“One more thing. This is coming straight from me. I … I might as well tell you something I’ve realized for a while, but haven’t told you.…”
“What is it, Scott?”
“Kimberly…” He sounded choked up. “I … I…”
Kimberly felt her face grow warm and started to speak, but she sensed a slight, sudden vibration in the ISS. She barely floated toward the JPM wall, drifting incredibly slowly, but moving nonetheless.
“Kimberly! What’s going on? You’re moving out of video range.”
That’s strange, Kimberly thought. She couldn’t feel any increase in air flow through the module, but if she was being carried along by moving air, then of course she wouldn’t feel any current. It would be like not being able to feel the presence of wind when you’re in a hot air balloon. She’d be carried along with the flow …
She heard a low thrum. She realized she wasn’t floating inside the module, but rather the JPM was moving, slowly rotating around.
In fact, it wasn’t just the JPM. The entire ISS was moving.
She twisted in the air and swam over to the laptop. Quickly she pulled up the graphical interface.
Her pulse thudding in her ears, Kimberly saw that the state for the helium pressure valve had just been switched from OFF to ON. The hypergolic propellants were pressurized and fueling the thrusters.
The ISS was rotating around, and in ten minutes when its engines were facing in the direction of motion, it would soon start its fall to Earth.
MAUI SPACE SURVEILLANCE SITE, MOUNT HALEAKALA, HAWAII
Second Lieutenant Chip Johnson struggled to stay awake in the small vault while sitting watch at the classified communications console. Three cans of Bang energy drink lay crumpled in the trash can at his feet, almost a thousand milligrams of caffeine. It was enough jolt to revive the dead, but his head kept lolling forward, a casualty of surfing Maui’s north shore earlier in the day.
The twenty-three-year-old Auburn engineer had been on active duty for only six months and considered himself lucky to have been assigned to the Air Force Research Laboratory’s Maui site, based in the small town of Kihei near AFRL’s Maui supercomputer.
But tonight, instead of being down at sea level, as the junior officer in the small military detachment overseeing the contractor staff that ran the seventy-five-ton Advanced Electro-Optical System telescope’s massive twelve-foot mirror, he’d been assigned the graveyard shift at the observatory atop Haleakala’s 10,033-foot peak.
Viewing operations didn’t normally demand the presence of military personnel; the private contractor personnel operating the Air Force’s space surveillance site handled the telescope and its equipment with professional competence. But with classified activities sucking up all the AEOS’s telescope time, the reason for Lieutenant Johnson’s presence was to ensure a continuous Title 10 chain-of-custody for the viewing data gathered by the state-of-the-art surveillance system.
When he’d first arrived at Maui six months earlier, with a newly minted bachelor’s degree in mechanical engineering, Johnson had thought he’d be performing cutting-edge research or solving some high-tech problem, such as working on the lasers or the deformable telescope mirror that took the twinkle out of the stars and gave the system as clear a view of the skies as a ’scope in orbital space. But he quickly discovered that the long-term, experienced contractor people did all the fun stuff like conducting research, and his role was to serve as oversight to whatever activities they were engaged in.
But for the past two days the facility had been tasked with a highly classified Title 10 Operations of War, and the Maui site needed an active duty Air Force officer to pass the telescope’s detailed viewing data through a classified link to Space Command’s JSPOC, the Joint Space Operations Center at Vandenberg Air Force Base.
So now, Second Lieutenant Chip Johnson found himself not merely overseeing routine contractor operations, but being squarely in the middle of certifying tightly classified information from the AEOS’s twelve-foot, adaptive optics system that could reveal details on satellites down to a resolution of less than a foot. He wasn’t sure what the information was being used for, but it seemed strange to be observing the International Space Station every time it passed overhead. Rumors buzzing through the Haleakala facility claimed that the real target was some other satellite that would be observed at a later date, and what they were doing now was just some sort of exercise. In any case, Chip was excited to be finally at the center of the action, and not just sitting on the sidelines monitoring contractors.
So when his nodding head almost slumped onto the communications console, Chip reached for another can of Bang and prepared for another 300-milligram jolt to his nervous system.
“Lieutenant?”
Chip swiveled in his chair while still holding the unopened can. “Yeah?”
Standing at the door to the communications center was Dr. Young, a thin multiracial woman with pale freckles sprinkled across her face.
“Could you take a look at this?” she asked.
“Sure.” Chip turned back to his console. The data links were all working; there was no indication that the AEOS had taken in any information that he needed to pass on to JSPOC.
“What’s going on?” he asked, over his shoulder.
“I’m not sure,” Young replied. Frowning, she stepped up to the console, holding a thin sheet of paper. The comm center, barely big enough for two people, was electronically shielded as a Faraday cage so that its classified communications gear could not be tapped.
“There’s no change in the ISS imagery,” Dr. Young said, sounding slightly uncertain, puzzled. “Since we had time on our hands, we decided to use the overflow crew to calibrate the ISAL against the space station, instead of sitting around, doing nothing. And the ISAL discovered a change in its orbital elements.”
“Excuse me?”
“ISAL: the inverse synthetic aperture laser experiment we’re bringing online to image satellites in geosynchronous orbits.”
“Okay, go ahead.”
“The ISS uses solar panels similar to the communications satellites in geosynchronous orbit,” Dr. Young explained, “so by imaging the space station’s arrays with ISAL, we can compare that imagery to other satellite arrays located at GEO, twenty-two thousand miles higher up. That way we can take into account any difference in what we see at low Earth orbit, where the ISS is, and GEO satellites.”
Chip shrugged. “Sounds like a good use of the crew’s time. But what’s going on with ISAL?”
“Here. Look what happened when we tried to calibrate the laser with a distance measurement.” Dr. Young handed him the paper. Chip saw it was a computer-generated plot of altitude with respect to time. The line was nearly straight, showing a near-constant altitude of the ISS. At first there was a barely perceptible decrease, then suddenly, just a few minutes ago, the station’s altitude precipitously fell. Instead of its normal slow edging lower in altitude due to atmospheric drag, it looked to Chip as though the International Space Station was taking a nosedive, and rapidly falling to Earth.
Chip frowned. “The station’s altitude is decreasing. Is something wrong with the laser?”