Gravity

by Tess Gerritsen

  Though this responsibility weighed heavily on his tired shoulders, Nicolai was anxious to open the hatch and float out of the air lock. To go EVA was like being reborn, the fetus emerging from that small, tight opening, the umbilical restraint dangling as one swims out into the vastness of space. Were the situation not so grave, he would be looking forward to it, would be giddily anticipating the freedom of floating in a universe without walls, the dazzling blue earth spinning beneath him.

  But the images that came to mind, as he waited with his eyes closed for the thirty minutes to pass, were not of spacewalking. What he saw instead were the faces of the dead. He imagined Discovery as she plunged from the sky. He saw the crew, strapped into their seats, bodies shaken like dolls, spines snapping, hearts exploding. Though Mission Control had not told them the details of the catastrophe, the nightmarish visions filled his head, made his heart pound, his mouth turn dry.

  “Your thirty minutes are up, guys,” came Emma’s voice over the intercom. “Time for depress.”

  Hands clammy with sweat, Nicolai opened his eyes and saw Luther start the depressurization pump. The air was being sucked out, the pressure in the crew lock slowly dropping. If there was a leak in their suits, they would now detect it.

  “A-OK?” asked Luther, checking the latches on their umbilical tethers.

  “I am ready.”

  Luther vented the crew lock atmosphere to space. Then he released the handle and pulled open the hatch.

  The last air hissed out.

  They paused for a moment, clutching the side of the hatch, staring out in awe. Then Nicolai swam out, into the blackness of space.

  “They’re coming out now,” said Emma, watching on closed-circuit TV as the two men emerged from the crew lock, umbilical tethers trailing after them. They removed tools from the storage box outside the airlock. Then, pulling themselves from handhold to handhold, they made their way toward the main truss. As they passed by the camera mounted just under the truss, Luther gave a wave.

  “You watching the show?” came his voice over the UHF audio system.

  “We see you fine on external camera,” said Griggs. “But your EMU cameras aren’t feeding in.”

  “Nicolai’s too?”

  “Neither one. We’ll try to track down the problem.”

  “Okay, well, we’re heading up onto the truss to check out the damage.”

  The two men moved out of the first camera’s range. For a moment they disappeared from view. Then Griggs said, “There they are,” and pointed to a new screen, where the space-suited men were moving toward the second camera, propelling themselves hand over hand along the top of the truss. Again they passed out of range. They were now in the blind zone of the damaged camera and could no longer be seen.

  “Getting close, guys?” asked Emma.

  “Almost—almost there,” said Luther, sounding short of breath. Slow down, she thought. Pace yourselves.

  For what seemed like an endless wait, there was only silence from the EVA crew. Emma felt her pulse quicken, her anxiety rising. The station was already crippled and starved for power. Nothing must go wrong with these repairs. If only Jack was here, she thought. Jack was a talented tinkerer who could rebuild any boat engine or cobble together a shortwave radio from junkyard scraps. In orbit, the most valuable tools are a clever pair of hands.

  “Luther?” said Griggs.

  There was no answer.

  “Nicolai? Luther? Please respond.”

  “Shit,” said Luther’s voice.

  “What is it? What do you see?” said Griggs.

  “I’m looking at the problem right now, and man, it’s a mess. The whole P-6 end of the main truss is twisted around. Discovery must’ve clipped the 2-B array and bent that end right up. Then she swung over and snapped off the S-band antennas.”

  “What do you think? Can you fix anything?”

  “The S-band’s no problem. We got an ORU for the antennas, and we’ll just replace ’em. But the port-side solar arrays—forget it. We need a whole new truss on that end.”

  “Okay.” Wearily Griggs rubbed his face. “Okay, so we’re definitely down one PVM. I guess we can deal with that. But we need the P-4 arrays reoriented, or we’re screwed.”

  There was a pause as Luther and Nicolai headed back along the main truss. Suddenly they were in camera range; Emma saw them moving slowly past in their bulky suits and enormous backpacks, like deep-sea divers moving through water. They stopped at the P-4 arrays. One of the men floated down the side of the truss and peered at the mechanism joining the enormous solar wings to the truss backbone.

  “The gimbal assembly is bent,” said Nicolai. “It cannot turn.”

  “Can you free it up?” asked Griggs.

  They heard a rapid exchange of dialogue between Luther and Nicolai. Then Luther said, “How elegant do you want this repair to be?”

  “Whatever it takes. We need the juice soon, or we’re in trouble, guys.”

  “I guess we can try the body shop approach.”

  Emma looked at Griggs. “Does that mean what I think it means?”

  It was Luther who answered the question. “We’re gonna get out a hammer and bang this sucker back into shape.”

  • • •

  He was still alive.

  Dr. Isaac Roman gazed through the viewing window at his unfortunate colleague, who was sitting in a hospital bed watching TV. Cartoons, believe it or not. The Nickelodeon channel, which the patient stared at with almost desperate concentration. He didn’t even glance at the space-suited nurse who’d come into the room to remove the untouched lunch tray.

  Roman pressed the intercom button. “How are you feeling today, Nathan?”

  Dr. Nathan Helsinger turned his startled gaze to the viewing window, and for the first time noticed that Roman was standing on the other side of the glass. “I’m fine. I’m perfectly healthy.”

  “You have no symptoms whatsoever?”

  “I told you, I’m fine.”

  Roman studied him for a moment. The man looked healthy enough, but his face was pale and tense. Scared.

  “When can I come out of isolation?” said Helsinger.

  “It’s been scarcely thirty hours.”

  “The astronauts had symptoms by eighteen hours.”

  “That was in microgravity. We don’t know what to expect here, and we can’t take chances. You know that.”

  Abruptly Helsinger turned to stare at the TV again, but not before Roman saw the flash of tears in his eyes. “It’s my daughter’s birthday today.”

  “We sent a gift in your name. Your wife was informed you couldn’t make it. That you’re on a plane to Kenya.”

  Helsinger gave a bitter laugh. “You do tie up those loose ends well, don’t you? And what if I die? What will you tell her?”

  “That it happened in Kenya.”

  “As good a place as any, I suppose.” He sighed. “So what did you get her?”

  “Your daughter? I believe it was a Dr. Barbie.”

  “That’s exactly what she wanted. How did you know?” Roman’s cell phone rang. “I’ll check back on you later,” he said, then turned from the window to answer the phone.

  “Dr. Roman, this is Carlos. We’ve got some of the DNA results. You’d better come up and see this.”

  “I’m on my way.”

  He found Dr. Carlos Mixtal sitting in front of the lab computer. Data was scrolling down the monitor in a continuous stream:

  The data was made up of only four letters, G, T, A, and C. It was a nucleotide sequence, and each of the letters represented the building blocks that make up DNA, the genetic blueprint for all living organisms.

  Carlos turned at the sound of Roman’s footsteps, and the expression on his face was unmistakable. Carlos looked scared. Just like Helsinger, Roman thought. Everyone is scared.

  Roman sat down beside him. “Is that it?” he asked, pointing to the screen.

  “This is from the organism infecting Kenichi Hirai. We took it
from the remains that we were able to…scrape from the walls of Discovery.”

  Remains was the appropriate word for what was left of Hirai’s body. Ragged clumps of tissue, splattered throughout the walls of the orbiter. “Most of the DNA remains unidentifiable. We have no idea what it codes for. But this particular sequence, here on the screen, we can identify. It’s the gene for coenzyme F420.”

  “Which is?”

  “An enzyme specific to the Archaeon domain.”

  Roman sat back, feeling faintly nauseated. “So it’s confirmed,” he murmured.

  “Yes. The organism definitely has Archaeon DNA.” Carlos paused. “I’m afraid there’s bad news.”

  “What do you mean, ‘bad news’? Isn’t this bad enough?”

  Carlos tapped on the keyboard and the nucleotide sequence scrolled to a different segment. “This is another gene cluster we found. I thought at first it had to be a mistake, but I’ve since confirmed it. It’s a match with Rana pipiens. The northern leopard frog.”

  “What?”

  “That’s right. Lord knows how it picked up frog genes. Now here’s where it gets really scary.” Carlos scrolled to yet another segment of the genome. “Another identifiable cluster,” he said.

  Roman felt a chill creeping up his spine. “And what are these genes?”

  “This DNA is specific to Mus musculis. The common mouse.”

  Roman stared at him. “That’s impossible.”

  “I’ve confirmed it. This life-form has somehow incorporated mammalian DNA into its genome. It’s added new enzymatic capabilities. It’s changing. Evolving.”

  Into what? Roman wondered.

  “There’s more.” Again Carlos tapped on the keyboard, and a new sequence of nucleotide bases scrolled onto the monitor. “This cluster is not of Archaeon origin, either.”

  “What is this? More mouse DNA?”

  “No. This part is human.”

  The chill shot all the way up Roman’s spine. The hairs on the back of his neck were bristling. Numbly he reached for the telephone.

  “Connect me to the White House,” he said. “I need to speak to Jared Profitt.”

  His call was answered on the second ring. “This is Profitt.”

  “We’ve analyzed the DNA,” said Roman.

  “And?”

  “The situation is worse than we thought.”

  EIGHTEEN

  Nicolai paused to rest, his arms trembling from fatigue. After months of living in space, his body had grown weak and unaccustomed to physical labor. In microgravity there is no heavy lifting and little need to exert one’s muscles. In the last five hours, he and Luther had worked nonstop, had repaired the S-band antennas, had dismantled and reassembled the gimbal. Now he was exhausted. Just the extra effort of bending his arms in the turgid EVA suit made simple tasks difficult.

  Working in the suit was an ordeal in itself. To insulate the human body from extreme temperatures ranging from 250 to 250 degrees Fahrenheit and to maintain pressure against the vacuum of space, the suit was constructed of multiple layers of aluminized Mylar insulation, nylon ripstop, an Ortho-fabric cover, and a pressure-garment bladder. Beneath the suit, an astronaut wore an undergarment laced with water-cooling tubes. He also had to wear a life-support backpack containing water, oxygen, self-rescue jet pack, and radio equipment. In essence, the EVA suit was a personal spacecraft, bulky and difficult to maneuver in, and just the act of tightening a screw required strength and concentration.

  The work had exhausted Nicolai. His hands were cramping in the clumsy space suit gloves, and he was sweating.

  He was also hungry.

  He took a sip of water from the mouthpiece mounted inside his suit and released a heavy sigh. Though the water tasted strange, almost fishy, he thought nothing of it. Everything tasted strange in microgravity. He took another sip and felt wetness splash onto his jaw. He could not reach into his helmet to brush it away, so he ignored it and gazed down at the earth. That sudden glimpse of it, spread out in breathtaking glory beneath him, made him feel a little dizzy, a little nauseated. He closed his eyes, waiting for the feeling to pass. It was motion sickness, nothing more; it often happened when you unexpectedly caught sight of earth. As his stomach settled, he became aware of a new sensation: The spilled water was now trickling up his cheek. He twitched his face, trying to shake off the droplet, but it continued to slide across his skin.

  But I am in microgravity, where there is no up or down. Water should not be trickling at all.

  He began to shake his head, tapped his gloved hand on his helmet.

  Still he felt the droplet moving up his face, tracing a wet line up his jaw. Toward his ear. It had reached the edge of his comm-assembly cap now. Surely the fabric would soak up the moisture, would prevent it from trickling further…

  All at once his body went rigid. The wetness had slid beneath the edge of the cap. It was now squirming toward his ear. Not a droplet of water, not a stray trickle, but something that moved with purpose. Something alive.

  He thrashed left, then right, trying to dislodge it. He banged hard on his helmet. And still he felt it moving, sliding under his comm assembly.

  He caught dizzying glimpses of earth, then black space, then earth again, as he flailed and twisted around in a frantic dance.

  The wetness slithered into his ear.

  “Nicolai? Nicolai, please respond!” said Emma, watching him on the TV monitor. He was turning around and around, gloved hands battering frantically at his helmet. “Luther, he looks like he’s having a seizure!”

  Luther appeared on camera, moving quickly to assist his EVA partner. Nicolai kept thrashing, shaking his head back and forth. Emma could hear them on UHF, Luther asking frantically, “What is it, what is it?”

  “My ear—It is in my ear—”

  “Pain? Does your ear hurt? Look at me!”

  Nicolai slapped his helmet again. “It’s going deeper!” he screamed. “Get it out! Get it out!”

  “What’s wrong with him?” cried Emma.

  “I don’t know! Jesus, he’s panicking—”

  “He’s getting too close to the tool stanchion. Get him away before he damages his suit!”

  On the TV monitor, Luther grabbed his partner by the arm. “Come on, Nicolai! We’re going back in the air lock.”

  Suddenly Nicolai clutched at his helmet, as though to rip it off.

  “No! Don’t!” screamed Luther, clutching at both of his partner’s arms in a desperate attempt to restrain him. The men thrashed together, umbilical tethers winding, tangling around them.

  Griggs and Diana had joined Emma at the TV monitor, and the three of them watched in horror as the drama unfolded outside the station.

  “Luther, the tool stanchion!” said Griggs. “Watch your suits!”

  Even as he said it, Nicolai suddenly and violently twisted in Luther’s grasp. His helmet slammed into the tool stanchion. A fine stream of what looked like white mist suddenly spurted out of his faceplate.

  “Luther!” cried Emma. “Check his helmet! Check his helmet!”

  Luther stared at Nicolai’s faceplate. “Shit, he’s got a crack!” he yelled. “I can see air leaking out! He’s decompressing!”

  “Tap his emergency O2 and get him in now!”

  Luther reached over and flipped the emergency oxygen supply switch on Nicolai’s suit. The extra airflow might keep the suit inflated long enough for Nicolai to make it back alive. Still struggling to keep his partner under control, Luther began to haul him toward the air lock.

  “Hurry,” murmured Griggs. “Jesus, hurry.”

  It took precious minutes for Luther to drag his partner into the crew lock, for the hatch to be closed and the atmosphere repressurized. They didn’t wait for the usual air-lock integrity check, but pumped the pressure straight up to one atmosphere.

  The hatch swung open, and Emma dove through into the equipment lock.

  Luther had already removed Nicolai’s helmet and was frantically trying to pull
him out of the upper torso shell. Working together, they wriggled a struggling Nicolai out of the rest of his EVA suit. Emma and Griggs dragged him through the station and into the RSM, where there was full power and light. He was screaming all the way, clawing at the left side of his comm-assembly cap. Both eyes were swollen shut, the lids ballooned out. She touched his cheeks and felt crepitus—air trapped in the subcutaneous tissues from the decompression. A line of spittle glistened on his jaw.

  “Nicolai, calm down!” said Emma. “You’re all right, do you hear me? You’ll be all right!”

  He shrieked and yanked off the comm cap. It went flying away.

  “Help me get him onto the board!” said Emma.

  It took all hands to set up the medical restraint board, strip off Nicolai’s ventilation long johns, and strap him down. They had him fully restrained now. Even as Emma checked his heart and lungs and examined his abdomen, he continued to whimper and rock his head from side to side.

  “It’s his ear,” said Luther. He had shed his bulky EVA suit and was staring wide-eyed at the tormented Nicolai. “He said there was something in his ear.”

  Emma looked closer at Nicolai’s face. At the line of spittle that traced from his chin, up the curve of his left jaw. To his ear. A drop of moisture was smeared on the pinna.

  She turned on the battery-powered otoscope and inserted the earpiece into Nicolai’s canal.

  The first thing she saw was blood. A bright drop of it, glistening in the otoscope’s light. Then she focused on the eardrum.

  It was perforated. Instead of the gleam of the tympanic membrane, she saw a black and gaping hole. Barotrauma was her first thought. Had the sudden decompression blown out his eardrum? She checked the other eardrum, but it was intact.

  Puzzled, she turned off the otoscope and looked at Luther. “What happened out there?”

  “I don’t know. We were both taking a breather. Resting up before we brought the tools back in. One minute he’s fine, the next minute he’s panicking.”