Cosmic Microwave Background Radiation

The Cosmic Microwave Background (CMB) radiation provides the most powerful evidence for the Big Bang theory. Accidentally detected in 1964 by Arno Penzias and Robert Wilson, this faint glow is the afterglow of the universe's birth approximately 13.8 billion years ago. The CMB exhibits a nearly uniform temperature of 2.725 Kelvin across the entire sky, a precision that makes it a unique cosmic relic. Its blackbody spectrum matches theoretical predictions to within 50 parts per million, a degree of accuracy surpassing typical cosmological benchmarks. The discovery of the CMB shifted our understanding from a universe with no clear beginning to one with a definitive origin point and subsequent evolution.