Complex sentence: Lazar, who is affiliated with the Highland Road Park Observatory, where she co-discovered asteroid 20430 Stout with Walter R. Cooney, Jr. at age 16 and named it after her late great-grandfather Earl Douglas Stout (c.1895--1985).
Split into simpler sentences: Lazar, who is affiliated with the Highland Road Park Observatory, where she co-discovered asteroid 20430 Stout with Walter R. Cooney, Jr. at age 16. She named one of her discoveries after her late great-grandfather Earl Douglas Stout (1895?--1985).