The cosmic microwave background (CMB) radiation was measured using instruments that conducted full-sky surveys rather than focusing on a single point like the Hubble Space Telescope. These measurements involved capturing data from all directions in the sky to create a comprehensive map of the CMB. Various missions, such as COBE, WMAP, and Planck, contributed to our understanding of the CMB's uniformity and fluctuations. The data collected has been crucial for cosmology, providing insights into the early universe and the formation of large-scale structures. Understanding the CMB continues to be essential for studying the universe's evolution and fundamental physics.
