Wilkinson Microwave Anisotropy Probe (WMAP)

The Wilkinson Microwave Anisotropy Probe (WMAP) is a spacecraft launched in 2001 to study the universe's early moments. It measured faint microwave signals coming from all directions, revealing tiny temperature differences in the cosmic microwave background radiation—echoes of the universe’s birth about 13.8 billion years ago. These measurements help scientists understand the universe's composition, age, and development, including the proportions of dark matter, dark energy, and ordinary matter. WMAP’s detailed data provided a precise map of the universe’s initial conditions, significantly advancing our knowledge of cosmic history and structure formation.