The Yonderfolk

Poul Anderson, World Without Stars, Chapter III.

Some intergalactics with an unpronounceable name who breathe hydrogen and drink liquid ammonia (like the Jovians in Three Worlds To Conquer?) have contacted human civilization. The co-owners of Felipe Argens' ship, the Meteor, hope to trade for new scientific knowledge, insights, ideas or art forms. These Yonderfolks' knowledge of the intergalactic stars might lead to other planets profitable for human beings while their sheer difference has implications for what else they might know.

Large hydrogen clouds condensed into galaxies but did not leave an absolute vacuum between them, especially not in the earliest period when the universe had not yet expanded very far. Smaller intergalactic condensations became star clusters. Then, supernovae enriched the interstellar medium, thus producing second and third generation stars. Galactic gravity broke up the clusters. Matter dispersed so far that star formation ceased. The brighter stars burned out, leaving widely scattered, old, metal-poor, red dwarfs, each lasting for fifty billion years on the main sequence.

The Yonderfolk might have got beyond the Stone Age by experimenting with electrostatics, voltaic piles or ceramics. Ceramic tubes filled with electrolytic solution for conductors might have given them electrodynamics. Then, perhaps after millions of years of civilization, they would extract light metals from ores. Even with the space jump, they avoided galaxies because they cannot stand the radiation. Heavily screened, they reached the galactic rim and a planet like their own but with a factor from the company owning the Meteor. The language barrier was more difficult than usual.