Imperial physicists welcome Nobel Prize for breakthrough in neutrino astronomy

The 2026 Nobel Prize in Physics recognises Francis Halzen’s contributions to the IceCube Neutrino Observatory and the discovery of high-energy cosmic neutrinos

The award highlights work that has transformed scientists’ ability to study some of the most extreme environments in the Universe. By observing high-energy neutrinos arriving from distant cosmic sources, IceCube opened an entirely new way of exploring the cosmos and helped establish the field of neutrino astronomy.

For centuries, astronomers have relied on light to study the cosmos. Whether visible light, radio waves, X-rays or infrared radiation, our understanding of the Universe has been built using different forms of electromagnetic radiation.

Neutrinos offer something fundamentally different. Because they rarely interact with matter, they can travel across the cosmos almost entirely undisturbed, carrying information from environments that would otherwise remain hidden.

The Nobel Prize recognises Halzen's vision for using Antarctic ice to detect these high-energy cosmic neutrinos. In 1988, he proposed using the transparent glacial ice at the South Pole as a detector, an idea that would eventually lead to the construction of IceCube.

By transforming a cubic kilometre of Antarctic ice into a giant scientific instrument, the Belgian physicist created an observatory capable of capturing these extremely rare interactions, laying the foundations for the field of neutrino astronomy.

For all of human history the only way we've been able to understand things outside our solar system is with light. Detecting neutrinos from astrophysical sources opens up a new lens, so it isn't overstating things to liken this to when Galileo first pointed a telescope at the stars. Dr Patrick Dunne Department of Physics, Imperial College London

Built deep within the ice of Antarctica, IceCube uses thousands of light sensors embedded in glacial ice to detect the faint flash produced when neutrinos interact with matter. The observatory made the first detection of high-energy extraterrestrial neutrinos in 2013 and later helped identify the first known source of these particles, establishing neutrino astronomy as a practical branch of astronomy.

Dr Patrick Dunne, in Imperial’s Department of Physics, said “For all of human history the only way we've been able to understand things outside our solar system is with light. Detecting neutrinos from astrophysical sources opens up a new lens, so it isn't overstating things to liken this to when Galileo first pointed a telescope at the stars. Neutrinos are the most abundant massive particles and their ability to pass through matter much more easily than light can makes them ideal for observing distant phenomena or the inside of extreme phenomena like those seen by IceCube. 

"Not only are neutrinos excellent tools for astronomy, they might also reveal why the universe exists and point the way to better understanding of fundamental science. On earth we are working hard to understand neutrinos in even more detail through experiments like DUNE and Hyper-Kamiokande."

Imperial’s role in the future of neutrino physics

The Nobel Prize also highlights the growing importance of neutrino research across physics and astronomy. While IceCube uses neutrinos to study distant astrophysical phenomena, researchers around the world are using the particles to investigate some of the deepest questions in fundamental physics.

Imperial has a long-standing involvement in this area of research. Recent work has ranged from studies of cosmic neutrinos in dark matter detectors to searches for hypothetical sterile neutrinos and participation in major international collaborations.   

Professor Stefan Söldner-Rembold, Head of the Department of Physics at Imperial, who previously was a member of the IceCube-Gen2 collaboration, said “The IceCube Neutrino Observatory at the South Pole detects high-energy neutrinos—among the most elusive particles in the subatomic world. Its observations are opening a new era of multi-messenger astronomy, enabling scientists to study distant astrophysical objects through more than one type of physical signal.

 "The Nobel Prize awarded to Francis Halzen recognises his vision and determination in creating this unique experiment and bringing together a major international collaboration. It is also a recognition of the field of astroparticle physics and of the vital role neutrinos play in helping scientists address some of the Universe’s deepest mysteries.”

Among the major projects involving Imperial researchers are the Deep Underground Neutrino Experiment (DUNE) in the United States and Hyper-Kamiokande in Japan, two next-generation experiments that aim to answer some of the remaining questions about these particles, including how they change as they travel and whether they could help explain why matter dominates over antimatter.

Professor Söldner-Rembold added “These experiments will study neutrinos produced by particle accelerators after they have travelled long distances through the Earth. By examining how neutrinos change during their journey, researchers hope to deepen understanding of their fundamental nature—including whether they could help explain why the Universe contains more matter than antimatter.

 "DUNE and Hyper-Kamiokande will also detect neutrinos emitted by supernovae, providing a rare window into some of the most violent events in the Universe."