INTERLUDE:

APRIL 1968

Christmas of 1967 had been as rushed as everything else that year.

Then, for Seth Springer, the spring of 1968 was a blur of work. Once, for “diplomatic” purposes, Seth even had to haul ass to Kazakhstan, deep in the heart of the Soviet empire, to witness the launch of one of the unmanned probes they were calling Monitors: basically American Mariner probes of the kind that had been sent to Mars and Venus, launched on the Soviets’ sturdy new Proton rocket boosters. There would be one Monitor on hand at each of the six interceptions, the six nuclear detonations that were meant to push Icarus away from its date with the Earth.

But Seth suspected that—assuming he lived through this adventure—what he was going to remember most of all of this time would be the hours, days, weeks he spent in the mission simulator at Houston.

The simulator itself was the size and shape of a conical Command Module cabin, embedded in a rats’ nest of cabling, wiring, and huge stuck-on boxes that generated visual emulations of mission events. The controlling computer, in air-conditioned security in its own compartment behind a glass wall, looked smugly down on the astronauts, the mere humans who had to crawl into the middle of the thing. Which was galling when you remembered that humans were only being drafted in for this fallback mission in the first place because nobody really trusted computers alone to do the job. Seth wondered if it was rational to have a relationship with a machine, even if it was one of irritation and resentment.

Seth and Mo took it in turns to ride the sim, Mo as primary pilot taking the lion’s share of time. But whichever pilot wasn’t in the can would be in Mission Control, assisting the other. Here, working with the flight directors, they worked up plans and checklists for all the crucial moments of the sixth flight of Apollo-Icarus, should it be needed, down to every switch that had to be thrown, every command that had to be punched into the guidance computer. And then they started working on contin­gencies: if system A fails, do this; if system B fails, do that. They did this over and over, until it became instinct.

Seth would always admit that Mo was the better pilot, and picked up stuff quicker than he did. Seth, in fact, counted it a victory when in a given day he screwed up fewer times than the overloaded computer “bombed out,” as the sim controllers put it. But given enough time, their performances would be indistinguishable.

The trouble was, there never was enough time.

And suddenly it was April 1968, and the programme went live.

On Sunday the seventh, bang on time, the first Apollo-Icarus Saturn V, with its big nuke aboard, was successfully launched. For once Seth and Mo were together to watch the launch, which went flawlessly. But even as the Saturn disappeared into the sky from Pad A, a second Saturn was already sitting on Pad B being prepped for the second launch on April 22, and Pad A itself was being torn down to be made ready for the launch of Apollo-Icarus 4 on May 17.

It was a consequence of the compressed schedule and the fast approach of the asteroid that by the time the first flight reached Icarus itself, at the maximum feasible distance of twenty million miles, three more flights would already have been fired off. Still, to see that first bird go on time was a major milestone, a huge motivator for everybody.

It was as the second launch approached that everything changed.

On April 21, a week after Easter Sunday, Seth showed up at the Cape to witness the launch due the following day. Mo, on his way in from Huntsville, was flying independently, in his own T-38.

But Mo was overdue.

In the late afternoon George Lee Sheridan called Seth into a private lounge in back of the launch control bunker, and handed him a glass of bourbon.

“We don’t know what happened yet,” Sheridan said. “Ground observers say the damn bird just went out of control—a roll—it took a dive straight at the ground. Still supersonic when it hit, they estimate. Damn those T-38s. I know you guys love your toys.”

Seth stared at the bourbon, trying to take this in. “We ought to measure the size of the crater he made.”

“Hmm?”

“We were taken to a lab in Texas where they were simulating lunar craters by firing cannon into the ground. Measuring basin diameter as a function of incoming kinetic energy.” He forced a smile. “Mo would want to end up as a data point on one of those graphs. It would make him laugh.”

“I’ll drink to that,” Sheridan said. He eyed Seth. “This changes everything. The truth, the existence of Apollo-Icarus 6—Mo’s true mission, and yours—broke as soon as the crash did. Amazing we kept it quiet so long, I guess. First things first. There’ll be a funeral at Arlington. I have to ask you to attend that. We’ll fly you in by Gulfstream. Service uniforms and horsedrawn carriages and rifle fire, and the missing man formation in the sky. Families—well, whoever we can find for Mo. You’ll have to make some kind of speech, alongside RFK, maybe even the President.”

“I understand.”

“Then we’ll move you into the crew building on Merriott Island. Pat and the boys too. We won’t let the press or anybody else near you—anything you want.”

“I appreciate that.”

Sheridan drank again. “This is a tragedy, but it doesn’t change the urgency of the mission. Even if you never need to fly, you’re a symbol of the effort we’re making. It’s not just about Icarus, you know. Look at the offensive the Viet Cong launched in January . . .” Atrocities on both sides, as undermanned American positions had been overrun. Sheridan shook his head. “Some things they didn’t ought to show on TV. Then Martin Luther King gets shot, and the whole country’s like a damn brush fire. And in the middle of all that, still invisible in the sky, Icarus is on its way.

“You know, I went to a preview of a new space movie, some damn science fiction thing. Opens with ape men beating each others’ brains out with clubs made of bone. Is that all we are? I prefer to think we are better than that. In my own lifetime, in the ’30s I worked on the New Deal, a war on poverty, in the ’40s I was involved in a total war against fascism, and in the ’50s I was on the technological front line of a nuclear confrontation. And now, this.

“I believe we can work together, that an advanced technological nation like the United States can be shaped for a worthy goal—like beating Hitler, like putting a man on the Moon, yes, like swatting Icarus aside. And after we’re all long gone, the work we do now will be an inspiration for all mankind, in the future. Your kids and grandkids, Seth. They’ll know that this is what our generation did.” He reached over and grabbed Seth’s shoulder. “Listen, son, if we do need you, I’ve as much confidence in you as I would have had in Mo.”

Seth believed him. But all he could think of now was what he was going to have to say at Arlington. And how he was going to break all this to the boys.

Anyhow, the chances were still that he wasn’t going to have to fly.

He’d forgotten his bourbon. He drank it down in a gulp.