Francis Halzen wins Nobel Prize in Physics for work on ‘ghost particles’

What the report says

Belgian physicist Francis Halzen has won the 2026 Nobel Prize in Physics, according to the Royal Swedish Academy of Sciences in Stockholm. Al Jazeera reported that the award recognizes his leading role in developing the IceCube Neutrino Observatory in Antarctica, a large detector designed to capture neutrinos, often described as “ghost particles,” from space.

The observatory uses the clear ice beneath the South Pole to help detect faint flashes of light that can appear when a neutrino interacts with an atomic nucleus. Those measurements help scientists study high-energy particles and may provide clues about how the universe evolved, including the behavior of distant galaxies, exploding stars and black holes. The Academy said the work could also point to previously unknown phenomena.

Halzen, who is 82, said in a phone call broadcast during the announcement that the result was a surprise. He noted that he is still working on a proposal he hopes the recognition will help advance. The report also said he first proposed the IceCube project in 1988, and that the effort involved many contributors even though his role was central.

Beyond the specific award, the Nobel physics prize is part of the annual Stockholm announcements that culminate in the Nobel ceremonies on December 10. The result highlights how neutrino astronomy has become a tool for studying the cosmos in ways other observations cannot.