Solar neutrino

A solar neutrino is a neutrino originating from nuclear fusion in the Sun's core, and is the most common type of neutrino passing through any source observed on Earth at any particular moment.^{[citation needed]} Neutrinos are elementary particles with extremely small rest mass and a neutral electric charge. They only interact with matter via weak interaction and gravity, making their detection very difficult. This has led to the now-resolved solar neutrino problem. Much is now known about solar neutrinos, but research in this field is ongoing.