a good thing they had displays which actually emitted the intended wavelengths, instead of that old human red-green-blue system; or he’d only be able to make out shapes in those displays.

In the projected image floated a slightly flattened sphere, banded with rippled stripes of startlingly bright colors. Based on what he knew of human perceptions, they ranged from bright red through purple and even some definite green, though he’d use different names for the colors back home. “That seems even more spectacular than Jupiter. What is it with all those colors?”

Caroline shook her head absently. “So many possibilities. Though I looked at the spectrum of the star, and this planet, and I’m pretty sure this system’s got more heavy elements in it than ours. So it might be a higher concentration of complex compounds in the atmosphere.”

“Well, that’s one gas giant,” Laura said. “We need to find others, presumably closer to the star. Sakura, have we gotten enough parallax to estimate distance?”

“I think so.” His friend stared vacantly into air for a moment, seeing her own display. “Um, yeah. Looks like we’re just a hair over one point two AUs from the primary, which refines all my other estimates!”

“Where’s the Goldilocks Zone?” asked Hitomi, startling them.

“I’ll tell you in a second,” Caroline said, but Melody, who’d been mostly silent, interjected, “Centered at one hundred thirty-seven million kilometers.”

Caroline looked at Melody. “How—”

“Well, I’d brought up the data on calculating it earlier, so I just caught Sakura’s data and threw it in.”

“So
what’s
the Goldilocks Zone?” asked Hitomi.

“You remember the story of Goldilocks and the Three Bears?” Sakura asked. When Hitomi nodded, Sakura went on, “Well, then, the Goldilocks Zone is the region around the star that’s ‘just right’—not too close and hot, not too far and cold—for planets like Earth.”

“Oh! That makes sense!”

“Sakura, my measurements agree with yours,” said Caroline. “If that’s the case, then Whips and Mom have the best views of that region, at least where we currently are. But some of the Zone is going to be out of sight or hard to differentiate behind the primary.”