China completes core construction of underground neutrino detector

At the heart of the facility is a 35.4-meter acrylic sphere, the world's largest transparent spherical detector designed to capture elusive neutrinos — subatomic particles that play a fundamental role in the universe's structure and evolution. Standing 12 stories tall, the detector represents a major engineering breakthrough in neutrino research.

JUNO is expected to begin operations in August 2025 and will run for at least 30 years. It aims to measure the neutrino mass hierarchy and oscillation parameters, critical to understanding supernova explosion mechanisms, the origins and evolution of the universe, and potentially discovering new physical phenomena.