∞ ∞ ∞
Ultimately they chose a landing area on a broad flat river valley, about five kilometers wide and sixteen long, with only low vegetation. Low tree-covered hills surrounded it, with the range higher to north. Beyond that was denser forest. The small river bisecting the valley wound through a gap in the hills to the ocean fifteen kilometers further downstream. They had a small inflatable boat, electric powered, virtually identical to several commercially available models on Earth, but the initial forays would be on foot or by air. Their plane—big brother to the drone, with room for a pilot and passenger—could follow the river to the coast, and orbital inspection suggested they could land on the beach. The one concern was that the valley might be subject to flooding if the river rose, in the spring perhaps, but the nature of the vegetation implied that it wasn’t likely, and since it was late-spring in this hemisphere and they weren’t far from the equator, meltwater floods wouldn’t be a concern until months after they’d left.
The river was also a source of fresh water, when suitably filtered. They had desalinizers for the ocean water should they need them, but this would be one less variable. They’d also need water to electrolyze, to break down into hydrogen and oxygen to replenish their fuel supply for the launch back to orbit.
∞ ∞ ∞
Sawyer and Patel were doing a final site inspection by remotely piloted drone, to avoid surprises on landing.
Over their shoulders, Singh watched the on-screen view. Sawyer piloted the drone across the broad valley a hundred meters above the ground, its radar penetrating the low, grass-like vegetation to track for potholes or small boulders that might cause trouble for the lander. There were a few scattered trees, but it wasn’t until the drone reached the end of the valley and banked over the hillside that Singh got a closer look at what was growing on the slopes.
“Are those pine trees?” she exclaimed.
“They sure like pines,” said Sawyer, “but isn’t this area a little warm for that? No snow.”
“True pines, yes, but related species grow in warm climates on Earth. Hawaii has Cook pines, Araucaria columnaris, although they are not native. But on an alien planet?”
“Sure, why not? What’s it called, parallel evolution?”
“Convergent evolution, but yes. It’s very surprising.”
“If it is anything like pine, that could be handy for building materials.”
“What do you mean, like a log cabin?” Singh shuddered. “No thank you.”
“Hey, it’s a step up from a sod house, but I was thinking more as feedstock for composites,” Sawyer said. “Throw some cellulose pulp into a large-size fabber and have it build whatever you want. Okay, it may not be cellulose, being alien and all, but it has to have similar properties, or it wouldn’t be a tree.”
“Trees without cellulose. Now that is an alien concept.” Singh said and grinned.
Patel brought them back to the task at hand. “We are not going to land in the trees. Let us go back up the valley.”
“Right,” said Sawyer, and continued the turn back to the general landing area. They surveyed the valley until they had identified a clear area about a kilometer in diameter, then commanded the drone to drop a homing beacon near its center. The package landed and unfolded itself, then extended a telescoping mast upward. The top of the mast contained sensors for wind speed and direction, which the beacon would transmit to the refueling package as it descended.
The refueling package was a small unmanned lander all its own, about a third the size of the crewed landers. The non-landing ships, Heinlein and the late Xīng Huā, had each stored one in an area taken up by fuel tankage on the other landers. The package contained a small nuclear power supply, pumps, electrolysis gear and cryogenic systems, everything needed to create the liquid hydrogen and oxygen propellants that the personnel lander would need to take off again. The Chandrasekhar would not descend until they were certain that the refueling gear was operational. The refueling package also contained a more sophisticated instrument package, which together with the original beacon would guide the Chandra to a pinpoint landing.
Chapter 9: First Landing
When the fleet was being designed and built, the political considerations had been almost as difficult to overcome as the technical problems.
The warp engine technology was American, although India, Japan and China were probably close to developing their own. The compact fusion engines that would provide the enormous power that the warp drives needed were Chinese, based on the toroidal tokamak concept. Other nations had fusion prototypes but nothing as compact or power-dense as the Chinese systems, and size was a key design constraint. Neither the Chinese nor the Americans were eager to give up their respective technology monopolies, but they were willing to work out a limited mutual sharing agreement and retain a duopoly on the core technologies for interstellar travel.
All the involved nations had manned space capability, with certain components or subsystems being the particular skill of one nation or group or another. Electronic systems were largely Japanese, reentry technology was split between the Russians and Americans, the Russians also contributed to life support. India and Europe contributed software with Europe also contributing general systems design, The docking hatches were based on a standard that traced back to the original International Space Station.
The five ships fell into two design classes. All had a docking mechanism at the forward end. The command ship, the Robert Heinlein, also had a central hub in its forward area with four additional docking ports arranged equidistantly around it, and another on the far forward end. The other ships could all dock to it in a cross or plus formation, providing a continuous pressurized volume connecting the ships, much like the early space stations. The Xīng Huā had also followed this configuration with the docking ports. In both the Heinlein and Xīng Huā, the fusion generators and warp drives were integrated into the ship.
This contrasted with the design for the Chandrasekhar, Krechet, and Anderson. None of the ships had the capacity to carry separate landing craft to take the explorers down to the surface of the planets and bring them back again; the requirements of launching from an Earth-like planet were too great. Instead, these starships were designed as landing—or rather shuttle—craft first, and the necessary fusion and warp systems were built into a separate ring-shaped module, the “warp donut,” that could detach and reattach to the landers. This design had the added advantage, to Chinese and American eyes, of keeping the details of fusion and warp technology limited to China and America.
The baseline mission plan only called for two landers, with the third held in reserve as a rescue vehicle should that prove necessary. With two operational refueling stations, they could land one on each planet and conduct the exploration in parallel, reducing overall stay time in the Centauri system.
The landing shuttles themselves were based on the “plug nozzle” or aerospike designs first proposed as long ago as the 1960s by Phil Bono, and periodically dusted off, refined, and even flown by early private aerospace pioneers. On reentry—or rather entry—the broad curved base of the ship would act as an aerobrake and heat shield, much like the old Apollo, Soyuz and Dragon space capsules. Liquid hydrogen was pumped through cooling tubes on the back of this heat shield, and the resulting hydrogen gas vented through the circumferential engines to protect them. The engines would power up just before landing to control the final descent to the surface.
To return to space, the heat shield or “plug”, surrounded by the ring of thrusters would act as an inside-out rocket nozzle, and aerodynamic forces acting on the exhaust would provide additional thrust. That the overall design of the landers, with their attached interstellar modules above the base, made an efficient fit to the teardrop shape of the warp bubble was a happy plus.
∞ ∞ ∞
“Centauri Station this is Chandrasekhar ready for undocking.” The five-person exploration crew were in their seats, the forward hatch at the docking st
ation was secure.
“Roger Chandra, we’re all buttoned up too. You are clear for undocking.”
Ganesh Patel, captain and pilot of the Chandrasekhar, reached over to his control panel and flipped the “Arm” toggle. A bright red border lit up around the edge of his screen to warn that the controls were now live. He touched an icon on that screen and heard a ripple of “clank” sounds as the docking latches retracted, and felt a small nudge as the mechanism’s shock absorbers pushed the Chandrasekhar back. He let that small impulse drift the ship back three meters and then gently tugged the hand controller to give an additional burst of speed. “Chandrasekhar is clear, we are moving to separation position.”
The ship glided back until it was five hundred meters from Heinlein and the others, then Patel pushed the controller forward briefly to stop the motion. One of the control displays showed a schematic of the connections between the Interstellar Propulsion Module and Chandrasekhar proper.
“Initiating the separation sequence now.” He pressed a button and felt a series of thumps and vibrations as valves closed, cable connectors detached, and clamps released. He followed the activity on the screen, and released a breath he hadn’t realized he was holding when everything went green. If there’d been a hangup at this point, the Chandrasekhar wouldn’t have been landing.
“Everything is clear,” he said. “I am passing control of the IPM to you Heinlein, on your mark.”
“Thank you Chandra. Mark.”
Patel pressed another button, directing the computer aboard the IDM to take commands from the Heinlein until further notice. It would hold here in orbit until Chandrasekhar returned.
“All right, I am clear of the IPM, how I am looking?” Cameras on the Propulsion Module focused on the heat shield/plug nozzle of the Chandrasekhar, doing a last inspection before reentry. Patel could see the image on his screens just as well as anyone on the station could on theirs, but it didn’t hurt to get a second opinion.
“You’re looking good, Chandra,” came the response. “Continue retreating to safe distance and let us know when you’re ready for deorbit burn.”
“Affirmative.” Patel adjusted the controls and glided the Chandra further away from base. It had to be clear enough to avoid any chance of damage to the other ships from its main thrusters, and as a safety margin in the unlikely case something blew up. So far it was as routine as undocking from a space station.
∞ ∞ ∞
Forty-five minutes later, Chandrasekhar had reached its designated orbit some kilometers below and ahead of Centauri Station.
“Chandra, Centauri Station here, your orbit looks good and you’re coming up on your burn window in twelve minutes. We’ll confirm your state vector at t-minus ten, coming up in ninety seconds from the mark. Mark.” The state vector was the collection of orbital parameters, altitudes and angles that would line the Chandrasekhar up for an optimum burn, placing them as close on track to the landing site as possible.
“Roger that.”
A few minutes later, the radio sounded again. “Okay Chandra, everything looks good. You are GO for entry burn.”
Patel’s face widened into a huge grin. He looked around, the others were smiling too. This was it. “Thank you very much. Chandra is go for entry burn.”
He toggled the switch which authorized the computer to initiate atmospheric entry, and poised his finger over the manual engine fire button.
“In five. Four. Three. Two. One. Fire.”
Even as he pushed the button, he felt the whine of the turbo-pumps on the retro engines spool up and the growing vibration and roar as they fired. The force pushed them all back into their seats, but gently. The ship slowed in its orbit and began to drop toward the surface of the planet.
The engines throttled back to idle as the ship continued its descent, and as the air grew thicker the ship started to tremble and buffet. Through the view ports the dark black of the sky began to lighten, taking on an orange pink tinge as the air heated to incandescence by their passage. As the orange light grew brighter he felt himself pushed back further into his seat, the gee force rising.
He scanned the instruments. “On track and on target; entry is nominal.”
They continued their plunge toward the alien planet below. The vibration became stronger as they encountered thicker atmosphere, and with it turbulence. The guidance computer started to throttle up the engines. The gee force increased.
Out the window the orange glow started to fade and flicker, with a deep blue behind it. As the ship continued to slow and sink into the atmosphere, the orange faded completely to be replaced by a deep blue.
“The sky is blue,” one of the landing team, Darwin, remarked.
“Of course it is, Rayleigh scattering,” said Sawyer. “The sky’s always blue on an Earthlike planet.”
“That sounds boring. And just how many Earthlike planets have you visited?”
The dark blue began to pale, and wisps of cloud could occasionally be glimpsed. Patel scanned the panel again.
“Ten thousand meters, we’re looking good.”
“You’re GO for landing, Chandra,” the call came over the radio. Which was good, since they didn’t have the fuel to make it back to orbit.
“Roger. We have the beacon. Landing radar is good. Locked in.” In a pinch, Patel could fly the landing manually. It would be tricky, but possible. As it was, with the landing radar and the beacon and weather info from the ground, the computers could do it all just fine.
After a few minutes, the gee force faded; they were at their optimum velocity for approach. “Five thousand meters, throttling up,” said Patel. “Sawyer, please call the numbers.”
“Roger that,” she acknowledged. She would read the numeric displays so that he could concentrate on the landing area.
The engine noise got louder and there was a brief gee surge as the ship slowed.
“Three thousand, range five kilometers,” Sawyer said, They were still coming in at an angle, which should straighten up soon.
“Coming down, two thousand, range one point five kilometers.”
“Fifteen hundred, one kilometer,” Sawyer continued the callout.
“One thousand meters, right over the target.”
The ship was now in a vertical descent directly above the chosen landing spot. “Okay, coming down,” Sawyer confirmed. “Seven hundred meters, four hundred.”
The trick was not to slow down too much too soon, or you’d run out of fuel before running out of altitude, which would be regrettable.
“Two hundred. One fifty.”
He throttled the engines up. Below them the exhaust started to scorch the ground.
“One hundred. Fifty. Thirty. Fifteen.”
The engine noise rose to a loud roar and through the window all he could was dust, smoke and steam. They must be close now.
“Five, three. Contact!” The enthusiasm in Sawyer’s voice at the last contrasted with her earlier deadpan updates.
He felt a bump as the landing pads touched the ground, a little unevenly, then a brief surge as the ship threatened to lift again. He reached the ENGINES OFF switch just as the engine valves shut under computer control, and the ship dropped back to the ground with a thump. Somewhere below he heard a crash as of some inadequately stowed equipment jarring loose and hitting something. The motion stopped. The engines were quiet. Patel heard the muted tick and ping of cooling metal.
“Centauri Station, Chandrasekhar has landed,” he called over the radio.
Around him the cabin rang with whoops and cheers.
Chapter 10: Post-Landing
Chandrasekhar landing site
The atmosphere had been extensively scanned and examined from orbit via spectrograph, sniffed and analyzed and chromatographed and tasted by remote landers, and deemed breathable. There was one more test before any crew members ventured outside without breathing gear.
“The tests all look good,” said Darwin. “Let’s deploy the canary.”
&n
bsp; It wasn’t really a canary, that traditional bird coal-miners had used as a warning against the buildup of toxic or explosive gases in mines, but rather a specially bred white lab mouse. It was genetically just as sensitive, perhaps more so, than a canary and closer in physiology to humans because it was a mammal. There wasn’t—to the limits of their instruments, which were enormously sensitive—anything in the atmosphere which would kill humans any faster than the usual trace brew of natural toxins and industrial pollutants in Earth’s atmosphere, or even in the air they breathed aboard ship, but there was something psychologically reassuring about seeing the caged white mouse, exposed to the outside air, happily running in its exercise wheel and otherwise acting like a healthy critter. That it didn’t suddenly turn green and sprout alien fungus from inhaling some exotic spore was a great relief.
“I officially pronounce the mouse still alive and healthy,” Darwin said some hours later. “Mission biology chief gives a GO for EVA.”
Of course, they would have to wear their purple Biological Isolation Garments, BIGs, for the first few days. They would take enough samples and run enough tests and culture enough specimens to be confident that nothing fast-acting was going to infect them. In theory, biomedical science was advanced enough that anything slow-acting could be isolated, analyzed and neutralized before much serious damage was done. Before setting foot back on Earth, they’d be confined to the Lunar Quarantine Facility for an extended period, but it was larger and more comfortable than the sealed trailer the returning Apollo Moon astronauts had been restricted to. The concern was an alien biology that might be just alien enough to evade easy detection by sensors designed to look for Earth-biochemistry life-forms, or to evade treatment by techniques developed for Earth organisms, but yet not so alien that Earth biochemistry wasn’t something it could feed on.
Alpha Centauri: First Landing (T-Space: Alpha Centauri Book 1) Page 5
