By clarifying the differences among various types of exploding stars, Filippenko enabled them to be used to measure the expansion of the universe.
UC Berkeley supernova and black hole expert Alex Filippenko will share the 2026 Gruber Cosmology Prize, which was announced today (May 19) by the Gruber Foundation.
The prize, one of the most prestigious awards for research on the origin and fate of the universe, comes with $500,000 to be shared equally with Filippenko’s two co-winners, theoretical physicists Ken’ichi Nomoto of the University of Tokyo and Stanford Woosley of UC Santa Cruz.
The scientists were cited for “transforming supernovae from poorly understood stellar explosions into the basis for a quantitative, predictive and empirically validated framework.”
An astrophysicist, professor of astronomy and one of Berkeley’s most popular teachers, Filippenko played a major role in clarifying the varieties of Type Ia supernovae, allowing these exploding stars to be standardized so that their intrinsic brightness could be used to measure the expansion of the universe. He also was cited for discovering two other variants of Type I supernovae.
“I’m honored, though I can think of numerous other astronomers in this field who are equally deserving,” Filippenko said.
At different times, he was a member of two groups of scientists that, in 1998, announced the expansion of the universe was speeding up, leading to the idea that a mysterious dark energy permeates the universe and is fueling the accelerated expansion. The 2011 Nobel Prize in Physics was awarded to the leaders of the two groups — Berkeley physicist Saul Perlmutter and American-Australian astronomer Brian Schmidt — and to Adam Riess, a postdoctoral fellow in Filippenko’s group at the time the research was conducted.
According to the Gruber Prize citation, Filippenko, Nomoto and Woosley’s “trailblazing work links stellar evolution, explosive nucleosynthesis, the origin of heavy elements and the chemical evolution of the universe and supports the use of supernovae for precision cosmology.”