Polar Quest. Tom Grace

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СКАЧАТЬ not merely living but thriving in the superheated mineral-saturated waters of geysers and hydrothermal vents, environments lethal to most other forms of life on earth, scientists were forced to rethink their assumptions about the conditions that might give rise to life. Being more tenacious than anyone had previously considered, life seems to need only three things to start: heat, minerals, and liquid water.

      Walking past a row of thirty-inch in diameter metal spheres that contained liquid hydrogen for the station’s fuel cells, Collins approached the reason that NASA and a group of partner companies had financed this project. Fifty feet from the station stood a cobalt blue tetrahedron that was as out of place atop the glacial ice of Antarctica as Arthur C. Clarke’s monolith on the moon: the Ice Pick probe.

      Collins shortened the legs on his tripod, lowering the camera to capture both the hard lines of the probe’s first stage and the luminous parhelic circles. Satisfied with the composition, he adjusted the exposure setting and snapped another picture.

      ‘Hey, Philip, how’s the show?’ Nedra asked, her voice clear over his headset.

      ‘Amazing. You should come out and see it.’

      ‘I snuck a peek out the window. Just wanted to let you know we’re ready for another dip in the lake.’

      Far beneath LV Station, sandwiched between a glacier and the rocky surface of Antarctica, lay one of the largest lakes on Earth – a body of liquid water that could have easily been seen from space were it not concealed by the ice. When British and Russian scientists confirmed the existence of Lake Vostok in 1996, they theorized that heat rising from the earth’s interior through rifts in the crust kept the water from freezing. Seismic activity in the area increased the likelihood of hydrothermal vents in Lake Vostok, meaning that the lake had the water, heat, and minerals necessary to support life. What form that life would take, in a place isolated from the rest of the world for the last 20 million years, was the subject of great speculation.

      In 1610, Galileo pointed his telescope at Jupiter and discovered four moons orbiting the giant planet. This discovery came at a time when the whole of Western civilization believed that the earth was the center of the universe. News of Lake Vostok’s discovery and the possibility of life in its hidden waters coincided with the arrival at Jupiter of a spacecraft bearing the great astronomer’s name. During a fly-by of one of the moons discovered by Galileo – an ice-covered rock named Europa – the spacecraft transmitted a series of images as astounding to the scientists at NASA’s Jet Propulsion Laboratory as the discovery of the moon itself was to Galileo four hundred years earlier.

      Europa was named after the mythical Phoenician princess that Zeus carried off and ravaged. Detailed images from the spacecraft revealed a pattern of fractures on the frozen moon’s surface similar to ice flows in the Arctic Ocean – evidence that beneath Europa’s frozen shell lay an immense body of liquid water larger than all Earth’s oceans. Dark regions mottling the moon’s surface revealed ongoing volcanic and seismic activity, likely the result of Jupiter’s intense gravity wracking Europa’s molten core. With heat, minerals, and liquid water, scientists now saw Europa as the most promising place in our solar system to search for extraterrestrial life.

      The complexity of a mission to Europa was unlike anything NASA engineers had encountered since the days of Apollo. Forays to other worlds had thus far only scratched the surface of those celestial bodies. Once on Europa, NASA planned to bore through at least six miles of ice in order to explore a mysterious ocean. A submersible robotic vehicle designed to plumb those hidden waters would not only have to survive a journey in the vacuum of space, but also be able to withstand a crushing pressure that, at a minimum, would equal the deepest place beneath Earth’s oceans.

      NASA’s Europa team, led by Collins and his wife, sought out the best minds in robotics, biologic testing, artificial intelligence, and deep-sea remote vehicles to help tackle the technical problems posed by the mission.The Europa Lander not only had to perform numerous complex tasks in an extreme environment but, due to the distances involved, it also had to be capable of making decisions on its own.

      Early on, Collins’s team seized on the idea of exploring Lake Vostok as a full-dress rehearsal for the mission to Europa. Exhaustive testing of various subsystems finally led to the construction of a prototype. Ice Pick incorporated all but three of the main systems to be used by the Europa Lander. The deep-space communications unit was deleted from Ice Pick, since the probe’s first stage wouldn’t be more than fifty feet from the people controlling it. While it would have been nice to have the genetic analysis module on board, the scientists at UGene were still tweaking it, and any samples retrieved from the lake would be analyzed in their laboratory afterward. The probe’s nuclear power supply – a radioisotopic thermoelectric generator – was not included, because an international treaty expressly forbade the importation of nuclear material into Antarctica.

      The wind shifted and the parhelic circles slowly faded away. Satisfied that he’d captured what he could, Collins picked up his camera and headed back to the station. He followed the thick orange umbilical line that provided power and communications to Ice Pick.

      After a quick look around the station, Collins reentered the tower air lock and closed the door. He wasted no time stripping down to his jeans and turtleneck – the station’s interior was over a hundred degrees warmer than outside. Static sparks crackled as he peeled the woolen balaclava from his head; his black hair and beard were matted down by the protective head covering.

      ‘Water?’ Nedra asked as Collins clambered up the spiral stair to the station’s main level, scratching his chin.

      ‘Oh, yeah. My mouth is drier than a camel’s ass.’

      ‘That’s not the image I want in mind the next time you kiss me.’

      Nedra filled a tall plastic glass and handed it to him. Keeping hydrated was critical in a place totally devoid of humidity, where the average annual precipitation was less than the Sahara Desert. Collins sat down beside his wife at the long workstation. Nedra’s monitor displayed the same information she hoped to receive one day, several years from now, from a spacecraft on the surface of Europa.

      ‘Status?’ Collins asked.

      ‘The sample capsules from the last mission are stowed and a new set of empties are on board the hydrobot. Batteries are at one-hundred percent charge.’

      ‘Then let’s see if we get lucky today.’

      Clinging by actuated crampons to the underside of the glacial ice sheet in the slushy upper boundary of Lake Vostok, the second stage of the Ice Pick probe waited for its next command. It had taken five days in late November for the three-foot in diameter sphere to melt its way straight down through over two miles of glacier. The cryobot liquefied the ice beneath it with the heating panels on its lower hemisphere, and, as it sank, the displaced water refroze above it to prevent contaminants from the surface from entering the hidden lake. A filament of superconducting wire imbedded in a carbon nanotube sleeve emerged from the top of the sphere like a strand of webbing from a spinneret, and ran straight up along the path of the cryobot’s descent from beneath the first stage on the surface.

      At Nedra’s command, the circular heating plate at the lower pole of the cryobot receded about a quarter-inch into the sphere, then slid away to expose an iris diaphragm.

      ‘Equalizing tube pressure,’ Nedra announced.

      A series of pressure-relief valves slowly opened to allow a flow of water from the lake to gradually enter the cylindrical chamber behind the diaphragm. Once the air inside the chamber had been evacuated and the water pressure inside made equal with that of the surrounding lake, the valves closed.

      ‘The СКАЧАТЬ