compounds, and had nuggets of heavier elements scattered through it like raisins in a plum pudding. Around it for thousands of miles there extended a tenuous halo of the more volatile of its constituent compounds. The thing was moving away from the Sun in an elliptical orbit, showing no sign of intelligent control. A portion of its gaseous envelope was driven on ahead by the pressure of sunlight from below.
It was a dead slave, but it could as easily have been a dead master. A dead slave was nothing; but the thing that had killed it could do the same to him.
It was the first time in his incredibly long life that the personal possibility of death had struck home to him; and probably nothing less than that fear could have saved his life.
With the student close beside, he followed the weirdly glowing corpse out to the farthest point of its orbit; and as it started to fall back into the halo of death girdling that harmless-looking star, he pressed on out into the friendly darkness.
Perhaps some day that third planet would be harvested; but it would not be by one of his kind — not, at least, until that guarding haze had been swept up by the planets that drifted through its protecting veil.
It was not a very good group, Wright reflected. That always seemed to be the case. When he had luck with observing weather, he had no one around to appreciate the things that could be seen. He cast a regretful glance toward the dome of the sixty-inch telescope, where a fellow candidate was taking another plate of his series, and wondered whether there were not some better way than part-time instructing to pay the expenses of a doctorate program.
Still, the night was good. Most of the time in the latitude—“Mr. Wright! Is that a cloud or the Aurora?”
“If you will stop to consider the present position of the Sun below the horizon,” he answered indirectly, “you will discover that the patch of light you are indicating is directly opposite that point. It lies along the path of the Earth's shadow, though, of course, well beyond it. It is called the Gegenschein and, like the Zodiacal Light, is not too commonly visible at this latitude. We did see the Light some time ago, if you remember, on an evening when we started observing earlier. Actually, the Gegenschein is a continuation of the luminous band we call the Zodiacal Light. The latter can sometimes be traced all the way around the sky to the point we are now watching.”
“What causes them?”
“The most reasonable assumption is that they are light reflected from small, solid particles — meteors. Apparently a cloud of such matter extends outward for some distance past the Earth's orbit, though just how far, it is hard to say. It grows fainter with distance from the Sum, as would be expected, except for the patch we call the Gegenschein.”
“Why the exception?”
“I think one of you can answer that.”
“Would it be for the same reason that the full Moon is so much more than twice as bright as either quarter? Simply because the particles are rough, and appear dark in most positions because of the shadows of irregularities on their own surfaces — shadows which disappear when the light is behind the observer?”
“I think you will agree that that would account for it,” Wright said. “Evidently the meteors are there, are large compared to wavelengths of visible light, and form a definite part of the Solar System. I believe it was once estimated that if the space inside the Earth's orbit contained particles one millimeter in diameter and five miles apart, they would reflect enough light to account for what we are observing. They might, of course, be smaller and more numerous. Only that amount of reflecting surface is necessary.”
“You had me worried,” another voice broke in. “I'd been hearing for years that there would be little reason to fear collisions with meteors when we finally get a rocket out of the atmosphere. For a moment, I though a cloud such as you were working up to would riddle anything that got into space. One pinhead every five miles isn't so bad, though.”
“There is a fairly good chance of collision, I would say,” returned Wright, “but just what damage particles of that size would do, I am not sure. It seems rather likely that they would be volatilized by impact. How the hull of a rocket would react, we will have to find out by experience. I wouldn't mind taking the risk myself. I think we can sum up the greatest possibilities by saying that the meteoric content of the Solar System has and will have nothing but nuisance value to the human race, whether or not we ever leave our own planet.”
A streak of white fire arced silently across the sky, putting a fitting period to the subject.
Wright wondered whether it would appear on his friend's photographic plate.
The Foundling Stars
“All right — perfect. You're the most nearly motionless thing in the universe.”
Hoey's words were figurative, of course; whether they were accurate or not depended entirely on point of view. Rocco Luisi and his
How long this would last was problematical. An automatic tracker was now on duty in Hoey's ship, trying to hold steady the fringe pattern produced by combining two ultraviolet laser beams, one originating in his own vessel and the other in Luisi's, in one of the most precise interferometers ever made. Since the crafts were about a light-hour apart, however, corrections tended to be late in time and, in spite of a computer's best efforts, erratic in amount and direction.
“Nineteen decimals” had been a proverbial standard of accuracy for well over a century; but achieving it on any but the atomic size and time scale was not yet standard art.
“That seems to be it,” Hoey repeated. “That means that you and I stay strapped in our seats, with no more motion than we can help, for the next four hours or so. If either of the instrument platforms on our ships moves more than half a micron with respect to the other, a lot of time and money go down the drain.”
“I know — I've had it hammered into me as often and as hard as you have.” Luisi's voice was undistorted, and the responses instant, on the medium communicator.
“Sure you have,” retorted Hoey, “only a lot of people wonder whether you really believe it.”
“Well, it depends on what you mean by believe. I can figure as well as anyone where the center of mass of my ship would go if I stood up; I…'
“I know you can. Your trouble
“Right there I break connection. Space is space. You only worry about wind when you're close to a sun, and then it's only a hard-radiation problem.”
“True enough, as a rule. The trouble is that the usual run of stellar winds involves a mass density of around ten atoms to the cubic centimeter; here it's a couple of thousand. It turned out that even that much mass wouldn't accelerate the ships seriously unless the relative velocity were very high indeed, but it was something the planners had to check on. You see what I mean; so stay put. Let's cut the chatter. The sooner the folks in 'Big Boy' can get to work, the sooner we can breathe comfortably. I'll call 'em.”
Hoey's finger tensed on a button, replacing the microscopic crystal in the activity field of his communicator with another, whose twin was aboard. “Big Boy” — more formally, the
'We're in position, and my tracker says we're holding. Get the job going while the going's good.”
“Right.” The answer was terse, but not casual. The speaker, a heavy-set, middle-aged man with an almost fanatically intense stare in his blue eyes, leaned forward over the console in front of him and began punching buttons in an intricate sequence. He paused every second or two to interpret the patterns of light which winked at