"We're Heaven knows where," he said dourly. "Somebody really messed us up! The only star that shows parallax isn't Merida. In fact, I don't believe in it at all. Two plates show it as a Sol-class sun and the third says it's a red dwarf!"
On the face of it, such a thing was impossible. A sun cannot be one color as seen from one spot, and another color seen from another. Especially when the shift of angle is small.
Calhoun made rough computations. He hand-set the overdrive for something over an hour's run in the direction of the one star-image which wobbled and thereby beckoned. He threw the switch. He gulped, and Murgatroyd acted for a moment as if he intended to yield unreservedly to the nausea of entering overdrive, but he refrained.
There was nothing to do but kill time for an hour. There was a microreel of starplates, showing the heavens as photographed with the same galactic coordinates from every visited Sol-class star in this sector of the galaxy. Fewer than one in forty had a colonized planet, but if the nearest had been visited before, and if the heavens had been photographed there, by matching the stars to the appropriate plate he could find out where he was. Then a star-map might begin to be of some use to him. But he had still to determine whether the error was in his astrogation unit, or in the data fed to it. If the first he'd be very bad off indeed. If the second he could still be in a fix. But there was no point in worrying while in overdrive. He lay down on his bunk and tried to concentrate again on the book he'd laid aside.
"Human error, moreover," he read, "is never purely random. The mind tends to regard stored data as infallible and to disregard new data which contradicts it . . . ." He yawned, and skipped. " . . . So each person has a personal factor of error which is not only quantitative but qualitative . . . ."
He read on and on, only half absorbing what he read. A man who has reached the status of a Med Ship man in the Interstellar Medical Service hasn't finished learning. He's still a way down the ladder of rank. He has plenty of studying before him before he gets very far.
The tape-speaker said, "When the gong sounds, breakout will be five seconds off." It began to tick-tock, slowly and deliberately. Calhoun got into the control-seat and strapped in. Murgatroyd said peevishly, "Chee!" and went to position underneath the chair. The voice said, "Five—four—three—two—one."
The little Med Ship came out of overdrive, and instantly its emergency rockets kicked violently and Murgatroyd held desperately fast. Then the rockets went off. There'd been some unguessable nearby, perhaps cometary debris at the extremist outer limit of a highly eccentric orbit. Now there was a star-field and a sun within two light-hours. If Calhoun had stared, earlier, when there was no sun in sight at all, now he gazed blankly at the spectacle before him.
There was a sun off to starboard. It was a yellow sun, a Sol-type star with a barely perceptible disk. There were planets. Calhoun saw immediately one gas-giant near enough to be more than a point, and a sliver of light which was the crescent of another more nearly in line toward the sun. But he gazed at a belt, a band, a ribbon of shining stuff which was starkly out of all reason.
It was a thin curtain of luminosity circling this yellow star. It was not a ring from the break-up of a satellite within Roche's Limit. There were two quite solid planets inside it and nearer to the sun. It was a thin, wide, luminous golden ribbon which looked like something that needed a flat iron to smooth it out. It looked somewhat like an incandescent smoke ring. It was not smooth. It had lumps in it. There were corrugations in it. An unimaginable rocket with a flat exhaust could have made it while chasing its tail around the sun. But that couldn't have happened, either.
Calhoun stared for seconds.
"Now," he said, "now I've seen everything!" Then he grunted as realization came. "Mmmmh! We're all right, Murgatroyd! It's not our computers that went wrong. Somebody fed them wrong data. We arrived where we aimed for, and there'll be a colonized planet somewhere around."
He unlimbered the electron telescope and began a search; he couldn't resist a closer look at the ribbon in space. It had exactly the structure of a slightly wobbly wrinkled belt without beginning or end. It had to be a complex of solid particles, of course, and an organization of solid particles cannot exist in space without orbital motion. However, orbits would smooth out in the course of thousands of revolutions around a primary. This was not smoothed out. It was relatively new.
"It's sodium dust," said Calhoun appreciatively. "Or maybe potassium. Hung out there on purpose. Particles small enough to have terrific surface and reflective power, and big enough not to be pushed out of orbit by light-pressure. Clever, Murgatroyd! At a guess it'll have been put out to take care of the climate on a planet just inside it. Which would be—there! Let's go look!"
He was so absorbed in his admiration that the almost momentary overdrive-hop needed for approach went nearly unnoticed. He even realized—his appreciation increasing—that this cloud of tiny particles accounted for the red dwarf appearance on one of the plates he'd taken. Light passing through widely dispersed, very small particles turns red. From one position, he'd photographed moving through this dust cloud.
The ribbon was a magnificent idea, the more magnificent because of its simplicity. It would reflect back otherwise wasted sun-heat to a too-cold planet and make it warmer. There was probably only an infinitesimal actual mass of powder in the ring, at that. Tens of scores of tons in all, hardly more.
The planet for which it had been established was the third world out. As is usual with Sol-class systems, the third planet's distance from the sun was about a hundred twenty million miles. It had ice caps covering more than two-thirds of its surface. The sprawling white fingers of glaciation marked mountain chains and highlands nearly to the equator. There was some blue sea, and there was green vegetation in a narrow belt of tropicality.
Calhoun jockeyed the Med Ship to position for a landing call. This was not Merida II; there should be a colony here! That glowing ribbon had not been hung out for nothing.
"Med Ship Aesclipus Twenty," he said confidently into the space-phone mike. "Calling ground. Requesting coordinates for landing. My mass is fifty tons. Repeat, five-oh tons. Purpose of landing, to find out where I am and how to get where I belong."
There was a clicking. Calhoun repeated the call. He heard murmurings which were not directed into the transmitter on the planet. They were speaking in the transmitter room aground. He heard an agitated: "How long since a ship landed?" Another voice was saying fiercely, "Even if he doesn't come from Two City or Three City, who knows what sickness . . ." There was sudden silence, as if a hand had been clapped over the microphone below. Then a long pause. Calhoun made the standard call for the third time.
"Med Ship Aesclipus Twenty," said the space-phone speaker grudgingly, "you will be allowed to land. Take position." Calhoun blinked at the instructions he received. The coordinates were not the normal galactic ones. They gave the local time at the spaceport, and the planetary latitude. He was to place himself overhead. He could do it, of course, but the instructions were unthinkable. Galactic coordinates had been used ever since Calhoun knew anything about such matters. But he acknowledged the instructions. Then the voice from the speaker said truculently: "Don't hurry! We might change our minds! And we have to figure settings for an only fifty-ton ship, anyhow."