Charles Sheffield - Starfire

“ Made to happen?” One of the data analysts spoke — Raymond, thought Maddy. No, Raoul. “ You mean somebody out there decided to make a supernova, just so they could wipe out humans? You’re saying aliens exploded Alpha Centauri?”

Wilmer frowned. “You have expanded on Star’s hypothesis. She did not say that, and I am saying only that we are involved in an event inconsistent with the standard theories of stellar evolution.”

“But if it’s not that, and aliens—”

John interrupted. “We’ll worry about alternative theories later. You say that you’ve done a calculation and have an answer?”

“Star has.” Wilmer nodded to his young protégé, who was bouncing excitedly on the edge of her seat. “Go on, girl. Tell ’em, before you burst.”

“Yer have ter make some more assumptions before yer can get an answer.” Star hopped up and went to the board. “Like, symmetry about the midpoint, and a parametric form for the strong-force modification that we assume holds the particle bundles together. But given that, and assuming that everything else goes linearly, the best guesstimate I can make says we get hit with everything emerging from a solid angle of one two-hundredth of a steradian of Alpha C. That’s instead of everything coming from mebbe one three-thousandth, if we had a spreading cone.”

“Translation?” said Lauren Stansfield. “I can’t think in those units.”

“The blip storm that arrives tomorrow will be about fifteen times as severe as we thought,” Wilmer said. “It’s not a blip anymore.”

“A factor of fifteen. That’s bad, but not totally disastrous.” Lauren Stansfield was examining a sheet of notes. “Sky City will survive. From what Will says, the shield won’t be totally destroyed. Earth will be worse off.”

“Maybe.” John had been watching Wilmer Oldfield’s face. “That’s not the whole story. Is it?”

“Looks like not. The convergence we’re talking about applies to the whole particle flux, not just the small peak. Assuming Star’s numbers hold up — we’ll have a better test of that when the latest Sniffer hits the wave front — then everything scales by the same factor. The maximum particle density will be up by a factor of fifteen. Same factor for the energy that hits Earth.”

“Fifteen.” John was already moving to the message console. “I assume the direction the particles comes from doesn’t change.”

Wilmer shrugged. “Tiny bit. Not enough to notice — the beam convergence factor is less than one in a thousand. It’s the energy delivered that we have to worry about. Without convergence, we predicted a maximum energy per square meter hitting the top of Earth’s atmosphere at about three thousand watts per square meter. That compares with about fifteen hundred watts per square meter coming from the Sun as radiation. Now we’re saying the energy from the particle storm will peak at more like forty-five thousand watts per square meter.”

“Thirty times as much as the Sun?” John was opening simultaneous circuits to Bruno Colombo, Nick Lopez, and Urbain Tosca. Let Bruno be as mad as he liked over the breach of regular protocol.

“Thirty times as much energy as the Sun,” Wilmer corrected. “But it’ll be coming in a very different form. Instead of light you have charged particle bundles. We’ll have strong forward scattering, tons of ionization, and God knows what secondary effects.”

“One worry at a time.” The lines were opening, and John could hear startled voices at the other end. Direct messages from the Sky City engineering information center were without precedent. “I ought to have known that something like this was going to happen — the work on the shield and the field generators has been going too smoothly.”

Maddy, ignored at the back of the room, wondered if she had misunderstood everything. She had followed few of the exchanges, except Raoul’s suggestion that the whole Alpha Centauri supernova had been intentional and created by aliens. But regardless of explanations, weren’t they saying that in less than two days Earth would be hit by a particle storm thirty times as bad as anyone had expected? And if that was the case, why was everyone so calm?

She knew the answer. No wailing, no moaning about the imminent end of the world — because everyone with her was either an engineer or a physicist.

Maddy looked around, inspecting the others one by one. You didn’t have to go all the way to Alpha Centauri to find aliens. There was a roomful of them right here.

Alpha Centauri lies at sixty degrees south on the celestial sphere. The preliminary particle storm — call it a blip if you like, but no longer dismiss it as insignificant — would hit Earth from that direction, with the zero hour of peak maximum occurring at three-fifteen local time. Every prediction from Celine Tanaka’s science advisor, Benedict Mertok, said that Washington, at thirty-nine degrees north, should be affected only in minor ways.

And yet …

Mertok was confident and knowledgeable and polished, the very model of a modern senior advisor, but the person whose opinion Celine really trusted was Wilmer Oldfield. She placed a call to Wilmer on Sky City early in the morning. She had to radiate public optimism, but she needed to know the worst.

“Know for sure? Can’t tell you that. Might as well be betting on a horse race.” Wilmer was sitting at a Sky City communications unit and steadily consuming the huge breakfast of a man without a care in the world. At Celine’s question he touched his hand to the bald spot on top of his head. “Star and me have a theory, you’re right about that, but it’s not a tested theory. We need new Sniffer data. We’ll be able to give you a better answer in a few days.”

“Wilmer, a few days is no good.” Celine had drunk lots of coffee and barely nibbled at dry toast. How could anyone eat the way he did so early in the morning?

“We’ve got a psychic calling all the media, telling people that the world is going to end at three-fifteen this afternoon. The Fist of God will strike, and Earth will split open like a melon dropped from a tenth-floor window.”

“He’s an idiot. You can quote me on that.”

“It’s a woman. So this won’t be the end of the world. But what will happen? I have all emergency services on standby alert. I have a national broadcast this afternoon. I have fourteen planeloads of people asking permission, right now, to take off and fly south.”

“Fly south ? What for?”

“God knows. I guess for the fun of it. They’re thrill seekers who see themselves as daredevils, on the way to Tierra del Fuego for a big whoop-de-doo storm party. I’m in a tricky position. On one hand, I’m supposed to make sure there’s no panic, and to do that I have to minimize talk of danger. On the other hand, I don’t want even lunatics to head south if they’re likely to kill themselves. I need to know what to tell them, and everybody else. That’s why I called you. I wasn’t just being sociable.”

“I can see that.” His face was serious, the heavy brow furrowed in thought. “Celine, me and Star can’t tell you what’s going to happen today, and we shouldn’t be telling you what to do. But let me say this for starters: Every single thing we’ve ever assumed about the Alpha Centauri supernova turned out later to be wrong.”

He paused, for so long that Celine in her caffeine high wriggled in impatience. She wanted instant answers. Except that thirty years of experience had taught her that Wilmer wouldn’t be hurried.

“We talk as though we know a lot about supernovas,” he continued at last. “We don’t. They are extremely rare events. You have only one or two a century in a typical galaxy, and most of them take place so far away that they give us little information. Did you know that there hasn’t been a naked-eye supernova since the invention of the telescope? That’s four and a half centuries. When scientists tell you we understand supernovas, they mean something very specific and very limited. What we should say is that we have been able, through computer models, to show how certain kinds of stars and stellar systems can produce the enormous energy release that characterizes a supernova. That doesn’t mean no other type of star can possibly explode, or that some other supernova-creating mechanism can’t exist. The limits we assign to Nature sometimes define our own lack of imagination.