Dragonquest (Dragonriders of Pern)

Since Lessa and Ramoth, her golden queen dragon, traveled into the past to bring forward a small army of dragons and riders to save their world from deadly alien spores, fear and desperation have spread across the land. But while the dragonriders struggle with threats both otherworldly and human, a young rider named F’nor and his brown dragon, Canth, hatch a bold plan to destroy the alien scourge at its source—the baleful red star that fills the heavens and promises doom to all.