Dragonriders of Pern

Dragonriders of Pern is a science fiction series written primarily by American-Irish author Anne McCaffrey, who initiated it in 1967. Beginning 2003, her middle child Todd McCaffrey has written Pern novels, both solo and jointly with Anne. The series (as of June 2011) comprises 22 novels and several short stories. Most of the short fiction has been collected in two volumes or incorporated in one of the novels, so Dragonriders of Pern is sometimes identified with the 24 books. Two of the novellas included in the first novel, Dragonflight, made McCaffrey the first woman to win a Hugo or Nebula Award.

Life on Pern as presented in the novels resembles a pre-industrial society with lords, holds, harpers (musicians, entertainers, and teachers), and dragons, with the occasional examples of higher technology (like flamethrowers, telegraphs, chemical fertilizers, and powerful microscopes and telescopes).

Pernese people are described as belonging to four basic groups: Weyrfolk (including Dragonriders) who live in the Weyrs, the Holders who live in the Holds (cities, towns and farms), the crafters who live in Crafthalls (or are assigned to work their crafts in certain Holds), and the Holdless who have no permanent home (including traders, displaced Holders, and brigands).

One of the main threats to Pernese civilization in the series is Thread, which is described as a mycorrhizoid spore that periodically rains down on the planet due to the orbit of the Red Star. The Red Star is set out to be a rogue planet in the Rukbat system. The Red Star, characterized as a "Sedna-class inner Oort cloud object", has a 250 Turn (or Pernese year) elliptic orbit around its sun. Thread can reach the planet Pern for about 50 Turns while the Red Star is at perihelion. Thread is described in this series as an agent that consumes organic material at a voracious rate, including crops, animals, and any humans in its path.

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