CMB

What is the Cosmic Microwave Background radiation? How do fluctuations in the CMB allow scientists to understand the structure of the Universe? CMB is a faint glow of light that fills the universe, falling on Earth from every direction with nearly uniform intensity. It is the residual heat of creation. The CMB is the oldest light we can see; the farthest back both in time and space that we can look. Its temperature is extremely uniform all over the sky. However, tiny temperature variations or fluctuations can offer great insight into the origin, evolution, and content of the universe. The fluctuations in the CMB allow scientists to understand how old the Universe is based on measurements of the expansion using Type Ia supernovae. By studying these fluctuations, cosmologists can learn about the origin of galaxies and large-scale structures of galaxies. The fluctuation of CMB also helps the scientists to measure the basic parameters of the Big Bang theory. Sources: NASA Scientific American