Belgian-born American scientist Francis Halzen has won the 2026 Nobel Prize in Physics for his leading contributions to the IceCube Neutrino Observatory and the discovery of high-energy neutrinos of astrophysical origin.
The Royal Swedish Academy of Sciences announced the award in Stockholm, recognizing Halzen’s work in developing the IceCube observatory and advancing the study of high-energy neutrinos arriving from the cosmos.
Mark Pearce, chair of the Nobel Committee for Physics, said Halzen led an international team of researchers and engineers in developing an extraordinary scientific instrument. He added that Halzen’s persistence and scientific insight had opened the way to a new form of astronomy.
The 82-year-old Halzen is associated with the University of Wisconsin–Madison. Speaking to the Nobel Committee by telephone after the announcement, he said the news came as a major surprise and that he had not expected it.
The IceCube Neutrino Observatory is a major research facility located at the South Pole in Antarctica and is led by the University of Wisconsin–Madison.
Neutrinos are extremely light fundamental particles that are found throughout the universe. Trillions of neutrinos produced by stars such as the Sun pass through the human body every second, yet they are extraordinarily difficult to detect directly.
Scientists identify neutrinos by detecting the flashes of light or charged particles produced when they interact with matter.
Halzen’s research focused on rare, high-energy neutrinos that can carry information from distant cosmic sources. These particles provide scientists with valuable clues about the evolution of the universe and some of the most energetic astrophysical phenomena.
His work on detecting neutrinos at the South Pole dates back to the 1980s and ultimately contributed to the development of IceCube into a powerful tool for exploring the universe through neutrinos.
The Nobel Prize comes with a total award amount of approximately US$1.2 million this year.