“If I’m right, there’s a secondary harmonic.”
“What interval?”
“About one-third of the orbital period.”
Her fingers moved.
“Thirty-one minutes.”
“Yes.”
She searched.
The garage became quiet except for the radio and the faint ticking of Raymond’s cooling engine.
Eleanor stopped scrolling.
Her expression changed.
“Thirty-one-minute secondary component.”
Isaac nodded.
“You have it?”
“Repeated over the last sixteen days.”
“What amplitude?”
She read the value.
Isaac’s face hardened.
“That’s worse than I modeled.”
Eleanor looked at him.
“You predicted the failure six years ago without orbital data.”
“I predicted the mechanism.”
“That’s not the same thing.”
“No.”
Isaac placed the pencil down.
“It’s enough to know you have a problem.”
“Can you fix it?”
He looked at the folder.
Then at Raymond’s truck.
Then toward Dale’s shop across the road.
“I can tell you what’s happening.”
“That wasn’t the question.”
Isaac met her eyes.
It had been years since anyone had spoken to him as though his answer might decide something larger than whether an old truck made it through inspection.
He did not know whether he liked the feeling.
“Come back in two hours.”
Eleanor blinked.
“What?”
“I have work.”
“Mr. Merritt, OBSIDIAN-7—”
“Will still be failing in two hours.”
“You understand the urgency.”
“I understand exactly enough not to start guessing because you arrived in three black trucks.”
Her mouth tightened.
Isaac continued.
“Raymond Ellis is seventy-three.”
“He needs this truck.”
“I told him I’d have it running.”
Eleanor stared at him for several seconds.
Then nodded.
“Two hours.”
Isaac went back under the Ford.
Across the fence, Dale Hutchins watched a NASA director climb into a black SUV and remain parked in Isaac Merritt’s lot.
For once, he did not make a joke.
Six years earlier, Isaac Merritt had worn pressed shirts.
He had an office badge.
He had twelve patents.
He had a title long enough to require two lines on his email signature.
Senior Propulsion Systems Engineer, Advanced Orbital Platforms Division.
He had been thirty-eight then.
Nexora Aerospace occupied an entire campus north of Houston.
Glass.
Steel.
Security gates.
Wind tunnels.
Environmental test chambers.
Clean rooms.
Executives who used phrases like mission confidence and schedule integrity while watching calendars more carefully than hardware.
Isaac had loved the work.
That was the part he almost never admitted after leaving.
He had not merely been good at aerospace engineering.
He had believed in it.
His father, Raymond Merritt, had repaired engines in Harlow but kept an old photograph of the Apollo 11 launch above the shop desk.
When Isaac was eight, his father took him outside during a meteor shower and told him every machine ever sent into the sky had begun as somebody’s drawing.
Isaac never forgot that.
He studied mechanical engineering at Texas A&M.
Then propulsion systems.
Then computational dynamics.
He spent the first years of his career working test programs where mistakes destroyed hardware instead of people.
He learned to love failure when it happened inside a controlled chamber.
Failure showed the truth.
By thirty-five, he had been recruited by Nexora.
By thirty-eight, he was one of the engineers trusted with the Prometheus Drive Assembly.
It was not an engine in the cinematic sense.
It was a compact propulsion and attitude-management architecture designed for long-duration orbital platforms.
Its selling point was reliability.
Redundancy.
Low-maintenance service life.
Its weakness, Isaac believed, was hidden inside a small secondary pressure regulation valve no investor would ever see.
He found the problem during what was supposed to be a routine tolerance review.
The valve passed laboratory qualification.
It passed vibration testing.
It passed thermal testing.
Separately.
Isaac kept thinking about the word separately.
Space did not test systems separately.
Orbit did not wait for vibration to end before changing temperature.
A satellite did not experience one discipline at a time simply because different departments owned different spreadsheets.
Isaac built a combined model.
Then rebuilt it.