Nobel Prize in physics goes to scientist who turned Antarctic ice into a 'ghost particle' telescope

Francis Halzen, a physicist at the University of Wisconsin-Madison, won the 2026 Nobel Prize in physics Tuesday for helping turn a block of Antarctic ice into the world's largest neutrino telescope.

The Royal Swedish Academy of Sciences honored the 82-year-old Belgian-born scientist "for decisive contributions to the IceCube Neutrino Observatory and the discovery of high-energy neutrinos of astrophysical origin," according to the Nobel Prize announcement. The prize is worth 12 million Swedish kronor, about $1.2 million, according to Fox 11 and Physics World.

## What are neutrinos?

Neutrinos are tiny particles with almost no mass and no electric charge. Trillions of them pass through your body every second without you noticing, because they rarely interact with anything.

That makes them hard to catch, but also useful. Light from distant objects can be blocked or bent on its way to Earth. Neutrinos travel in a straight line, so the ones that reach us carry clues straight from some of the most violent places in the universe, such as the areas around supermassive black holes.

## A telescope made of ice

Halzen's idea was to use the clear, deep ice at the South Pole as a detector. When a neutrino does hit something in the ice, it produces a faint flash of blue light.

The IceCube Neutrino Observatory, completed in December 2010, has 5,160 light sensors hung on 86 cables in holes drilled 1,450 to 2,450 meters deep, according to IceCube. Together they watch about a cubic kilometer of ice near the Amundsen-Scott South Pole Station.

The project is run by an international collaboration led from UW-Madison and funded by the U.S. National Science Foundation, the university said.

## What it found

In 2013, IceCube reported the first detection of high-energy neutrinos from beyond our solar system, according to UW-Madison. Later results traced neutrinos to an active galaxy about 47 million light-years away and found the first evidence of high-energy neutrinos coming from our own Milky Way, the university said.

"This is a celebration of a very unusual project," Halzen said in a UW-Madison statement. "It is difficult to imagine that we could have pulled this off anywhere but at UW-Madison with its unique research infrastructure."

## Reaction

Speaking by phone from Italy during the announcement, Halzen said, "It was a great surprise, and I obviously didn't expect it," according to Fox 11. He added that he is working on a new proposal and hopes the prize "will help getting it approved."

Michael Moloney, CEO of the American Institute of Physics, called the work "a revolutionary way of understanding the universe that we didn't have before."

Halzen is UW-Madison's 23rd Nobel laureate connection and its sixth in physics, according to the university.

## What it means for you

IceCube is a reminder that big science often depends on long-term public funding: the observatory took seven Antarctic summers to build and has run for more than 15 years with National Science Foundation support. Students in physics, engineering, computer science and data analysis work on projects like this, and many large research collaborations recruit undergraduates and graduate students.

## What happens next

Halzen will receive the prize at a ceremony in Stockholm on Dec. 10. The Nobel announcements continue this week with chemistry, literature and peace.