Cosmic Microwave Background (CMB) radiation is a remnant from the early universe, providing crucial evidence for the Big Bang theory. Discovered in 1965 by Arno Penzias and Robert Wilson, the CMB is a faint glow of microwave radiation that permeates the universe, originating from a time roughly 380,000 years after the Big Bang when the universe cooled enough for protons and electrons to combine and form hydrogen atoms.

This radiation is remarkably uniform, with slight fluctuations that reveal important information about the universe's structure and composition. By studying the CMB, scientists gain insights into the age, expansion rate, and overall geometry of the universe.

The Planck satellite and other observatories have mapped the CMB with unprecedented precision, contributing to our understanding of dark matter, dark energy, and the conditions that led to the formation of galaxies. CMB research continues to be a cornerstone of cosmology, deepening our comprehension of the universe's origins and evolution.