The 2026 Nobel prize for physics has been awarded to Francis Halzen for his discovery of high energy neutrino particles from space.

The Nobel committee said Halzen has made “decisive contributions” to the discovery of “neutrinos of astrophysical origin” with IceCube, an experiment installed under ice at the South Pole.

Ellen Moons, secretary general of the Royal Swedish Academy of Sciences, referred to these neutrinos as “ghostly messengers”. This term refers to the fact the particles have nearly no mass and pass through solid objects with hardly any interaction. In fact, billions of neutrinos pass through any given person on Earth every second.

Most of these neutrinos are emitted by the Sun. However, high energy neutrinos coming from elsewhere in the cosmos also reach our planet. These neutrinos are about a billion times rarer than those that stream out from the Sun.

They originate from diverse sources, such as black holes located at the hearts of distant galaxies that accelerate particles to extreme energies.

The idea for the IceCube experiment was to use the ice at the South Pole as a transparent natural medium to capture the faint flashes of these high energy particles. The experiment comprises thousands of sensors under the frozen surface of Antarctica, distributed over one cubic kilometre.

Commenting on why Halzen’s work is important, Mark Pearce, chair of the Nobel committee for physics, said: “The neutrino has such peculiar properties: the fact that it interacts so infrequently in material – and in this case........

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