Belgian-US Researchers Win Nobel Prize in Physics for Antarctic Ghost Particle Discovery

The 2026 Nobel Prize in Physics has been awarded to Francis Halzen, a Belgian astrophysicist at the University of Wisconsin–Madison, for his pioneering work on the IceCube Neutrino Observatory in Antarctica, Kompas.com reported on Tuesday (6/10/2026). Halzen developed the deep-ice observatory to detect high-energy cosmic neutrinos, subatomic particles that travel across the universe without stopping and allow scientists to peer into distant galaxies, exploding stars, and environments surrounding black holes.

Francis Halzen Wins 2026 Nobel Prize for Antarctic Neutrino Observatory

Committee members and international colleagues recognized Halzen for designing a method to track “ghost particles” using the clear glacial ice at the South Pole. According to Antara News, the 82-year-old physicist first proposed embedding a vast network of optical sensors deep inside Antarctic ice in 1988. Construction on the massive detector eventually reached completion in 2011, paving the way for the historic 2013 discovery of cosmic neutrinos originating far outside our solar system.

Reacting to the announcement during a press conference covered by Reuters, Halzen expressed profound relief after decades of waiting. “This is very reassuring for me because I have actually been waiting for this for quite a long time,” Halzen said. Belgian Prime Minister Bart De Wever also congratulated the laureate, noting that Halzen dedicated his life to uncovering cosmic secrets through the universe’s tiniest messengers.

How IceCube Detects Ghost Particles Beneath the South Pole

Neutrinos earn their nickname because they carry no electrical charge, possess an extremely tiny mass, and pass straight through planets, stars, and human bodies without leaving a trace. Republika reported that because these particles rarely interact with ordinary matter, scientists cannot observe them directly. Instead, researchers must wait for a neutrino to collide with an atomic nucleus inside a massive detector.

To solve this physics challenge, Halzen realized that the pristine, transparent ice sheet at the South Pole could serve as a giant detector. Antara News noted that when a neutrino collides with a nucleus inside the glacial ice, it produces a faint flash of blue light. IceCube utilizes 5,160 optical sensors distributed across 86 cables drilled up to 2.5 kilometers deep into a one-cubic-kilometer block of ice. This deep burial protects the equipment from cosmic ray interference and allows sensitive instruments to record passing signals.

High Uncertainty and Breakthrough Discovery in Deep Research

Building the IceCube observatory required decades of perseverance through high-risk scientific territory. Kompas.id reported that when Halzen began championing the project four decades ago, it was treated as a highly speculative venture with little guarantee of success. Few conservative, established physicists initially wanted to back the unorthodox proposal.

Despite widespread skepticism, the project pushed forward and yielded results faster than anticipated. Just two years after the gigaton detector reached full operation in 2011, researchers found definitive evidence of cosmic neutrino activity. DetikInet added that planners are already designing an expanded phase for IceCube that will monitor multiple cubic kilometers of ice, further sharpening humanity’s view of obscured cosmic phenomena.

Frequently Asked Questions About the 2026 Nobel Prize in Physics

What is the financial reward accompanying the 2026 Nobel Prize in Physics?

Antara News reported that Francis Halzen receives a cash prize of 12 million kronor Swedia, roughly equivalent to Rp21.4 billion.

Where is Francis Halzen currently affiliated academically?

Kompas.id noted that Francis Halzen serves as a professor at the University of Wisconsin–Madison in the United States, after completing his master’s and doctoral degrees at KU Leuven in Belgium.

When did IceCube achieve its full size and confirm its first cosmic neutrinos?

DetikInet reported that the observatory reached its full size of 5,160 sensors across 86 cables in 2011, with the research team publishing the first evidence of cosmic neutrino detection in 2013.