Nebular Friction

(Alpha and Beta Centauri.)

"A Sun Invisible."

I had forgotten some details. When Falkayn deduces that Beta Centauri had captured a cluster of rogue planets, Beljagor objects that single bodies cannot make captures. (V, p. 301) So it must have happened when the star was still condensing. Beta's gravity deflected the planets, then friction with its nebular cloud slowed them down so that their hyperbolic orbits became elliptical albeit eccentric. Possibly also, a secondary center of condensation, later spiraling into the main mass, had helped to decelerate and capture the planets.

Although these Beta Centaurian planets "'...were sterile, with poisonous atmospheres...,'" (V, p. 302) the Kraoka:

converted their atmospheres by seeding them with photosynthetic spores;
released life forms that consumed primeval organic matter and initiated ecologies;
thus, created conditions in which microbes multiplied exponentially;
thus, further, made the planets habitable in a few centuries.

This post describes two processes, the first preceding any intervention by conscious beings.