Recent Results from the Cosmic Background Explorer (COBE)

Abstract

NASA Goddard Space Flight Center developed the Cosmic Background Explorer (COBE) satellite to observe the diffuse microwave and infrared radiation from early universe. It also measured diffuse emission from galactic stars, dust, molecules, atoms, ions, and electrons, as well as thermal emission and reflected sunlight from interplanetary dust and comets. It was launched Nov. 18, 19898 by a Delta rocket and carried three instruments. The Differential Microwave Radiometers (DMR) mapped the anisotropy of the cosmic microwave background radiation (CMBR), found a total anisotropy of 11 parts per million on a 10° angular scale, and showed that its angular distribution agrees with scale-invariant primordial fluctuations. The Far Infrared Absolute Spectrophotometer (FIRAS) compared the CMBR with a precise blackbody and showed that the deviations are less than 0.03%. The Diffuse Infrared Background Experiment (DIRBE) mapped the sky at 10 infrared wavelengths and at a wide range of angles from the Sun to enable determination of an extragalactic Cosmic Infrared Background radiation (CIB).