Because these were to go out to airlessness. The miniature grid could lift and hold a bomb steady in its field-focus at seven hundred and fifty thousand feet. But if a bomb was accelerated all the way out to that point, and the field was then snapped off.... Why, it wasn't held anywhere! It kept on going with its attained velocity. And it burst when its fuse decided that it should, whereupon immediately a mass of sodium and potassium vapor, mixed with the fumes of high explosive, flung itself madly in all directions, out between the stars. Absolute vacuum tore the compressed gasified metals apart. The separate atoms, white-hot from the explosion, went swirling through sunlit space. The sunlight was dimmed a trifle, to be sure. But individual atoms of the lighter alkaline-earth metals have marked photoelectric properties. In sunshine these gas-molecules ionized, and therefore spread more widely, and did not coalesce into even microscopic droplets.
They formed, in fact, a cloud in space. An ionized cloud, in which no particle was too large to be responsive to the pressure of light. The cloud acted like the gases of a comet's tail. It was a comet's tail, though there was no comet. And it was an extraordinary comet's tail because it is said that you can put a comet's tail in your hat, at normal atmospheric pressure. But this could not have been put in a hat. Even before it turned to gas, it was the size of a basketball. And, in space, it glowed.
It glowed with the brightness of the sunshine on it, which was light that would normally have gone away through the interstellar dark. And it filled one corner of the sky. Within one hour it was a comet tail ten thousand miles long, which visibly brightened the daytime heavens. And it was only the first of such reflecting clouds.
The next bomb set for space exploded in a different quarter, because Bordman had had the miniature grid wrestled around the upcrop to point in a new and somewhat more carefully chosen line. The next spattered brilliance in a different section still. And the brilliance lasted.
Bordman flung his first bombs recklessly, because there would be more, and because he was desperately anxious to hang as many comet-tails as possible around the colony-planet before nightfall. He didn't want it to get any colder.
And it didn't. In fact, there wasn't exactly any real nightfall on Lani III that night.
The planet turned on its axis, to be sure. But around it, quite close by, there hung gigantic streamers of shining gas. At their beginning, those streamers bore a certain resemblance to the furry wild-animal tails that little boys like to have hanging down from hunting-caps. Only they shone. And as they developed they merged, so that there was an enormous shining curtain about Lani III, draperies of metal-mist to capture sunlight that would otherwise have been wasted, and to diffuse much of it on Lani II. At midnight there was only one spot in all the night sky where there was really darkness. That was overhead, directly outward from the planet, opposite from the sun. Gigantic shining streamers formed a wall, a tube, of comet-tail material, yet many times more dense and therefore more bright, which shielded the colony world against the dark and cold, and threw upon it a shining, warming brightness.
Riki maintained stoutly that she could feel the warmth from the sky, but that was improbable. However, heat certainly did come from somewhere. The thermometer did not fall at all, that night. It rose. It was up to fifty below zero at dawn. During the day—they sent out twenty more bombs that second day—it was up to twenty degrees below zero. By the day after, there were competent computations from the home planet, and the concrete results of abstruse speculation, and the third day's bombs were placed with optimum spacing for heating purposes.
By dawn of the fourth day the air was a balmy five degrees below zero, and the day after that there was a small running stream in the valley at midday.
There was talk of stocking the stream with fish, on the morning the Survey ship came in. The great landing-grid gave out a deep-toned, vibrant, humming note, like the deepest possible note of the biggest organ that could be imagined. A speck appeared high up in a pale-blue sky with trimmings of golden gas clouds. The Survey ship came down and down and settled as a shining silver object in the very center of the gigantic red-painted landing-grid.