In her calm, deliberate way, astrophysicist Jocelyn Bell Burnell has always been in the business of changing worlds. Over a storied four-decade career, she has helped expand our understanding of the universe, caused people to rethink how Nobel Prizes are awarded, and used her stature to fight sexism in the world of science.

Burnell made her first scientific mark in 1968 as Jocelyn Bell, an unknown, 23-year-old doctoral student from Northern Ireland. After months of using the new radio telescope at the University of Cambridge, she came upon inexplicable, metronomically regular radio blips from isolated spots in the sky. Bell and her Ph.D. supervisor, Antony Hewish, concluded that the blips came from hitherto unknown objects, massive yet remarkably small. Because of their pulsed signals, these objects were dubbed pulsars. Soon after, pulsars were identified as rapidly spinning neutron stars, the remnants of supernova explosions; they weigh as much as the sun but are just a dozen miles wide. The discovery was so significant that the Nobel Committee recognized it with a share of the 1974 prize in physics—an honor that was presented to Hewish but not to the young woman who had made the initial observation, Jocelyn Bell. The snub made international news.

Time magazine hyped it as “A Nobel Scandal?” But Burnell was philosophical. “I believe it would demean Nobel Prizes if they were awarded to research students, except in very exceptional cases,” she later said, “and I do not believe this is one of them.... I am not myself upset about it—after all, I am in good company, am I not?”