China's large neutrino observatory nears completion

Wang said that the birth of neutrinos is often related to extreme events in the universe, such as the Big Bang, supernova explosions, neutron star mergers, and black hole eruptions, with high-energy neutrinos mainly originating from collisions between cosmic rays and dust or gas.

Although neutrinos have existed since the early universe, it wasn't until 1930 that scientists proposed the hypothesis of their existence. It took another 26 years until physicists experimented with a nuclear reactor and detected the presence of neutrinos.

The mass of neutrinos remains a mystery to this day. Whether they are massless or have mass that directly impacts the evolution laws of the universe, scientists said.

"This construction of the new observatory will bring about significant breakthroughs in neutrino research," Wang said.

The 35.4-meter acrylic sphere is the crucial component of the core equipment of the Jiangmen Underground Neutrino Observatory — the central detector, surrounded by a stainless steel structure and filled with 20,000 tons of liquid scintillator.