“You should know better than to ask me that, Malenfant.”

“Yeah. Sorry.”

She was still under forty, but she wasn’t aging well, he thought. Her hair remained thick and jet black, but her oval face had shed its prettiness: grown angular, the bones showing, her eyes dark and sunken with suspicion. Her voice, from the softscreen’s tiny speakers, was an insect whisper. “You are enjoying the conference?”

“Not much.” He shared with her his gripe over too many philosophers.

“But there are worse fools. Here is some more philosophy for you: ‘This is the way I think the world will end — with general giggling by all the witty heads, who think it is a joke.’ Kierkegaard.”

“He got it right.” Whoever he was.

“And philosophy can sometimes guide us, Malenfant.”

“For instance—”

“For instance, the notion of equilibrium…”

It was like resuming a conversation they had pursued, on and off, for nine years; a slow teasing-out of the koan.

After their notoriety following the announcement of the aliens in the belt, Nemoto had recoiled completely. She’d refused all offers of public appearances, had quit her job, had turned down offers of research positions from a dozen of the world’s most prestigious universities and corporations, and had effectively disappeared. All this while Malenfant had slogged around the public circuit with diminishing enthusiasm, enduring the brickbats and bouquets that came from his sliver of fame. She had been an Armstrong, he sometimes thought wryly, to his own Aldrin.

But she was continuing her researches — though what her purpose was, and where her money was coming from, he couldn’t have said.

She didn’t like the Gaijin, though. That much was obvious.

“We imagined only two possible equilibrium states: no aliens, or aliens everywhere,” she said softly. “We have diagnosed this moment, the moment of first contact, as a transition between equilibriums, brief and therefore unlikely for us to be living through. But what if that’s wrong? What if this is the true state of equilibrium?”

Malenfant frowned. “I don’t get it. Contact changes everything. How can a change be described as an equilibrium?”

“If it happens more than once. Over and over and over. In that case it’s no coincidence that I happen to be alive, here and now, to witness this. It’s no coincidence that we happen to have a technical culture capable of detecting the signals, even initiating contact, of a sort, just at this moment. Because this isn’t unique. ”

“You’re saying this happened before? That others have been here? Then where did they go?”

“I can’t think of any answers that don’t scare me, Malenfant.”

He studied her. Her eyes were almost invisible, her face an expressionless mask. The background was dark, anonymous, no doubt scrambled beyond the reach of image-enhancement routines.

He considered what to say. You’re spending too much time alone. You need to get out more. But he was scarcely a friend to this strange, obsessive woman. “You’ve spent a lot of time thinking about this, haven’t you?”

She seemed offended. “This is the destiny of the species.”

He sighed. “What is it you called me about, Nemoto?”

“To warn you,” she said. “It isn’t quite true that we are waiting on Frank Paulis and his space probe for new data. There are two items of interest. First, a fresh interpretation. I’ve been able to deduce patterns from the infrared signature of the Gaijin’s activity in the belt. I believe I have determined their pattern of propagation.”

Her face disappeared, to be replaced by the virtual display of the type she’d first shown him in the silence of the Moon. It was a ring of glistening crimson droplets, slowly orbiting: the asteroid belt, complete with dark Kirkwood gaps. And there was the gap with the one-to-three resonance with Jupiter, with its string of rubies, enigmatic, brilliant.

“Watch, Malenfant…”

Malenfant bent close to the screen and studied the little beads of light. The images cycled with small vector arrows, which showed velocity and acceleration. The rubies weren’t in simple orbits about the Sun, he saw; they seemed to be spreading around the belt, some of them actually moving retrograde, against the motion of the rest of the belt.

The motion was intriguing.

“Imagine the arrows projected backwards,” Nemoto said.

“Ah,” Malenfant said. “Yes. They might converge.”

Nemoto cut in a routine to extrapolate back from the Gaijin sites’ velocity vectors. “This is rough and ready,” she admitted. “I had to make a lot of assumptions about how the objects’ trajectories had deviated from simple orbits through the Sun’s gravitational field. But it did not take long before I found an answer.”

The projected paths arced out of the asteroid belt — out, away from the Sun, into the deeper darkness, before converging.

Malenfant tapped the screen. “You found it. The prime radiant. Where these probes, or factories, or whatever the hell they are, are emanating from.”

“It is one point four times ten to power fourteen meters from the Sun,” Nemoto said. “That is—”

“About a thousand astronomical units out.” A thousand times as far as Earth from the Sun. “Somewhere in the direction of Virgo… But why there?”

“I do not know. I need more data, more work.”

“And your second item?”

She eyed him. “You are meeting Maura Della. Ask her about Rigil Kent.”

Rigil Kent. Also known as Alpha Centauri, nearest star system to the Sun, four light-years away.

“Nemoto—”

But the softscreen had already filled up with the everyday froth of the online news channels; Nemoto had receded into darkness.

He was taken to lunch by former congresswoman Della.

After lunch they strolled around the conference hall, glancing at poster presentations and the fringe sessions. Malenfant felt uncomfortable being out in public like this.

“I wouldn’t be too concerned,” Maura said. “Not here; you have to be afraid of the ones who stay at home polishing the telescope sights on their rifles.”

“Not funny, Maura.”

“Perhaps not. Sorry.”

She hadn’t said a significant word during lunch; now he couldn’t contain himself any more. “Rigil Kent,” he said.

She slowed to a halt. Her voice low, she said, “You spoiled my surprise. I should have known you’d find out.”

“What’s going on, Maura?”

For answer she took him to a small, overpriced coffee bar. On a handheld softscreen she showed him images of the great radio telescope at Arecibo, various microwave satellites, activity in the Main Bay at JPL: arcs of consoles, young, excited engineers on roller chairs, information flickering over screens before them.

“Malenfant, we’ve picked up a signal. From Alpha Centauri.”

“What? How — ?”

She pressed a finger to his lips.

As it turned out — though this bit of news had been Maura’s true motive for inviting him here — there was little more to tell. Maura had gotten the news from her contacts in the government. The signal was faint, first picked up by an orbital microwave satellite. But it was nothing like the neatly structured Lincos signals humans had been sending to the asteroid belt. It was heavily compressed, a mush of apparently incoherent noise, with only evanescent hints of structure — much what Earth might have sounded like, from four light-years away.

“Or it may be an efficient signal,” Malenfant said hoarsely. “It can’t be cheap to signal between the stars. You’d take out as much redundancy — repetitive structure — as possible. If you don’t know how to decode it, such a signal must look like noise…” Either way the implication was clear. This wasn’t a signal meant for humans.

But whoever was there, at Alpha Centauri, had only just started to broadcast — or rather, only four years in the past, given the time it took for signals to crawl to Earth.