Every second, our bodies encounter elusive particles that a subterranean sphere must capture (video).

Chinese physicists are finalizing the construction of the Jiangmen Underground Neutrino Observatory, or JUNO, which will detect so-called ghost particles, or neutrinos. These are extremely light subatomic particles with no electric charge. Physicists aim to determine which of the three types of neutrinos is the heaviest, as reported by Popular Mechanics.

Every second, trillions of neutrinos pass through our bodies. These particles can be produced by stars as well as through processes of nuclear decay on Earth. It is known that the three types of neutrinos can transform from one type to another. Accurately identifying which of these neutrino types is the heaviest will provide insights into the processes that occurred in the very first hours and days after the Big Bang. This will also help to understand why all the matter that makes up the Universe is as it is.

Neutrinos are often referred to as ghost particles because they are extremely difficult to detect. The goal of the new Jiangmen Underground Neutrino Observatory or JUNO is to detect these particles and determine their properties. The neutrino detector has been specially built underground to minimize background noise that occurs during the search for these elusive particles.

At the center of the detector, located 700 meters underground, is an acrylic sphere approximately 35 meters in diameter. It will be filled with 20,000 tons of water. Chinese physicists claim that this is the largest neutrino detector of its kind in the world. The sphere is covered with sensors that will be able to detect any disturbances in the liquid inside, as these movements contain evidence of neutrino passage.

Chinese physicists will analyze data on neutrinos produced by the two nearest nuclear power plants as a byproduct of nuclear decay. The new detector will also be able to observe neutrinos emanating from the Sun, as well as those generated by the radioactive decay of uranium and thorium in the Earth's interior.

The JUNO neutrino observatory is expected to begin operations later this year, as its construction is nearly complete.

About 100 years ago, physicists first predicted the existence of neutrinos, which are products of nuclear reactions throughout the Universe. This means that nuclear power plants produce neutrinos just like the Sun and other stars do.