Francis Halzen, a Belgian-born physicist and professor at the University of Wisconsin–Madison, was awarded the 2026 Nobel Prize in Physics on Tuesday for his groundbreaking work on the IceCube Neutrino Observatory, the Royal Swedish Academy of Sciences said. The Academy specifically cited his role in establishing the detector at the South Pole, stating he received the award “for decisive contributions to the IceCube Neutrino Observatory and the discovery of high-energy neutrinos of astrophysical origin.”
IceCube breakthrough
Halzen recognized that the ice sheet at the South Pole could serve as a massive detector for neutrinos — subatomic particles produced by the most energetic phenomena in the distant universe — a vision considered “fundamental” to the creation of the IceCube facility. The observatory consists of a cubic kilometre of Antarctic ice equipped with sensitive light sensors designed to capture the faint flashes created when neutrinos interact with matter, allowing researchers to track particles from deep space.
Unlike light or other forms of radiation, extremely high-energy neutrinos travel across the universe without changing direction or losing significant energy, enabling scientists to gather information about distant astrophysical processes that remain invisible to conventional telescopes. This property allows IceCube to observe cosmic accelerators such as black holes and exploding stars directly, opening a new field of neutrino astronomy.
About the laureate
Halzen was born in Belgium in 1944 and has served as a professor at the University of Wisconsin–Madison in the United States. The Nobel Prize in Physics, first awarded in 1901, recognizes breakthroughs that have conferred the greatest benefit to humankind in the field of physical sciences.