This was a dangerous environment for machines as well, particularly the kind of fragile silicon-based electrically powered contraptions flung by humans into deep space. Already hardened against the harsh electromagnetic environment, flying anywhere near Jupiter demanded an extra measure of protection.
It was impossible to protect against everything, which became most apparent when designers needed to trim mass. Encase the vehicle in enough dense metals like lead and it’d be fine, it just would be too heavy to send anywhere. Thus a few millimeters of aluminum and Mylar foil was all that stood between Cygnus’ electronic brain and the radioactive hell of Jupiter’s magnetosphere. This would have been more than enough, had an unusually energetic Sun not charged up the field to a precarious degree.
While unwelcome, it wasn’t unexpected either. It was for this very reason that Cygnus’ computer brain was programmed with enough common sense to know when it needed to take extraordinary measures to protect itself. And so the massive spike in EM radiation Cygnus detected as it crossed Jupiter’s magnetopause led it to tuck its electronic tail and hide.
In spaceflight parlance this was called “Safe Mode,” wherein the ship shut down and cut itself off from outside influence lest another surge confuse the computers enough to order it into some self-destructive behavior.
To protect itself, Cygnus went dark. Its small reactor only spared enough current to keep core memory from vanishing and to power its rendezvous beacons. This also meant keeping its attitude and guidance routines shut down: Star trackers, control jets and orientation gyros were cut off to protect the craft from becoming hopelessly disoriented.
This meant Jupiter’s gravity was able to fully assert itself, pulling on Cygnus undeterred by the spacecraft’s stabilizing flywheels. Almost the length of a football field, the stack of cargo modules and propellant tanks was drawn into a tumble as it fought a natural tendency to align itself with the gravity gradient. Imperceptible at first, it began increasing with each revolution.
It took an hour for this information to make it back to Cygnus’ controllers in Pasadena’s Jet Propulsion Lab. By the time JPL finished their diagnostics and attempted reboots, it was another hour before they sounded the alarm in Houston. It would be another hour before this information could be relayed to Magellan.
♦ ♦ ♦
Cygnus had been a blip on their radar long before it showed up in their windows. The cargo ship shone in the distance, its strobe beacon distinguishing it from the other bodies orbiting Jupiter. “Thar she blows,” Jack called out from the control deck. “Does that mean I win the pot?”
“Didn’t know we were taking bets,” Traci said over her shoulder, watching their rendezvous from the copilot’s station.
“You remember: First one to get eyeballs on it wins everybody else’s coffee ration for the month. I’m pretty sure we were all in on it.”
“Nice try,” she snorted. “Wouldn’t have anything to do with yours being used up?”
“Pure coincidence. More evidence of the perfect symmetry of the universe. You don’t need all that caffeine anyway.”
“Speak for yourself,” Roy grumbled, his mug trailing an aroma of Colombian dark roast as he shuffled past on his way to the command pilot’s station.
“You’re killing me here,” Jack groaned. “What I wouldn’t give for—”
“For what?” Noelle said as she buckled in next to him, pushing over a sealed mug of hot black liquid.
Jack perked up with the first luxurious sip. “Bless you, dear lady.”
“We need everyone in top form, and it wouldn’t do for our flight engineer to be underperforming just because he can’t control his personal habits,” she scolded him. “I’m being practical.”
Even Roy howled at that one as Jack’s shoulders sagged. “Harsh. But true. And seriously, thanks.”
Noelle patted his arm. “Don’t mention it,” she said, then leaned in and whispered. “Besides, that came out of Roy’s rations.”
Owen Harriman had been pacing behind his desk on Manager’s Row for what couldn’t have been more than a few minutes, until the mission clocks caught his eye. He looked back down at his watch in consternation: Had it really been an hour? A quick glance around the control room revealed nothing but the backs of controllers hunched over their consoles. He hoped his new nervous habit would remain unnoticed by the others.
“You must sit,” ordered a gruff voice behind him. Anatoly Rhyzov pulled Owen’s empty chair back from his console.
Owen slumped into it, almost rolling into the credenza behind them. “Sorry. Hard to control my nerves.”
“That is your business, not mine,” Rhyzov said dismissively. He nodded toward the wall screens at the front of the room. “You were blocking my view.”
“Here I thought you were concerned about me.”
Rhyzov waved him away in a “no worries” gesture that Owen had gotten used to seeing. “Everyone copes in own way,” he said, pointing at the GNC desk. “Your guidance controller has been gripping rail beside his console so long his hand is turning purple.”
“That’s why we kept those handles. They used to be for swapping out balky displays in a hurry. Turns out it keeps the flight controllers sane.”
“We did same. Is stressful, this work. Much to watch with little to do.” He tapped his forehead. “All work is up here.”
Owen tapped his stomach in return. “And it’s felt down here.” It was too easy to forget that his Russian mentor had endured his own trials in the hot seat. They would’ve been about the same age, too. What might they be doing in here when he reached Anatoly’s age?
“Our control room was same. Used to directing cosmonauts. Not used to waiting for them.”
“This was easier when everything was working normally,” Owen admitted. The light delay was close to an hour each way and the mental gymnastics threatened to consume him. Everything happening in here had already happened out there. It was maddening for a room full of people conditioned to working under extreme pressure to now feel so impotent. They were being forced to take in data, analyze trends, and predict what might happen in the next hour instead of making snap decisions right now. The farther Magellan traveled, the farther out they’d be forced to predict based on information that was old and growing older each day. The many permutations of possible outcomes forced them to become more reliant on an AI network that mirrored the one aboard ship.
On top of that, the masters of problem solving were dependent on their cohorts at JPL who were right now consumed with trying to recover their tumbling resupply vessel. Normal mission rules would demand a wave-off, aborting the rendezvous and defaulting to “Plan B” using Jupiter’s gravity to bend their trajectory back toward Earth.
In reality that would’ve been “Plan A” on any other mission, but a normal mission also wouldn’t have light delays of over an hour in each direction. By the time word reached Magellan, chances were good the crew was seeing it for themselves and taking matters into their own hands.
“It’s like we’re team owners at a horse race,” Owen complained. “We’ve put everything we have into our prize steed, and now we have to stand back and find out if the trainer and jockey actually know what they’re doing.”
“You are much too hard on yourself,” Rhyzov said with a knowing look. “You have even less control than that.”
Owen was afraid to ask. “What do you mean by that?”
“Racetrack is also made by man. Natural materials but still groomed by man. Space is raw nature. Untamed and untamable. Has its own rules and does not give up its secrets easily.”
“And all that fancy math we depend on?”
“Gets your horse onto track. Does not guarantee it will win. Or finish.”
Owen wanted to sink into his chair when he noticed Flight glaring at them. “Gentlemen, we have a problem to work here and you’re becoming a distraction to my flight controllers. Please take the philosophical discussions outside.”
Roy�
�s crew would either figure it out, or they wouldn’t. Meanwhile, the team in Houston was getting their first hard lesson at being interested spectators.
With no time to leave his station for the telescope down on the workshop deck, Roy strained to tease out more detail from the cameras tracking Cygnus. “Strobes look weird.”
“Weird how?” Traci asked.
“Like they’re out of synch,” Roy said, though it was hard to tell this far out. “Any updates from Houston or JPL?”
“Negative,” Jack said. “We’re about due for one, though.”
Roy frowned and reached for the binoculars he kept in a compartment behind his seat. He turned to Traci. “Has the remote pinged you yet?”
“Negative. Intermittent carrier signal, but we’re also close to max range. Could be magnetic interference.”
Roy loosened his straps and pressed against the window. Jupiter loomed in the distance, days away but still close enough that its glow outshone all but the brightest stars. Well over a dozen kilometers ahead, there was no mistaking the cargo ship’s flashing beacon among the steady lights of Jupiter’s moons hanging in the black. “Lights down, please.”
He kept his eyes closed as Traci killed the cabin lighting, relaxing his vision. When he returned to his perch, he shifted his focus to an empty point in space next to Cygnus. This allowed his eyes to better perceive light and confirmed what he’d come to suspect. “It’s too bright,” he said. “Irregular.”
“It’s not the ship’s beacon,” Traci agreed. “Oh boy.” If it wasn’t the spacecraft’s beacon, that meant it had to be the spacecraft itself. Its metal framework and radiator panels and fuel tanks reflected the sunlight at irregular intervals as the stack tumbled through space.
The warning message arrived from Houston just in time to confirm Roy’s suspicions. His muffled curse put the exclamation point on the brewing trouble. He turned to Traci. “Can you do anything with the remote?”
She tapped a few commands into the controls by her flight station, trying to take over for Cygnus’ now-dormant guidance package. “No joy,” she said sourly. “It’s stuck on stupid.”
Roy pushed back down into his seat and updated his rendezvous cues. At their current rate it would be another hour before they were close enough to see for certain—about the same time it would take to get it in range for the remote. Traci might be able to null its rates to where it was safe enough for Jack to grab with the arm, but bringing them that close to a tumbling spacecraft was unacceptably dangerous.
He scratched at his chin. They could do something, or nothing. And nothing wasn’t acceptable.
“Jack, is Puffy still go on standby?”
He swiped over one of his screens and scrolled down its menu. “Comm is good. So is electrical. Fuel cells running at thirty-percent output, main bus A and B both at twenty-four volts. Controls and life support diagnostics came back nominal. All the important stuff is hibernating on standby.”
“How long to get through the full power-up checklist?”
It took him a second to get past his surprise and pick up on Roy’s question. Was he really going for it? “The big item’s aligning the guidance platform. That’s about twenty minutes with cross-checks. All that’s left is to charge the prop tanks and warm up the thrusters.”
“Do a propellant transfer from our tanks, too. I want full authority in RCS and OMS.”
Traci raised her hand. “Question, boss. Where are we—”
“We’re not going anywhere,” Roy said. He paused to consider his next words. “At least not all of us. You and Noelle have to stay here and keep flying the ship. Jack and I are going after Cygnus.”
10
Mission Day 34
Velocity 320,485 m/s (716,904 mph)
Acceleration 0.0 m/s2 (0g)
Jack swallowed hard. “We are?”
“I need you to manage our rendezvous while I fly the spacecraft. If anything happens to us, Traci will take over command while Noelle launches her probes.”
The ensuing silence from the others fell over Roy like a cloud. He could sense their eyes boring holes into his back. Roy unlocked his seat and turned to find them expectantly watching him. “Don’t tell me you’re surprised,” he said. “We trained for this scenario.”
“I don’t recall our target being out of control in the sim,” Jack said. “Not this close to rendezvous.”
“You’ve recovered tumbling satellites before.”
“But we don’t know what caused it go into safe mode yet. If that thing starts thrusting at random again . . . ”
“It won’t.”
“How do you—”
Roy held up a finger to cut him off. He pulled up Cygnus’ telemetry on a multifunction display between the pilots’ stations. Guided by little more than intuition, he scrolled down through the event logs until he found what he was looking for. “Here. See? Something tripped the RCS electrical bus and it started firing thrusters at random.” He scrolled down another second, then two more. “Gyros tried to compensate but the angular rates were too high. When the antennas lost contact with home, they went into gimbal lock before the master computer could even try switching guidance over to the secondary platform. When that happened . . . ”
“The guidance platform went into safe mode,” Jack said, working through his own mental picture. “That would be consistent with an EM surge.”
“Correct. Cygnus doesn’t have as many protections as we do. Jupiter’s radiation belt is playing hell with it and the computers finally had enough. They shut down before they got fried.”
“So here we are,” Traci grumbled. She didn’t have to say what that meant for the mission. What had to come next was harder. “You wouldn’t be nursing a case of ‘go fever,’ would you?”
“Maybe,” Roy admitted, tapping his fingers on his armrest. “I’d be lying if I said otherwise. We came all this way to do what? Throw some tungsten darts at Europan icebergs and snap a few pretty pictures of Jupiter’s clouds? Do you guys want to go home yet?”
The scowl that flashed across Noelle’s face could have melted those icebergs. “No, but I also prefer to have my husband alive. We still haven’t crossed the most energetic radiation zone.”
Jack consulted a plot of their trajectory and overlaid it on a diagram of Jupiter’s magnetosphere. “Six hours,” he said. “Assuming we undock in two, that gives us four hours before we have to get back inside. And no EVAs,” he insisted. It was the closest he’d allow himself to outright insubordination, but it would also be his butt in the suit.
“Wouldn’t ask that of anyone here,” Roy said. “Not even you, Jack.”
“What are the rates?” Noelle asked. Already skeptical by nature, having her husband as part of the equation made her especially so.
Roy scrolled back to the last time stamp. “Rolling at two degrees per second. Yaw’s about half that. Pitch is close to null.”
“So one complete rotation roughly every minute and a half, spinning at three minutes. It’ll be sporty,” Jack said. “So what’s the plan?”
Roy scratched again at his chin stubble as he thought. “Roll is easy once we’re aligned with its axis. Matching yaw is going to take some finesse. We’ll have to fly a tight circle around it and keep shortening the radius until we match rates. If we can’t, we scrub. Call that Gate One. If we manage to dock and I can’t null rates, we scrub. That’s Gate Two.”
Traci still needed convincing. “It’s going to burn a lot of gas, even before you start trying to stop that tumbling. Ever done anything like that?”
“Not even close,” he admitted. “But I can figure it out.”
Noelle rolled her eyes. “Pilot bravado,” she sighed. “You really don’t have to do that, love.”
“Yes I do,” Roy said, “unless we want this to be the end of it.” It went without saying that it would have to be a unanimous decision.
“No, you don’t. That’s not what I meant. All you have to do is match its yaw rate. We can do t
he rest from here.”
That puzzled Roy for a second. “The remote?”
“The remote,” Noelle said. “Match Cygnus’ spin. You’ll still be close enough to us for your VHF datalink to keep lock so I can relay the signal. If you can stay aligned with its antenna, we can reboot it from here and take control.”
It hadn’t been intentional that Roy and Jack had separated from Magellan and were underway by the time their plans were received in Houston, but it helped. Given the time constraints, Roy couldn’t wait for the inevitable denial from Mission Control. Even if they could have waited, Houston’s misgivings might as well have been cast into thin air.
Cygnus, the Northrop Grumman Cygnus Mk. IV Automated Logistics Vehicle, was much larger than the ISS supply modules of its ancestry. With its cluster of fresh fuel tanks and nuclear-electric plasma engine, it made for a dazzling sight tumbling through space. To the uninitiated, it wouldn’t have seemed all that bad until one realized the vessel grossed almost a hundred metric tons.
Keeping formation with it, as Jack had suggested, was when things got sporty.
“This sucks,” Jack grunted, blinking hard to clear his vision against the sideways g-forces. Roy had started them flying a one-kilometer circle around their target, matching yaw rates while slowly closing the distance. The real trick was keeping them pointed nose-to-nose with Cygnus, an effect not unlike being at the end of a carnival Tilt-A-Whirl. After so many weeks of low gravity in a normal direction, it was that much more debilitating.
“On the bright side, my sinuses are clear now,” Roy said with a loud nasal honk.
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