Francis Halzen wins physics Nobel for South Pole neutrino observatory

Francis Halzen has won the Nobel Prize in Physics for helping turn a cubic kilometre of Antarctic ice into a telescope for particles from distant galaxies. His work on the IceCube Neutrino Observatory has given scientists a way to study violent events in the universe that ordinary telescopes cannot easily see.

The Royal Swedish Academy of Sciences announced the prize Tuesday in Stockholm, recognizing Halzen’s contributions to IceCube and the discovery of high-energy neutrinos that originate beyond Earth. The observatory sits at the South Pole, where light sensors embedded in the ice look for brief flashes left by the elusive particles.

“Francis Halzen has led an international team of researchers and engineers who have provided us with a fantastic instrument,” Mark Pearce, chair of the Nobel Committee for Physics, said in a statement. “His tenacity and scientific vision has paved the way for a new kind of astronomy.”

Neutrinos are subatomic particles that pass through matter with little effect. The sun produces them in enormous numbers: billions pass through an area the size of a fingernail every second, according to the BBC. IceCube, however, searches for much higher-energy neutrinos produced by extreme processes far beyond the solar system, including in distant galaxies.

Most of those particles pass straight through the Antarctic ice. Occasionally, one interacts with it, producing other particles and a telltale flash of light that IceCube’s sensors can detect. Those rare signals offer clues to the neutrino’s origin and to the conditions that produced it.

Halzen first presented his vision for detecting neutrinos at the South Pole in 1988, the BBC reported. The Royal Swedish Academy of Sciences said “his vision and scientific leadership have been fundamental for the IceCube Neutrino Observatory.” The University of Wisconsin–Madison, where Halzen is affiliated, is IceCube’s lead institution, according to NPR.

Speaking to the Nobel committee by phone from Italy on Tuesday, Halzen said the award came as a surprise. “It was a great surprise and I obviously didn’t expect it,” he said. NPR reported that the Belgian-born scientist, 82, said he had previously been predicted to win the prize but still found the announcement “strange.”

This year’s Nobel prize money is 12 million Swedish kronor, about $1.2 million, NPR reported. The physics announcement followed Monday’s medicine prize; prizes in chemistry, literature and peace are scheduled later this week, with the economics prize to follow Monday.