The Cosmic Background Explorer (COBE): Mission and Science Overview

Abstract

Ever since the discovery in 1964 of the Cosmic Microwave Background (CMB), scientists have tried to make accurate measurements of its spectrum and anisotropie3. With the successful COBE mission, major advances in our understanding of the very early universe have been achieved.COBE’s complement of instruments are the Far Infrared Absolute Spectrophotometer (FIRAS), the Differential Microwave Radiometers (DMR), and the Diffuse Infrared Background Experiment (DIRBE). FIRAS and DIRBE are located inside a 4He dewar to operate at 1.5 K. DMR receivers are located around the outside of the dewar. The instruments and mission plan have been described by Gulkis et al. (1990). Essential for the cosmological objectives are the all-sky observing strategy, periodic absolute calibrations of the instruments, high sensitivity, and extensive care to minimize potential systematic errors.