As they drew closer, they discerned a fissure running roughly down the middle of the asteroid’s flat surface. They weren’t able to tell how deep it went, but it was clear that something had caused the massive rock to nearly cleave into two pieces. Near the limb of the asteroid farthest from their present position there was another crack that looked more like something had taken a bite off the edge of the giant cookie than it did a missing chunk of asteroid.
“I’m bettin’ that missing chunk over there is what hit us a month ago.” Paul pointed at the image on the screen as he whistled. “Looks less solid there according to the lidar.”
“I suspect you are correct, Paul. But until we take the radar data and reconstruct the debris field and then compare it to the surface of the asteroid we will not know for certain,” Hui replied.
“Leave it for the Ph.D. students back at university,” Mikhail Rykov added.
“Right, whatever. I’m just glad Asteroid Ores’ tether system worked to despin this monster,” said Gesling. “Otherwise, this mission would be way more complicated.”
“And dangerous,” Rykov said.
“Yes.” Hui nodded in agreement. “We didn’t believe it would work. My country has had engineers looking at the asteroid tumble problems for years. They looked at using tethers to remove the angular momentum and then promptly put it near the bottom of the list calling it ‘too risky.’”
“Us too. We always concluded that the tethers would break. That’s why we baselined electric propulsion for both the propulsion system to move the rock and to despin it,” remarked Rykov.
“I guess this just goes to show that sometimes simpler is better,” Paul commented.
“Look! There! I can see the EP module,” Hui almost shouted.
Just coming into view as the habitat passed the asteroid’s flat surface on its first slow flyby was the propulsion module containing the malfunctioning electric propulsion system. As far as he could tell there was no light coming from the exhaust nozzle. There was no glow of plasma. There were no blinking running lights. There was basically no sign of anything functioning. But they were still a bit far off to see much detail.
“I see it, but we’re too far away to see if there is any damage—if there’s anything to see. It could be an internal problem. I need to get into it to see what’s wrong,” Rykov said.
“One more pass and then I think we can bring the ship in close enough to dock. How far away do you want me to take her before you try the harpoon?” Paul asked Hui as he turned to look at Mikhail, who was floating behind and to the left of him. He wished the Russian would put his butt in a seat. The floating around was seriously distracting. Paul was more used to sitting in a seat and flying. That made sense. How the hell could anyone be able to reach all the buttons and switches and controls while floating about?
“I should be able to set the harpoon to within a hundred meters of the propulsion module. I don’t want to risk having the harpoon miss and cause more damage to it,” Hui replied. Paul turned back and looked at her strapped into the seat to his right.
“A hundred meters is pretty close. I can do that,” he reassured her. “How many times were you able to rehearse harpooning?”
“Not enough. And they were all VR simulations. There wasn’t enough time to get any real experience on the ground, not that it would have done any good. We’re so used to gravity that we automatically adjust for its effects when we shoot arrows or guns, or throw balls for that matter. We aim high, allowing for the ball or bullet to fall while in flight. Out here, the gravity will be negligible so it’ll be totally different. The simulator is probably better.”
Two hours later, Gesling had adjusted the ship’s velocity and orientation so that it was relatively stationary above the edge of the rock. Even though they were moving through space at about seventeen kilometers per second relative to the Earth, no one would know it from looking out the windows of the habitat. With no objects moving past and only the dark emptiness of space providing background, there was no reference to show motion and it looked like they and the rest of the universe were at rest.
Hui was velcroed in front of the laptop computer station and monitor that controlled the harpoon that would spear the asteroid. She’d been there with the VR goggles strapped on her face for the past hour practicing with the harpoon gun simulation now that they had the actual visual map of the real asteroid to use in the simulation. She wanted to practice with as real a target as possible since she only had two chances to make it work. They were only able to outfit the ship with two harpoon guns and winches and if she wasn’t able to make one or the other stick tightly enough to reel the ship in and keep it in place, then they’d have to risk stationkeeping by constantly adjusting the ship’s position with the attitude control thrusters to repair the broken divert system, dramatically increasing the risk to the crew.
“Hui, are you ready?” asked Gesling.
“Yes. I’ve targeted a spot that looks like the harpoon should be able to penetrate. From what I can tell, the part of the rock I’ve targeted is integral with the main body of the overall rock and not a clinger.”
“A clinger?” asked Rykov.
“A smaller rock that is barely gravitationally bound to the main rock,” Paul explained to the Russian.
“Ah yes,” Rykov muttered something that sounded like “ahh-stah-va-sir veer-a-nim.” Paul guessed it was a Russian translation for “clinger.”
“If we try to pull this ship into a rock that’s not part of or connected firmly to the main asteroid,” Hui continued. “Then we’ll pull a small boulder toward the ship instead of the ship toward the rock. That would be bad and we won’t know until we start the winch.”
“And if it is a rock that pulls loose? Won’t it be coming right toward us?”
“Yeah. That’s why I’ll be watching with one hand on the thrusters and the other on the button that will cut the cable to the harpoon. If a rock starts coming toward us, I need to be able to get us out of the way quickly.”
“That’s great. I feel so much better.” Rykov didn’t sound convinced to either Gesling or Tian. “Bozhe moi, don’t mind me. I think I’ll go sit by the nuclear reactor where it is safe.”
“Here we go,” Hui said as she tapped a series of commands into the keyboard.
The crew heard a low frequency thump as the rocket-powered harpoon fired from what looked like a cannon mounted just below the cylindrical hull of the habitat. Attached in Earth orbit by astronauts during one of the many EVAs required to assemble the overall deep space vehicle, the harpoon canister did look a cannon but functioned more like a rocket-propelled grenade launcher—one that fired a depleted uranium tipped tungsten spike propelled by a fast-burning solid rocket motor. Derived from the latest generation army anti-mortar intercept rockets meant to protect ground troops in combat from enemy mortar rounds, the harpoon sped toward the rock accelerating at about thirty-two gees. But since it was a rocket and not a cannon, there was very little recoil to the larger spacecraft.
Gesling and Rykov watched the impact through the window while Tian was still in her VR goggles. Paul suspected she was using the camera mounted on the harpoon, riding with the projectile until the moment of impact.
When the harpoon hit, a shaped charge in the nosecone fired, forcing the barbed grapple contained within it further into the rock. If it worked as designed, the cable would be firmly embedded in the asteroid. As far as Paul could tell, the harpoon hit the asteroid and kicked up small shards of rock and debris that flew out into space within roughly a forty-five-degree angle from the vertical. The debris cloud expanded outward from the asteroid, creating a plume that in the sunlight flickered like fireflies. He kept his hands near the thruster controls, just in case he had to perform a quick maneuver to avoid any debris.
“I didn’t think about the debris. Will any of it hit us?” Rykov asked.
“It shouldn’t. The harpoon was designed to not kick debris straight back at us. And the shaped charge
in the nosecone concentrated most of the force produced by the explosion into setting the grapple,” Hui replied. “Besides, the relative velocity would be very small compared to what the multi-layer insulation blankets the ship is wrapped in are designed to stop.”
“I guess I’m used to the Moon. Even though the gravity there is only one-sixth gee, rocks blown into the sky will still fall back down. We’ve been mining there for a few years now and none of our explosions looked like that one,” Rykov said.
“If any of it were going to hit us, it would have done so by now,” Gesling said as he entered a few more commands into the console before him. “As far as the lidar and ground penetrating radar is concerned we’re locked in.”
“Let’s hope so,” Rykov agreed nervously.
“I’m starting the winch,” he added. Hui pulled the goggles off and nodded to him that she was good to go.
Hui and Mikhail both looked up as the vibration from the winch starting produced a low rumbling sound throughout the habitat. The habitat briefly jolted and then the vibration stopped.
“We’re connected. I pulled us in a few meters to check the strength of the connection—making sure the grapple held—and it all appears to be fine. I’ll slowly pull us in to within about fifty meters of the surface. Then we can relax and sleep. Mikhail, tomorrow will be your day. All I have to do is sit up here and watch.”
* * *
Two hours later, they were each in their personal spaces zipping themselves into their sleeping bags along the outside wall of the habitat with their heads toward what they all agreed would be the ceiling. The nightly banter between them, even after several months in space, often sounded like that of kids in a college dormitory.
“Mikhail, we were thrown together so quickly for this mission that I never had a chance to ask you how you picked up your electric propulsion expertise. You spent over seven months on the ISS and commanded three tours at your Moon base, not something a typical electrical engineer has on his resume.”
“I studied at the Moscow Aviation Institute where I worked with the chief architect of the Coeus Titan sample return mission. I actually designed the electric thrusters used to bring back the samples. Shortly after the hardware was delivered for launch, I joined the Russian Air Force with the goal of becoming an astronaut. By the time the Coeus reached Titan, I was in astronaut training and when the samples made it back to Earth I had been on the ISS for months. Before the samples were fully analyzed I was on the Moon for my first turn of duty.”
“That’s an impressive career path, Mikhail,” Hui said.
“Fifteen years. That’s how long it took Coeus to fly from Earth to Titan and back again. That’s also how long it took me from the time I joined the air force until I was walking on the Moon. We mustn’t forget how close the Moon is and how truly far away the planets are.”
“Anyone looking at our flight path would have to agree with you,” Gesling replied.
“Three months is a long time to be traveling, isn’t it?” Hui said.
“I’m just glad we’re not at each other’s throats by now. Our market research for the hotel shows that some of the crews that spent this much time together on the International Space Station weren’t talking to each other at this point,” said Gesling.
“It is better than fifteen years,” added Rykov. “And I can tell you that after seven months on the ISS that, well, uh, tempers often flare up.”
“Paul, how is your wife?” Hui, asked. Paul couldn’t see her through his privacy curtain, but he was sure she had asked with sincere interest.
“No change. The report today was the same as it was yesterday and the day before that. Her brain is functioning, they believe she is dreaming. But she’s totally unresponsive.” Paul thought about her dreaming and in some way imagined that she had managed to connect with him in his dreams since he’d been out in deep space. He knew that was just a fantasy, but sometimes it was good to believe in a fantasy, at least for a little while.
“Don’t let that dampen the mood. I try to be an optimist and at least her condition hasn’t worsened. If I’d remained at home, I’d be a basket case worrying that you guys were going to screw it all up and let this rock kill half a billion people.” Paul did his best to be the upbeat commander.
“That shall not happen, comrade,” Mikhail said. Paul knew he probably never said “comrade” in his daily life until he became the only Russian on the mission. It had become sort of a mark of national pride with Mikhail so he had humorously hammed it up. So much so that it had become an unconscious habit in his speech pattern. “We will stop the damned rock.”
“I agree. It shall not hit the Earth,” said Hui.
Within only a few minutes, both Hui and Mikhail were asleep, leaving Paul to ponder his own thoughts as sleep eluded him. Paul had seen her sleeping with her cube unzipped and he imagined how she must look now with her arms outside of the sleeping bag’s netting. Hui seemed to prefer her arms floating freely in front of her as she slept. Paul imagined that she looked like a sleepwalking zombie from some hundred-year-old Hollywood movie. He smiled. He had no clue how Rykov slept and had no desire to interrupt him.
The hum of the fans used to keep the air recirculating throughout the cabin usually lulled Paul into sleep, but not tonight. His mind was racing through what the next few days would entail. He always felt this way the day before a big flight or mission event. All the times before it was usually only himself or possibly a tourist or two that would die if he screwed up. This time millions of people, and maybe even his wife, were at risk. He knew he couldn’t screw up.
First, they had to get Rykov down to the surface to examine the electric propulsion thruster that was malfunctioning. There were not enough self-diagnostics built into the spacecraft for them to ascertain its health status—a very piss-poor design by the mining company, Paul thought. The only way to figure out what was wrong with it was to go out there and dig into it. That is why they had brought the expert on spacecraft electric propulsion, Mikhail Rykov. If there were papers written in rocket and propulsion journals that didn’t reference his work you could just skip them and look for the ones that did.
Rykov was, in this case, the best man for the job. That was why he was out there with them. He had to decide whether or not the electric propulsion engine could be repaired or if he would have to emplace the spare they brought with them. Once they had an engine that was working, the flight plan called for them to loiter at the rock for a few days to make sure the systems were working as they should before performing the burn that would bring them home safely ahead of the rock. His mind was racing through all of the things that could go wrong and how they would respond.
Dammit. I hate it when this happens. How do these guys fall asleep so quickly?
It took the better part of an hour, but Gesling eventually fell asleep.
CHAPTER 22
The explosion happened two hours and seventeen minutes into the spacewalk. Rykov and Tian had long since exited the airlock and used their tether-free Autonomous Maneuvering Units, or AMUs, to fly themselves “down” to the broken electric thrusters on the surface of Sutter’s Mill. They had just opened the casing containing the thruster to begin repairing the thruster when all hell broke loose in the habitat.
At first Paul didn’t know what was happening. The pop he heard wasn’t terribly loud, but it shook the entire length of the habitat, causing it to vibrate like a person’s stomach might standing next to the snare drum in a marching band. Then several of the status lights on the control panel began to blink red and buzzers sounded throughout the Command Capsule.
“What the hell?” muttered Gesling as he pushed himself through the air and over to the control panel to see just what the hell was going on.
The vibration continued and all he could tell from the instrumentation was that attitude control thruster number four had failed. He again glanced around the habitat’s interior and his eyes settled on the window facing the asteroid to which they
were anchored. It was starting to rotate. Rather, he was starting to rotate relative to the asteroid and that shouldn’t be happening. The ship was a behemoth and it took a lot to get her rotating. Not to mention accelerating.
He timed how long it took for the image of the asteroid to come back into the same relative position where it started and took a mental note. In the meantime, he was quickly running through the checklist necessary to run a diagnostic of the propulsion system to figure out what was happening. Precious seconds went by with no useful information coming from the instrumentation. He again looked at the window and timed how long it took the ship to rotate three hundred sixty degrees. It took three fewer seconds than the first one he measured. Whatever had gone wrong was still happening and his spin was accelerating.
“Mikhail, Hui, listen up. Something’s happened up here and I’ve lost attitude control. The ship is spinning. Can you see anything from where you are?”
“My God, we hadn’t noticed. We were so intent on the thruster that we hadn’t looked up. Yes, you are spinning and you’ve got slack tether,” replied Mikhail.
“And I think I see number four thruster firing. That must be what’s causing the spin. You’ve got to shut it off,” added Hui.
“I knew there was a problem with number four but I didn’t realize it was stuck on. All I can tell from in here is that it failed.”
“You’d better do something pretty quick. The tether is getting more slack. You’re not only spinning, but you’re thrusting yourself closer to the surface with every rotation. Pretty soon you’ll tangle in the tether and rip off the communications antenna or one of the radiator arrays.”
Inside the habitat, the altimeter alarm sounded. Gesling was spiraling in toward the asteroid and at an accelerating rate. He had to do something to stop the descent and the spin or the ship would be seriously damaged.
On to the Asteroid Page 13