"You forget I have a searchlight," said Tony. "By the time the break comes, I could have Prometheus just outside Gargantua's shadow cone and in position to reflect some sunlight on the landing area. I won't be able to hold the sail in position for the whole two hours, but I should be able to cover most of the eclipse period."
"I was planning on using both the visible and the long infrared arrays at the same time, anyway," injected Linda. "I just have to insert a wavelength selective mirror in the ray path to pull out the infrared portion and send it to the infrared detector array. That way I can look for infrared signatures from objects warmer than the background, and correlate them with any visible spectrum signatures that match typical vehicle, spacesuit, coverall, and skin reflectance spectra."
"Skin reflectance! Are you going to be able to see individual people?" I asked.
"Sorry, no," replied Linda, again avoiding my eyes and speaking softly through her imp while her fingers flew over the touchscreen. "I'm afraid not. To keep the sail out of Gargantua's shadow, Tony is going to have to put Prometheus at least one Gargantuan radius from Zuni. That's a hundred thousand kilometers. The best resolution I can get with my ten meter telescope aperture at that distance is ten meters. But the Beagle made a careful multispectral survey of the beaches around Crater Lagoon before it went down to land, so we know what infrared and visible spectra to expect. If we see any sections of beach that are significantly different, then there is something new there. And if that something new has the right spectra and is far enough away from the high tide line, then someone escaped from the crash and is on the beach waiting for us to see them."
"I hope so . . ." I said soberly, and turning my eyes again to my screen I felt the command responsibility weighing heavily on my shoulders again. "Although if they got out, why haven't they radioed us?" I asked my imp. No one answered.
I got up from the console and headed for the lift shaft.
"I think I'll go up to the kitchen and get some coffee so I'll be awake when the break in the weather comes."
"No, you don't!" Sam yelled behind me. I turned to see him looking at Tony. "Tony—you're technically commander of Prometheus during this shift. You tell that bleary-eyed, baggy-suited, bone-weary, blowzy-bearded bum to go back to bed where he belongs. We'll wake him before the action starts."
"Sam . . ." protested Tony. "He's a Colonel and I'm just a Captain . . ."
I interrupted. "Sam's right, Tony. I'll go to bed like I should. Besides, now that I have something positive to look forward to, I'll probably be able to get some decent sleep this time. We don't know what we'll find when we're finally able to see the surface, but at least the uncertainty will be over."
Five hours later, the whole crew was on the control deck, either operating a console or looking over the shoulder of someone who was. Tony was flying Prometheus while Katrina had taken over the communications console. Linda was operating the main telescope at maximum resolution. She had three helpers, each one monitoring one of the magnified images the telescope obtained in different parts of the spectrum. Sam and Red watched the long- and short-infrared images and Thomas the visible image, while Linda glanced occasionally at the long ultraviolet display in case anything interesting showed up there.
Caroline was operating the laser ranger. She was set to scan the smoothly sloping beach areas around Crater Lagoon, looking for bumps in the topography that hadn't been there during the initial careful topographic survey of the island and lagoon. The laser wavelength had been carefully shifted to the short-infrared band to avoid any possible eye damage. Deirdre was operating the microwave sounder. Any strong returns from that instrument would indicate highly reflective metal objects. I manned the weather console. The display on my screen showed the actual multispectral cloud cover image superimposed on a computer map that indicated the positions of the various islands on the ocean-covered planetoid below.
"The last clouds of the front are starting to move past the location of St. Vincent Island," I said through my imp. "What's the time to eclipse, Tony?"
"It's starting right now," said Tony. I watched as the shadow of Gargantua began to take a bite out of the mottled blue, green, and gray marble on my screen. The eclipse darkness passed swiftly over the location of St. Vincent Island before the front cleared.
"I see a large circular glow through the clouds in the short-infrared," said Red.
"It's in the long IR too," said Sam. "That must be the lava in the central caldera of St. Vincent Mountain. It matches up perfectly with the caldera in the map overlay."
"Now that the rain has stopped, I'm starting to get decent returns out of the microwave sounder even through the cloud cover," reported Deirdre.
"Any returns?" I asked eagerly.
"None that weren't there before," said Deirdre, switching frequencies and repeating the scan. Every green blip in the return matched up perfectly with the faint blue outlines in the microwave reflectance overlay map that had been generated during the initial surveys.
"Damn!" I said, feeling the frustration set in again.
"That just means there's no metal on the beach," said Red encouragingly. "That doesn't mean there aren't people on the beach."
"What's that glow under the clouds to the south of the volcano?" said Thomas, whose sharp eyes had caught something in the visible display.
"Must be lava in another volcanic caldera," said Sam. "St. Vincent Mountain has a number of secondary calderas, and they're all potentially active."
"Nope! It's not!" said Thomas in an elated voice, as the cloud cover finally passed away and Crater Lagoon came into view. "Volcanic calderas don't come in the shape of a giant X!"
A half-hour later the clouds were covering St. Vincent's island again, and we switched our consoles to a replay of the action that had taken place during the short break in the weather. Sam was busy combining the output from all the instruments that had been looking at the scene. We had already seen one run-through and were about to repeat it with a different multispectral mix.
"Play it again, Sam," I said eagerly . . .A sense of deja vu floated through my fatigued brain. The answers to three trivia questions rose—unwanted but insistent—into my tired mind . . .
Ingrid Bergman said it; not Humphrey Bogart.
She said only; "Play it, Sam." There was no "again."
The tune was, "As Time Goes By . . ."
I shook my head to clear it of the unwanted memories and continued my sentence. "I want to make sure the count we got the first time is correct."
"OK," said Sam. "As I roll the video record again, James will put a circle around each blob whose infrared emission spectra and visible reflectance spectra matches a man-made surface or human skin. During the first run, there were definite matches with coverall spectra and hints of skin spectra, but no indications of metallic or spacesuit spectra."
"Which is why they didn't radio," I said. "The lander must have sunk so fast they didn't have time to put on suits. The atmosphere must not be too bad for them, if they've been able to survive this long. The main thing now is to find out how many of the crew made it to shore."
"By having James follow the blobs as they start the fire, tend it for a while, and then put it out, it is possible to gather information along the way that allows James to tighten the error bars on the size of the blobs, and determine how many objects were in each initial blob. Then, once Caroline's laser ranger passes over a blob, James can use that range data to pick out the highest point in the return from that area and get an estimate of the height of the person to within a centimeter. That's good enough to identify specific people, like Richard and Jinjur. Now watch again and count. I'll have James put a number by each blob as soon as it feels certain that the blob contains one distinctive individual."
"One, two, three . . .four . . ." I counted as the computer generated numbered circles around the scurrying blobs that moved up and down the fiery cross. Some of the circles split in two, and all of them became smaller and smaller until
a number appeared next to them. Sometimes the number was joined by a set of initials as a particular individual was identified.
" . . .seven VJ. That's Jinjur, all right. Standing near the center of the cross and telling everyone else what to do. Eight . . ."
" . . .and ten," completed Sam a little later.
"Ten SE," I added, feeling the massive but unseen weight of responsibility drop from my shoulders. "Once Richard was identified, the next tallest one had to be Shirley."
"So, it looks like all ten made it," said Sam. "In addition, there are indications from the visible spectra that a segment of the lagoon is redder than normal, with a spectra that matches Little Red, indicating that at least one of the flouwen escaped."
"I wonder how that happened?" asked Katrina. "They were sealed in the central water tank on the Beagle. If the crew didn't even have time to don suits, then they certainly didn't have time to release the flouwen."
"Somehow they did." I paused and took a deep breath. "Well," I continued grimly. "They're alive. For how long we don't know. Now . . .How are we going to get them out of there?"
No one had an answer.
"James!" I said to the imp on my shoulder. "Keep an eye on those clouds and let me know if they show signs of breaking again." I looked around the control deck at the eight faces waiting for my next sentence. "Let's all adjourn to the view lounge upstairs with a squeezer of coffee and have a brainstorming session. There must be some way we can rescue them."
"It's just as you told Jinjur when they left," concluded Red, a few hours later. "If both the Dragonfly and the Ascent Module fail, there is no way the exploration crew can return to Prometheus. We can't pull the same trick that we used on Rocheworld. There's no zero-gee point for the Ascent Module to descend to, and besides the Dragonfly plane is at the bottom of Crater Lagoon. Unless someone thinks of something new that this brainstorming session failed to find, they are marooned on Zuni until the follow-on expedition arrives some twenty-five years from now."
"If they survive that long," I muttered, beginning to feel weary again.
"If there was something drastically wrong with the atmosphere, they would have been dead by now," said Katrina. "Of course, there is the problem of food. Even if they can find something non-poisonous to eat, there is the potential of long term malnutrition due to lack of proper vitamins and trace minerals."
"Thanks for reminding me of that," I said, somewhat sarcastically I'm afraid.
"We could send down one of our exploration crawlers with a load of food, medicine, and vitamin pills," suggested Tony. "They can carry up to fifty kilos of cargo if the cargo is compact enough."
"The first thing we need to do is get them a radio so we can establish contact and find out what it is they think they need," I replied. "Fortunately, the crawlers have an outside microphone as part of their exploration sensor suite. Unfortunately, we'll have to wait until the weather clears completely before we attempt to drop in a crawler. The high winds in the jet streams could cause the crawler aeroshell to tumble and burn up, while the updrafts in the storm clouds could cause the crawler parachute to rip apart."
Thomas spoke up. "If all you want is to send them a radio, you don't have to use a crawler. Use one of the self-powered penetrator harpoons that Sam and I used on the twin moonlets, Zoroaster and Zwingli. Although they're designed primarily to gather subsurface temperature gradient and seismic data, they do have an external acoustic detector, so we can separate underground seismic vibrations from atmospheric vibrations like thunder and volcanic eruptions. That would be a perfectly adequate microphone. All we would need to do is add a speaker."
"And the best thing about the penetrators," added Sam, "is that they're rugged enough that they can pass through jet streams and storm clouds like they weren't there. Also, they are self-guiding, and as long as they can see a distinctive feature and match it with a preprogrammed map, they can hit any desired point on the surface within a few meters."
"Let's do it!" I said. "The sooner we give them a reply to their flaming cross signal, the better we all will feel."
"James?" said Sam to the imp riding on his shoulder. "Do you have a speaker that can take shock loads that we could add to a penetrator sensor suite?"
"Certainly," replied the computer voice back through his imp. "One of the standard options for the penetrator sensor package is an acoustic ranger designed for scanning the region around the landing point in order to more accurately determine the exact location of the penetrator with respect to surrounding surface features. Normally, a laser ranger is used, since it can be used as a crude video camera to build up a picture of the surroundings, but the acoustic option is available in case the atmosphere is expected to be opaque to laser light. The acoustic ranger has enough bandwidth that it would make a very adequate speaker."
"So we can either see, or talk, but not both," I said. "I already know what everybody looks like. I'll take the two-way talk option."
"Have the Christmas Bush get an acoustic ranger out of stores, and bring it down," said Sam. "Also, please send the shaft elevator to the Living Area Deck, so Thomas and I can use it to haul the penetrator down. We'll meet you near the airlock on the Control Deck."
"I'll come with you," I said, getting up to follow them.
We left the lounge and went to the central shaft. When the elevator arrived, we stepped on the donut-shaped platform.
"Level 14, please," said Sam, and the elevator rose up the long central shaft and came to a stop. Sam palmed open a panel. There was a honeycomb rack half-full of a dozen or so sharp-pointed metal tips. Thomas, having done this many times before, reached out and pulled at a small pointed tip centered in one of the hexagonal holes. Slowly, out came a meter-long metal spike about two centimeters in diameter. As he continued to pull, the tungsten carbide spike became thicker, then rapidly turned into a heavy exponentially tapered horn that was ten centimeters across. The metal spike was faired into the nose of what looked like a missile. The missile had a name painted in script on its side. The name was "Crash."
As Sam and Thomas took the long missile under their arms, James was filling the miniature memory of the penetrator missile with the optimum trajectory information, and a model of the surface features of the beaches around Crater Lagoon. Once the missile knew what its target was to be, it started looking for it.
"Where is it!?! I'm gonna CRASH right into it!"
"Just wait a few minutes, Crash," said the lanky geophysicist. "We have to replace your ranging package first, then get you through the airlock." Just about that time, a portion of the Christmas Bush floated down the long central shaft of Prometheus, flying itself to a halt on the platform by the rapid motion of the thousands of tiny cilia on the ends of its bushed-out branches. It was carrying a cylindrical package that was the same diameter as the end of the missile. One end of the package had a male screw thread and the other end a matching female thread. Inset at four places around the perimeter of the package were four round ultrasonic senders.
"This screw-in segment replaces the laser ranger segment, the second from the end, between the acoustic sensor segment and the communications package at the rear," said the Christmas Bush.
With Thomas holding the spike, and I the nose, Sam unscrewed the communications cylinder, replaced the laser ranger with the acoustic ranger, and screwed the whole package back together again. By the time he had finished, the elevator platform had reached the command deck. Sam and Thomas hauled the missile over to the airlock, and Sam cycled the airlock controls. The Christmas Bush carried the harpoon-like penetrator missile through the airlock, and when the outer door opened, tossed it out into space. The missile fell slowly for a while until it was safely away from the habitat, then started its main engine.
"I've got it!" said Crash. "Here I go!"
Four hours later, I and the rest of the crew on Prometheus were at our consoles watching and listening as the telemetry signals from Crash sent back a crude video picture of what the missile was s
eeing with its seeker. The acoustic sensors in the tail returned the sound of a high-pitched scream that grew louder as the air grew thicker, until James was forced to lower the volume.
"It's found Crater Lagoon . . ." said Caroline. "Now its locked on the remains of the burned-out cross . . ."
I began to feel the excitement grow within me as this portion of the mission came to a successful conclusion . . .I was soon going to be back in contact with Jinjur and the rest of my crew . . ."It's going to hit right in the center of the X!"
The video return went black, but the whistling sound collected by the acoustic sensor in the tail of the missile exploded into a crack of thunder that rolled higher and higher in the heavens until it segued into a sonic boom. As the thunder rolled away, the sound of wind, light rain, and lapping water could be heard.
"The antenna boom has deployed," said Caroline from the communications console. "And James has hooked your imp up with the speakers on the tail."
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