t for the runners.

The scout lay back on his miniature island and stared up into the sky,
trying to sort out all the myriad impressions of life about him. It
was then that he saw it....

An arrow of fire streaking across the black bowl of Astra's night sky.
A light so vivid, so alien, that it brought him to his feet with a
chill prickle of apprehension along his spine. In all his years as a
scout and woodsman, in all the stories of his fellows and his elders
at Homeport--he had never seen, never heard of the like of that!

And through his own wonder and alert alarm, he caught Sssuri's added
puzzlement.

"Danger--" The merman's verdict fed his own unease.

Danger had crossed the night, from east to west. And to the west lay
what they had always feared. What was going to happen now?

2

PLANETFALL

Raf Kurbi, flitter pilot and techneer, lay on the padded shock cushion
of his assigned bunk and stared with wide, disillusioned eyes at the
stretch of stark, gray metal directly overhead. He tried to close his
ears to the mutter of meaningless words coming from across the narrow
cabin. Raf had known from the moment his name had been drawn as crew
member that the whole trip would be a gamble, a wild gamble with the
odds all against them. _RS 10_--those very numbers on the nose of the
ship told part of the story. Ten exploring fingers thrust in turn out
into the blackness of space. _RS 3_'s fate was known--she had
blossomed into a pinpoint of flame within the orbit of Mars. And _RS
7_ had clearly gone out of control while instruments on Terra could
still pick up her broadcasts. Of the rest--well, none had returned.

But the ships were built, manned by lot from the trainees, and sent
out, one every five years, with all that had been learned from the
previous job, each refinement the engineers could discover
incorporated into the latest to rise from the launching cradle.

_RS 10_--Raf closed his eyes with weary distaste. After months of
being trapped inside her ever-vibrating shell, he felt that he knew
each and every rivet, seam, and plate in her only too well. And there
was no reason yet to believe that the voyage would ever end. They
would just go on and on through empty space until dead men manned a
drifting hulk--

There--to picture that was a danger signal. Whenever his thoughts
reached that particular point, Raf tried to think of something else,
to break the chain of dismal foreboding. How? By joining