…But the Saturn V overwhelmed personal considerations like that. The Saturn was so damned big.

Fahy had grown up with Shuttle. But the Saturn V was just about twice as tall as the Shuttle stack. And those balky F-1s, which had given the guys at Marshall so much trouble, could each develop the power of four Shuttle main engines.

The Saturn, assembled, was like some dinosaur, returned to stalk the Earth. She began to feel intimidated by the booster, as if it would be impossible for her, a mere human, to control it.

Testing and cheek-out went on. There were hundreds of tests of the completed booster’s electrical networks, fire detection, telemetry, tracking, gyroscopes, computers, pumps, transducers, valves, cables, plugs, hydraulics. That took four months alone. Then there was a further set of integrated tests of the booster with its payload and the ground support equipment. There were tests of contingency procedures in case of a malfunction at launch — for instance, if an umbilical swing arm failed to disconnect. There were integration tests to check the hundreds of wire and cable pathways connecting the stages and payload, tests of each of the hundreds of pins in the umbilicals’ electrical interfaces with the vehicle.

Slowly, painfully, Fahy could see progress being made; verification seals and sign-offs started to accumulate, immersing the vehicle in a kind of invisible scaffolding of paperwork.

And, eventually, the booster was rolled out to Launch Complex 39-A.

At the pad, the technicians began more layers of tests: a plugs-in test of all the system’s components, a flight readiness test, a full simulated launch and mission, and a Countdown Demonstration Test, a crucial checkout for the bird’s preparation for launch. In the days of Apollo, CDTs would take maybe four days — sixty hours of testing, and thirty-six hours of planned holds. Fahy hoped they’d get away with not much more than that — say, six or seven days.

The test took seventeen days.

None of the equipment — either the stuff modified from Shuttle operations, or old Saturn gear dug out of storage and refurbished — seemed to work the way it was supposed to. The regulators which controlled the flow of propellants into the Saturn’s stages kept throwing up problems; they simply weren’t designed for such heavy flows. The Saturn V’s own Instrument Unit — the brains of the bird, stuffed full of antique 1960s electronics which nobody dared tear out and replace — couldn’t keep the electronics boxes as cool as they needed to be. Cable connections on the S-II shorted out, in the humidity and moisture around the pad; when they were checked they were proved to be corroded, damage missed by the refurbishment teams.

Everything took much longer than planned.

Even when propellant loading began, the process took hours, as more than a hundred truck-loads of kerosene, lox and liquid hydrogen were pumped into the Saturn’s three stages. And every time the countdown test hit a problem and had to be stopped, the propellants guys had to stay in the Firing Room and detank, a process even more tedious than tanking.

The various teams became exhausted as the test dragged on. Eventually the managers ordered a two-day break.

But still the test limped on, eroding through its checklist. The team got through to the twenty-six-minute mark, the completion of the test of power transfer. Then they began the process of prechilling the thrust chambers in the second and third stages.

Then, amazingly, they reached the start of the automatic count sequence, at minus three minutes and seven seconds. Fahy watched as the final automatic procedures cycled through, controlled by 1960s software re-engineered to run on computer hardware vintage 2007…

The clock stopped, as planned, at minus fourteen seconds.

Now, forty years late, AS-514 was at last a fuelled, checked-out, fully operational vehicle, and the team had done everything it would do on the launch day except light the igniters.

There was a burst of ragged applause.

Good God almighty, she thought. We’re really going to do this.

On the last day, Fahy walked among the crowds at the KSC visitors center. She heard grandparents pointing out the needle-slim Saturn on its pad. They tried to tell their grandchildren about how they’d watched the launch of Apollo 11 — or 12, or 13, or 14 — when they were little kids themselves.

The kids looked on, bemused, asking questions — they’re really going to throw all of that away? how much junk did they leave on the Moon? is the Moon really as messed up as they say?

Fahy rode up the gantry elevator to the payload check-out room at the top of the stack. The elevator was an open metal cage, and it rose with bumpy rattles and clangs; she climbed past steel beams, cables, work platforms.

When the elevator stopped, she stepped through the gate onto a railed catwalk. It spanned the gap between the elevator and the curving flank of the booster, with its open access panels. She looked down the complex, curved flank of the Saturn to the huge steel platforms far below, the flaring skirts over the big F-1 engines, diminished by perspective.

An ocean breeze picked up, and there was a ponderous creak of metal. The catwalk seemed to tilt, and she had to grab a handrail for support. This huge mountain of steel was swaying.

When she looked away from the booster, she had a panoramic view of the Atlantic coast. It was early evening, and the coastal towns strung out along the edge of the land sparkled like jewels. But the land itself looked flat, muddy, primeval, barely poking above the water, and the water of the ocean and marshes and canals shone like beaten metal. It was like, she imagined, the place where the first amphibian had crawled painfully, the air like fire in its new lungs, its belly and tail working at the sand, striving to get back to the water…

In a few years, she reflected — when the pads and gantries were torn down and hauled away at last — maybe the sea, the ancient swamp, would swallow up this place once more.

Marcus White got to the Launch Control Center of KSC in the predawn, a couple of hours before the launch.

The Firing Room was a big hall, a third the size of a football field, with eight rows of consoles. White took his place in a glassed-in viewing area set off at an angle at the back of the Firing Room, and looked out through the big picture windows over the pads.

AS-514 was bathed in a cone of light, set up by big searchlight beams that met at the tip of the stack, and the lights of its gantry gleamed like a ship’s lamps.

The daylight started to come up. From the Firing Room, White was looking east, into the gathering dawn; soon Launch Complex 39-A was silhouetted against the sky. The breeze was blowing debris around the pad, and the wind meter at the top of the tower was spinning around. But the forecast said the windspeed would be within weather rules at launch time.

The paintwork of the refurbished Saturn gleamed, and the booster, slim beside the blocky orange tower, looked oddly feminine, delicate. White felt a lump, unwelcome and painful, gathering in his throat. To hell with Titan. It was all worth it, he thought, just to see that old lady fixed up and with the lichen and moss and streaked paint scraped off, raised up to where she belonged.

He followed the slow evolution of the count, under the control of the KSC Firing Room staff. Events were accelerating, as the tanks in the various stages went through their cycles of precool, fill and replenish. It seemed inconceivable that AS-514 was going to lift on time. But there were no holds today. He sensed the buildup of the indefinable momentum that gathered about a mission, as it prepared for a crucial new phase.