The Cosmic Background Explorer (COBE) was used to make detailed microwave maps of the universe. COBE was launched on November 18, 1989, and had three scientific instruments on board: the Far Infrared Absolute Spectrophotometer (FIRAS), the Differential Microwave Radiometer (DMR), and the Diffuse Infrared Background Explorer (DIRBE). Data gathered by COBE confirmed the presence of the cosmic microwave background that was evidence of the Big Bang. COBE measured the temperature of the background to be 2.7 degrees Kelvin (almost absolute zero) and also showed that the imperfections in the background indicated the origins of structure in the universe.