Francis Halzen won the Nobel Prize in physics on Tuesday for his contributions to the IceCube Neutrino Observatory and his discovery of high-energy neutrinos of astrophysical origin.

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

“It was a great surprise and I obviously didn’t expect it,” Halzen said, speaking to the committee by phone from Italy, in a call broadcast at the news conference to announce the winner.

Halzen said it was predicted before that he would win the Nobel Prize but the announcement still made him feel “strange.”

“I’m working on a proposal and I hope winning this will help getting it approved,” he said to chuckles.

Born in Belgium, the 82-year-old scientist is affiliated with the University of Wisconsin–Madison in the U.S. Efforts by The Associated Press to reach him were not immediately successful.

The IceCube Neutrino Observatory is a research facility located at the South Pole in Antarctica, according to its website, and the University of Wisconsin–Madison is its lead institution.

Neutrinos are tiny cosmic particles with a mind-bogglingly small mass. Yet they are everywhere: they spew from stars like the sun and trillions zip through our bodies every second.

Scientists can’t glimpse the mysterious ghost particles zooming around on their own. Instead, they measure what happens when the tiny particles collide with other bits of matter, producing flashes of light or charged particles.

Halzen studied a rare gang of neutrinos that scientists consider messengers from the cosmos, offering clues to how the universe evolved.

His research into capturing neutrinos at the South Pole dates back to the 1980s.

The Royal Swedish Academy of Sciences announced the award in Stockholm.

The prize money this year is 12 million Swedish kronor (about $1.2 million), whether for an individual, a small group of laureates or an organization.

Last year, three scientists won the Nobel Prize in physics for research on the strange behavior of subatomic particles called quantum tunneling that enabled the ultrasensitive measurements achieved by MRI machines and laid the groundwork for better cellphones and faster computers.

The announcements of this year’s prizes began Monday with the Nobel Prize in medicine being awarded to three scientists whose work led to a tool that uses light to help unravel how the brain works.

This week’s awards continue Wednesday with the chemistry prize and literature on Thursday. After Friday’s peace prize is awarded, the Nobel Memorial Prize in Economic Sciences will be announced on Monday.

The prize money this year is 12 million Swedish kronor (about $1.2 million), whether for an individual, a small group of laureates or an organization.