 Cosmic microwave background experiments

Cosmic Microwave Background (CMB) experiments are scientific investigations designed to study the CMB radiation, which is a faint glow of microwave radiation that fills the universe. This radiation is an important relic from the early universe, specifically from the time approximately 380,000 years after the Big Bang, when protons and electrons combined to form neutral hydrogen atoms, allowing photons to travel freely through space for the first time.