“Which is what Paul Fogarty did.”
“Aye. Him, and that Geoffrey Benton.” McAndrew gave me a strange look, which I could not interpret.
“And the place where they heard the signal was south, too,” I said. “But we’re going north.”
“We are indeed.” McAndrew looked smug. “Here’s a question for you, Jeanie. Suppose that you are in trouble, and you can only send out a distress signal now and again.”
“Once every year or two, they said.”
“Right. Now, you’re way out in deep space. Where would you beam the signal?”
“Where people were most likely to hear it. Back toward the Sun.”
“Indeed you would. But if you’re a long way out, and the signal is weak, chances are no one will hear you. Unless there’s some way you can amplify the signal, or you can focus it.”
I’m no McAndrew, but I’m not an idiot. I almost had it. “A signal, sent back toward the Sun — a radio signal. That would be focused just the way that a light beam is focused. But what Paul Fogarty heard wasn’t at the solar focus.”
“No more it was. You’ve had courses in optics, Jeanie, you must have. The Sun acts like a lens, one that takes a beam of light that comes from infinity and converges it to a focus at eighty-two billion kilometers. Now suppose you have a radio signal, but instead of focusing at eighty-two billion kilometers from the Sun it focuses itself at two hundred and eighty billion kilometers. Where would the origin of the radio signal have to be, to make that happen?”
“On the other side of the Sun from where you receive it.” I tried to recall the relevant formula — and failed. I said, “How far out? It’s a standard result in geometrical optics…”
“It certainly is. If a lens converges a parallel beam of light at a distance F from the lens, then light starting at a distance S from the lens will be converged at a distance D beyond it, where the reciprocal of S plus the reciprocal of D equals the reciprocal of F.”
“Don’t gibber at me, McAndrew. I asked you a question. How far out?”
“You’re not listening, Jeanie.” The wretch went on regardless, probably imagining that he was speaking English. “Take F as eighty-two billion, and D as two hundred and eighty billion — that’s where Paul Fogarty caught the distress signal — and you find that S, the distance from Sol where the signal originated, is a hundred and seventeen billion kilometers from Sol. That’s where the distress signal came from, the other side.”
“The other side of what?” As usual, he was turning my head into a muddled mess.
“Of the Sun — the signal was generated on the opposite side of the Sun.”
“You mean Fogarty and Geoffrey Benton have been searching in the wrong place?”
“Of course they have. Completely wrong.” But there it was again, the curious tone in his voice when he said Benton ’s name. And with it, a strange sideways look at me.
Even at a hundred gees acceleration, we were going to be on the way in the Merganser for over a week. Too long to live with seething undercurrents of feeling.
“Mac, what is it with you and Geoffrey Benton? Surely you hardly know the man.”
“I guess I don’t. Not the way you do.”
“And what’s that supposed to mean? I’ve never even met him.”
He stared pop-eyed at me. “How can you say that? He’s the AG Newsman who flew with you back from the Titan prison colony — just the two of you.”
I groaned inside. A fifteen-year-ago fling, coming back to haunt me. “That wasn’t Geoffrey Benton.”
“But he works for AG News.”
“So do ten thousand other people. Mac, what on earth gave you the idea that it was Benton?”
“Paul told me.” McAndrew put a hand to his balding forehead. “It wasn’t Benton? My God. Do you know what I did? Do you know what I called him?”
“I know exactly what you did, and I can imagine what you told poor Benton. More than that, I know what Paul Fogarty did.”
“But why would Paul… he wanted to make the trip to the solar focus as bad as I did.”
“Worse than you did. Mac, don’t be dense. Fogarty wanted to make the trip all right. And he’s making it — without you. You’re older and you out-rank him. You’d have been the leader. Now, he keeps any credit for himself.”
“Paul? Do a thing like that. I don’t believe it.”
But he did. He went silent for hours, cracking his finger joints in the way that I hated and looking sideways out of the ship at the eldritch plume of glowing plasma that trailed away behind us.
And me? I ought not to say it, but I was rather pleased. I mean, McAndrew had been jealous, jealous of someone I hadn’t much liked at the time and hadn’t seen or heard of in fifteen years. I thought that was rather sweet.
No, it’s not quite the same as fine jewels or bouquets of flowers. But once you forget about his being a genius, McAndrew’s a simple man. When it comes to compliments I settle for what I can get.
McAndrew had known that several of the Arks had been launched far north of the ecliptic when he played me Fogarty’s message. He did the background research before we left, and it was all in the Merganser’s data banks.
I sifted through the material one morning, while McAndrew sat in a habitual stupor of advanced physics and the ship raced out toward the fiery point of the Cassiopeia supernova. The Sun had already shrunk behind us to a point of light and although we were crowding light-speed we didn’t seem to be moving.
There had been seventeen Arks, but only four of them were candidates for what we were seeking. Each of them was different and distinctive. You might expect that. Any group of people which decides to leave the rest of humanity and heads off on a one-way trip to the stars is likely to be a little odd.
The Ark of the Evangelist had set out to spread its version of the Word of God among the stars. It contained four thousand followers of the philosopher Socinus, which was probably all of them. The Word, from what I could see of it in the data base, was likely to baffle any alien who encountered it. Certainly, the Word baffled me.
The Ark of the Evangelist was equipped with unusually powerful communications equipment, able to beam messages ahead so that their ultimate arrival at another stellar system would be expected. The same equipment would, of course, also be able to send messages back toward Sol. None had ever been received, unless Paul Fogarty had picked up the first.
The Cyber Ark had no interest in evangelism. It had headed out toward Cassiopeia, but any direction would have done equally well. The Ark held two thousand computer specialists and the most advanced computing equipment that the Solar System could produce. The Ark ’s inhabitants were united in their disdain for the rules that limited the development of machine intelligence. They had vowed to produce real artificial intelligence, a true AI, and they claimed to know how exactly to do it. Their goal was an AI far beyond the known limits of either humans or machines. If they felt in a generous mood when they were done, well, they just might tell Earth when the work was finished.
Big talk. But if they had been successful, they had sent back no word in the fifty-nine years since they flew away from the Solar System.
Then there was the Ark of Noah. Its colonists had become convinced from their analysis of ancient religious writings that Armageddon and the end of Earth were close to hand. They had no faith in the survival of the colonies we had established on Mars, Titan, or Ceres. Inside the two-kilometer sphere of their ark, formed from a hollowed-out asteroid, they had tried to include a pair of every Earth species of plant and animal. Impossible, in practice — we were up to four million species of insects, and still counting. But the Ark of Noah gave it a good, all-out try, packing in a handful of every life-form they could find. They took liberties with the number of humans, two hundred instead of Noah’s single family; but somebody had to manage the Ark ’s life-support systems, if and when things went out of whack.