muon

A muon is a fundamental particle similar to an electron but with greater mass, roughly 200 times larger. It belongs to the family of particles called leptons and is produced naturally when cosmic rays from space collide with atoms in Earth's atmosphere. Muons are unstable and decay quickly—within microseconds—transforming into other particles. Because they're abundant in cosmic ray interactions, muons help scientists study particle physics and atmospheric processes. Despite their short lifespan, muons can travel deep into the Earth, enabling their use in applications like imaging and research into fundamental particles.