Belgian particle physicist Prof. Francis Halzen has been awarded the 2026 Nobel Prize in Physics for his contributions to the IceCube neutrino observatory at the South Pole and the discovery of high-energy neutrinos from astrophysical sources.
Halzen, a researcher at the University of Wisconsin-Madison, led the project that transformed a cubic kilometre of Antarctic ice into a detector for neutrinos, elusive particles that travel through matter with little interaction. The Nobel committee announced the award on Tuesday, citing his “decisive contributions to the IceCube neutrino observatory and the discovery of high-energy neutrinos of astrophysical origin”. The prize carries 12 million Swedish kronor.
Proposed by him in 1988, IceCube uses thousands of basketball-sized light detectors embedded deep in the ice to capture faint flashes produced when neutrinos collide with atomic nuclei. The observatory made its first detection of high-energy neutrinos from beyond Earth in 2013. Scientists later identified a cosmic neutrino source located 3.7 billion light-years away.
Neutrinos are produced by sources such as the Sun and pass through people, planets and other matter largely undetected. Their ability to travel across vast distances makes them valuable tools for studying extreme cosmic events and understanding the evolution of the universe.
Speaking after receiving the news while travelling in Italy, Halzen said he hoped the recognition would also honour the talented people who supported the project in its early stages.
Dr Patrick Dunne of Imperial College London welcomed the award, comparing neutrino astronomy to Galileo’s first observations of the stars through a telescope. He said detecting these particles offers scientists a new way to study distant and extreme phenomena.
IceCube has helped establish neutrino astronomy as a new field alongside observations using light, electromagnetic radiation and gravitational waves. Other major experiments studying neutrinos include the Deep Underground Neutrino Experiment in the United States and Hyper-Kamiokande in Japan.
Halzen said he hoped the Nobel recognition would help secure approval for his next research proposal, adding that neutrino astronomy could lead to unexpected discoveries in the decades ahead.