A factory on A Level made lightweight buckets of a special superconducting polymer. These were loaded with iron and other heavy wastes. Each metal-filled dollop became a bullet. Conveyors fed these with unrelenting precision into the flinger barrel, where the surging voltages clasped each pellet and flung it to enormous speeds— ten thousand kilometers per second, nearly three percent of the speed of light. Launcher 6 was a cosmic machine gun, firing slugs that would reach the nearest stars in a few centuries.

We could have built starships, if we’d only had the nerve, Carl thought. Maybe someday.

Such was the mass of Halley that even these enormous speeds were barely sufficient for the task of piloting. Carl tuned in to an engineering frequency and herd a staccato braaap braaap braaap as each pellet picked up its miniboosts in the flinger column. Launcher 6 was the first of fifty-two that would soon ring Halley, stuttering forth their kilogram pellets for five years. Aphelion, when the comet head paused like a ballet dancer at the peak of his leap, was the most efficient time to divert Halley. Fully ten millionths of the comet’s entire mass had to be ejected. That demanded dozens of mechs supervising the mining and smelting of iron, minirobots to toil beside the endless conveyor belts, subroutines and expert programs to catch every snag, each hitch in the unending stuttering fever of the Nudge.

“Goddamn,” Carl said. “It works.” He felt a rush of relief and realized he had been clenching his hands.

The cheering went on. Even this demonstration, which would run for a mere few hours, was slowing Halley’s primordial spin, minutely altering its long gliding ellipse.

—Runnin’ smooth, too,—Jeffers said, grinning happily.

—Come on down to Launcher Five. I’ve got a nice li’1 pivot rigged there, keeps the flinger tube from comin’ unglued. We figured—

Jeffers stopped abruptly as a geyser of steam boiled from an ice tower nearby. Vidor’s intricate cross-hatching of blue and ivory exploded in a shower of fog and glinting, tumbling remnants.

—Goddamn!—

—What? What’s happenin’?—

“Laser!” Carl flattened himself against the grimy ground. “Get down everybody!”

—What the hell— who’d go and—

“Arcists!” Carl realized “They must’ve heard the successful test over comm.”

Jeffers shouted,—But why? I thought Quiverian agreed.—

“Damned if I know.”

All across the field, people were ducking for cover. An ice tower farther away dissolved silently into mist. This time Carl saw the flash of light as the beam struck.

“They’re firing from that hill— over there. South twenty-five degrees of west.”

Jeffers squinted at a distant speck atop a heap of leftover slag from one of the mining operations.

—They moved one of those big industrials. Tryin’ to hit Six, but those things, they don’t aim all that good.—

The comm rang with outrage.

A bolt gouged into ice near a crouching form and Carl heard a startled tied cry of pain.

“Takeda! Get that woman sealed and to first aid!”

Carl crouched behind a hummock and watched fierce laser bolts send fountains spurting skyward. “Bastards!”

—We gotta do somethin’.—

“I could have Virginia send some mechs around behind, outflank them…”

—Yeah, right,—Jeffers said.

“No, wait…” He checked Virginia’s channel. A hiss. It was cut off. Of course. Only an idiot would attack without cutting off the defender’s source of support.

Another wail of pain over the comm.

Carl nudged Jeffers’s shoulder. “Launcher Six-can you pivot it?”

—What?—

“Tip Six down? Aim it at the horizon?”

Jeffers looked surprised.—The safeties aren’t in. I dunno… that’s a pretty low angle.—

“Try it!”

As Jeffers crawled into the launcher trench, the ice-tower fulcrum for Launcher 5 exploded behind them, sending cables and cowlings into a slow, fluid fall to the surface. Lost components, lost construction time, hurt crew— people who were his responsibility. Carl glowered at the distant dots working around the laser cannon, a murderous anger building in him.

He tuned out the comm channels, where voices swelled and swamped one another. People called for lovers and friends, sputtering in impotent rage. Mechs asked innocently for orders. Then Virginia’s voice intruded on his private line.—What’s going on? Somebody jammed my channels. Who…?

“Get some weapons up here!”

—But, but, what’ll we use?—

“Those small lasers in Three B— that’s all we’ve got that we can move right away.”

—But won’t they just pick off anybody who comes close enough to use small lasers?—

Carl swore. She was right.

—I can send some big mechs from the north pole.—

“We’ll be toast by then!”

He whistled a search-and-contact command for Joao Quiverian and had a channel in seconds. “Quiverian! This is Osborn. You—”

The man’s voice was strained. —Those are not acting under my orders. Arcists they are, yes, but I cannot control them.—

“You expect us to believe that?”

—You must. It is the truth.—

Carl gritted his teeth. So the enemy was faceless. Anonymous. The people using those big lasers weren’t going to allow anyone else to take over the Nudge options, to try another orbit. With them it was all or nothing… and they would take all.

On the general comm, more screams as an invisible laser bolt struck a hillock and dissolved a deep pit into it. Carl saw a body roll away… someone hiding there.

He used command override on channel A. “Get those people off that slag mound by Launcher Two! All of you, take shelter down in the feeder tunnels.” A babble in reply. “And use ident codes if you want to be heard!”

He spoke a quick command in mech-talk and the noise cut off as the channel controller went over to formal mode. Now suit radios would not even work until the system passed on your code-ordering. For a moment there was only an eerie hiss. Then,—Jones, BQ code to Osaka and Osborn. Leading party of five down to shaft now.—

—Lomax, DF code, to command. Got a good view from a safe height. Everyone P-code your sitings to me. I’ll relay situation to Osborn.—

Carl nodded. A few good spacers who remembered their training were worth battalions.

—Jeffers, GH code to Osborn Got it I think.—

“Osborn, GH code. Got what?”

—Jeffers, GH. I’m tipping the launcher down. Got to turn it toward the south. You line it up, okay?—

Carl realized that the steady hammering of Launcher 6 had stopped some time ago. Now, as he watched, the assembly turned laboriously toward the distant low hills, its snout tipping downward. Carl got to his feet and swiftly moved behind the slowly swiveling launcher. The only way he could think to aim the thing was to eyeball it directly, sighting along the barrel.

Great. Real high-tech.

And the Arcists were undoubtedly watching them closely. Their objective must be this site. They had destroyed the easier targets while they were getting the range right. Launcher 6 was much harder to hit, buried in its trench. But now that it was slowly emerging…

He squatted down onto a patch of orange stain and closed one eye automatically, lining up the launcher barrel with the specks on the distant hill.

—Lomax, DF to Osborn. Got a tactical sketch of known enemy positions. Prepare to receive. They’re bunched up pretty close.—

Carl threw the picture over half his faceplate. Benchley’s rough drawing showed a main group and two wings— probably outlying spotters.

Not many of them. I count five. But they’ve got the best ground.

The Arcists were settled into a notch, taking advantage of the shelter. As he watched a bright blue flash winked— and he ducked automatically. Which was ridiculous; if he was in the full focus of the laser it would have blinded him instantly. Instead, they had aimed high. Only the fringing fields had struck him.