Saturn Rukh, page 13
“That does not sound like a viable mode of living,” said Seichi, dubiously.
“It takes a month or two for the mature sinkers to fall,” said Sandra. “As long as they can reproduce a new generation of tiny sinkers in that time period, then life goes on. The more successful lifeforms have learned to float or swim, although most swimmers also have flotation bladders.”
She cleared the screen. “I think I’ll go get a cup of coffee.” She clambered down the ladder to the galley on the deck below, while Seichi returned to his post at the scottyboard.
When Sandra turned away from the galley, sucking on the hot squeezer, she saw Dan standing at the door of the engineering sector, holding a glass tube with stoppers at both ends and hoses running into the stoppers.
“I rescued him,” said Dan, holding up the tube.
“Who?” asked Sandra, bewildered.
“The drowned jellyfish,” said Dan. “Fortunately, the water protected him from the oxygen in our atmosphere until I could transfer him to this tube and evaporate the water away with some oxygen-free outside air. Nearly blew him away in the process, but now he’s stabilized. See him ... up near the top ... swimming upward toward the light.”
Sandra looked at the pulsating microscopic glitter floating in the air inside the glass tube.
“Half-balloon, half-jellyfish,” she said, looking carefully at the tiny speck. “A toroidal bladder of hydrogen to provide buoyancy and hoop stiffness, a mouth that gulps air into the top of the hole in the toroid and squirts it out the bottom to provide jet power, and fine sticky tentacles waving in the jet exhaust to capture anything worth eating. Awfully tiny for a floater.”
“Floater and swimmer,” Dan reminded her. “Saturn’s air is ninety-four percent hydrogen and only six percent helium, so there isn’t much density difference between the pure hydrogen in his flotation bladder and the hydrogen-helium air mixture outside. When he stops gulping, he starts sinking.”
“Needs to get a lot bigger before he becomes a true floater,” said Sandra. “What should I call it, Jeeves? It’s a ring-shaped creature that swims to keep alive.”
“The Latin name for a ring- or annular-shaped swimming creature is Annulus natare, “ replied Jeeves.
“Sounds good to me,” said Sandra cheerfully.
“The motto for these tiny guys is ‘Eat to live,’ “ agreed Dan. “I wonder how big a ringswimmer can get?”
~ * ~
The scientists back on Earth were overjoyed that Sandra and Dan had not only identified a new species on Saturn, but had actually captured a sample of it, which could be frozen and analyzed later on Earth. They were slightly disappointed later when they learned that Jeeves and the nanoimager onboard had been able to determine the chemical makeup and genetic structure of Annulus. It wasn’t too much different from life on Earth.
“Not surprising,” said Dan, after Jeeves had given its initial verdict. “Asteroids strike all the planets all the time, and some of them are powerful enough to throw off large blocks of rock or ice into space, with microscopic spores hidden inside the cracks. It would take just one rock, blasted off from the Earth’s surface billions of years ago, to infect Saturn. After all, as we have found, the environment under the clouds of Saturn isn’t that much different from the environment a few hundred meters beneath the surface of Earth’s oceans.”
“A detailed study of the gene pattern should be able to determine when the Saturn genetic pattern deviated from the Earth genetic pattern,” said Sandra hopefully.
“I’m sure it will,” said Dan, reassuringly.
“I’m afraid that is not going to be exciting enough to get the Congress-critters to spend more money to come here for scientific purposes,” interjected Rod.
Rod was right. Although the scientific community was very excited over the finding, the public and Congress soon relegated the discovery to the category of: “another kind of jellyfish,” although some of the more intelligent ones added: “on Saturn.”
~ * ~
The dawn of the next day found the Sexdent hanging below the water cloud layer. The balloon itself, a kilometer above them, was still inside the clouds.
“Wake up, you sleepy heads!” called Chastity through the intercom to the habitats. She had been standing watch at the pilot console while the rest of the crew slept through the short Saturnian night. “Wake up and look out your viewports! I can see down! And I mean down!” She adjusted the multitude of floodlights on the outside of the capsule so they were all pointing downward. Inside their habitats the rest of the crew woke from their five-hour night’s rest and rotated the tilted viewports in the ends of their habitat tubes so they too could look down. The view below them was free of visible clouds, but they could see no surface. The floodlight beams just faded out in the distance far below them.
“That sure is a long way down,” said Pete over the intercom as he stared down into the blackness from the comfort of his bed.
“And the lower you go the hotter it gets,” said Dan, who was also looking down from inside his habitat. “Say, Chass,” he added. “What is the temperature outside? Should be above freezing now that we’re under the cloud layer.”
“It is,” replied Chastity. “Temperature is eight degrees C. That’s warm enough that we don’t even need to wear our saturnsuits anymore. We can go outside in our coveralls. Almost like being on Earth—nearly one-gee gravity and room temperature air.”
“You must like to live in colder rooms than me,” said Rod from his habitat. “Besides, we still have the high pressure to cope with.” The reminder of the high-pressure environment they were in made everyone notice once again Rod’s high tenor voice from the hydreliox mixture they were all breathing. “What is the pressure anyway?”
“Just under ten bars,” replied Chastity.
“That’s a lot,” complained Rod.
“Ten bars is like being under only one hundred meters of water,” said Dan. “People have gone a lot deeper.”
“But not for as long as we will be doing,” Rod reminded him.
“That’s why we’re getting paid a billion each,” retorted Chastity. “Hurry up and get dressed, so you can take over this pilot console. We’re already ten minutes into my sleep shift.”
“Set it on autopilot and go to bed,” said Rod. “I’ll be up and take over as soon as I’ve had my coffee.”
Sandra was the first one dressed. While the others were gathering around the galley for breakfast and coffee, she skipped breakfast and took over the science console. Pulling down the biviewer, she set it on maximum photon amplification and maximum zoom, and started a scan.
After a while Rod came up the ladder, a breakfast bar in one hand and a squeezer of coffee in the other. After checking all the settings Chastity had left on the autopilot, he left the pilot console alone and went over to the science console to see how Sandra was doing.
“See anything?” he asked, then realized how dumb the question was. If Sandra had seen something, she would have announced it immediately, and everyone would be crowding around one of the holoviewports trying to see it too.
“Hard to see anything when it’s as dark as it is,” replied Sandra. “With the sunlight cut by a factor of a hundred by the ten-AU distance, and what sunlight there is left being absorbed by the three cloud layers above us, there’s practically no light left to see with.”
“I guess the creatures out there must be blind,” suggested Rod. “Like the creatures that live in caves or the bottom of the ocean.”
“Either that, or they would have to have eyes as big around as Sexdent to collect enough light to see at all,” replied Sandra. After a while, she finally whispered, “I think I see something. Get this bearing, Jeeves.” She lined up the biviewer crosshairs and pushed a button on the handgrip.
“I have both a radar and a sonar return from that point,” said Jeeves. “The object has a significant Doppler shift and width. It is coming in this direction and consists of a multitude of smaller objects moving in formation.”
Now that her brain had the clue, Sandra was finally able to “see” what she was seeing. “It’s a flock of snakes!” she cried loudly. Dan, resting in his habitat, trying to compose in his mind his next long-distance message to Pamela and the kids, suddenly flipped ends in his habitat, grabbed his biviewer from its holster in the end of his habitat, and with the guidance of Jeeves, soon had the biviewer focused on the long, narrow cloud.
“Or I guess I should call it a school of snakes,” said Sandra, as the cloud grew closer.
“Ribbonsnakes,” said Dan. “Like the ribbonfish on Earth... swimming in formation like a flock of geese, except they are swimming vertically instead of horizontally.”
The school of animals were indeed shaped like ribbons, very thin and very long, but wide all along their midsection. They swam through the air with a vertical waving motion. They looked like a ribbon waving in the wind, but instead of merely responding to the wind, they were the ones doing the waving, moving themselves along by pushing on the pockets of air they had crested. On each side of the “leader” ribbonfish, and one “wavelength” behind, were two other ribbonfish, riding on the “wake” the leader fish had made. The vertical “V” formation looked very much like those formed by migrating geese.
“Hey! What’s happening!” complained Dan, as the capsule suddenly spun on its axis, rotating the ribbonfish formation out of his line of view.
”They’re flying by, and aren’t going to get any closer, so I’m having Rod rotate the telescope around,” replied Sandra over the intercom link. “I want to get a close-up view of those creatures. I don’t see any eyes or mouth and they’re too thin to have a big gut.”
After the flock had flown away, Sandra and Dan had time to look closely at the enlarged images of the Infula natrix, or “ribbon-shaped swimming-snakes”—the name Jeeves and Sandra had given the creatures in order to avoid confusion with Earth ribbonfish.
“No sign of a mouth,” agreed Dan. “And awfully thin. The big ones are hundreds of meters long and four meters wide, but only a few centimeters thick. They certainly aren’t floaters. That’s a lousy surface-to-volume ratio for a balloon.”
“Pure swimmers,” said Sandra with certainty.
“With no mouths, they can’t be ‘hunters’ in the usual sense,” said Dan, highly puzzled.
“Maybe there is a mouth, but we can’t recognize it,” suggested Sandra.
“Well, I sure can’t,” said Dan. “And with no eyes they wouldn’t be good hunters anyway.”
“There are a number of dark spots spaced along the edges of the creatures,” said Sandra. “There seem to be more of them at the ‘head’ portion than along the sides and at the tail. Perhaps those are the eyes.”
“There could be a lot of small eyes like those on a scallop,” suggested Dan. “More for detection of shadows than for imaging.”
“Scallops have eyes?” interjected Rod, who had been listening to the two scientists while keeping the balloon headed north.
“Scallops have a couple of dozen cute little baby-blue peepers stuck up on stalks, all around the perimeter of the tasty part—the better to see you with,” said Dan. “If they spot the shadow of a predator, they snap their shells shut and the water squirting out between the two closing shells jet-propels them away from harm.”
“Scallops have eyes!?” exclaimed Rod again, more loudly this time. “I didn’t know they had eyes! I don’t think I’ll ever eat scallops again!”
“Then again, the ribbonsnakes may see by sonar,” said Sandra, ignoring Rod’s histrionics. “And those dots are some other organ.”
“Or maybe the spots are just pure decoration,” added Dan. “That’s the trouble with real alien lifeforms ... it’s hard to interpret what you observe.”
They finally gave up and stored the images away in the bottomless depths of Jeeves’s memory, remembering to send copies to their scientific colleagues back in Mission Control on Earth. The five-hour-long “day” was over, so they went back to bed for a nap, in order that they would be ready to search the skies when sunrise came again.
The next day’s search was highly successful. There were breaks in both the ammonia and water cloud layers, and yellow sunbeams would shine down to their level. In many cases the distant sunbeams would illuminate creatures floating through the air. Fortunately the telescope had motion compensation, so high magnification could be used, and they obtained brightly illuminated high-quality images of a number of different air creatures.
“This one looks familiar,” said Dan as he zoomed the telescope in on a large creature illuminated from above by a beam of sunlight. “It’s a bigger version of the Annulus ringswimmer that I rescued from the drop of water.”
“You’re right,” agreed Sandra as she looked at the jellyfish-like creature. There was a large toroidal balloon that provided basic flotation. Hanging down from the outer perimeter of the fat ring was a cylindrically shaped, slowly pulsating thin membrane that pushed the creature upward with each pulse. Acting in synchronism with the outer membrane was a smaller, conical membrane hanging down from the inner perimeter or “mouth” of the creature. When the outer membrane was contracting, the inner membrane collapsed, blocking the hole in the ring and forcing the thick air out the bottom to produce the jet pulse that pushed the creature upward. When the outer membrane was expanding, the inner membrane opened, drawing fresh air, laden with microscopic bits of food, inside for the next pulse. Both membranes were covered with long cilia that captured the food out of the air as it passed through the creature.
“Those pulsation cycles are taking almost a whole minute to complete,” said Dan. “That must mean that the creature is quite large. It’s hard to tell at this distance. Jeeves?” he asked, “What’s the size of that thing?”
“The outer diameter of the flotation ring is ten meters, while the total length from the top of the ring to the base of the outer membrane is about fifty meters,” replied Jeeves.
“That’s as big as the Sexdent!” exclaimed Dan. “It’s amazing how big the thing is, compared to the tiny specimen that we captured in the cloud net. You’d think a creature that large would spawn larger children.”
“For all its size, it is still very primitive,” replied Sandra. “There are jellyfish almost that big back in the oceans of Earth, and they too have microscopic spawn.”
“But you would think that because it depends upon a flotation ring to keep afloat, there would be a minimum size for survival. The membrane of the flotation ring can only be made so thin. The smaller the volume enclosed, the greater the proportion of the membrane mass to the total mass. There has to be a minimum size below which a ‘floater’ turns into a ‘sinker.’ “
“You’re forgetting that the ringswimmers can swim as well as float. When they’re small, they keep afloat by swimming, which is easy when you’re a tiny creature. At that size, swimming through the thick air here on Saturn is like swimming through molasses—you sort of ‘crawl’ through the air. Later, after they get bigger, and swimming is less effective, the flotation ring keeps them up between strokes.”
The short “sunlit” day was nearly over when Dan noticed a large water cloud forming in an otherwise clear patch of sky.
“Looks like a thermal column is forming over there,” he said, marking the angle to the cloud using the direction-finding. ability of the biviewer he was using.
“Where?” asked Seichi with some concern, for he was acting pilot for this shift. “I want to make sure I avoid it.” Jeeves marked it on the situation display. It was well off to the east, far from their planned track northward.
“A thermal column means hot air rising up from the lower depths,” said Sandra. “There’s bound to be some critters rising sunward along with the air. Rotate the telescope viewport around to that side, Seichi.”
“It’s a pretty big cloud,” Dan warned her. “Must be pretty dark underneath it.”
Fortunately, with the Sun setting in the west, the illumination was nearly perfect for viewing the contents of the rising column of air in the thermal.
Dan increased the zoom on the biviewer. “Specks!” he announced. “Thousands of specks!”
“Come on!” Sandra swore impatiently as she shoved the telescope drive icon to its maximum slew speed. Finally the specks showed up on the imager—greatly magnified compared to the maximum zoom available through Dan’s biviewers.
“Balloons!” she exclaimed as the slewing stopped and the images steadied on her screen. “Thousands of balloons!” Slowly she scanned the telescope up and down the rising column of iridescent spheres. “Big balloons rising fast near the top of the column until they disappear into the bottom of the cloud and smaller balloons rising more slowly down below.”
“That makes sense,” said Dan. “The bigger the balloon is, the better the lift-to-mass ratio.”
