Mather, John Cromwell (1946-…), an American physicist, won a share of the 2006 Nobel Prize in physics for his research on the heat left over from the early universe. Scientists call this heat the cosmic microwave background (CMB) radiation. Mather shared the prize with the American physicist George F. Smoot III, who also studied the CMB radiation. Mather and Smoot’s work forms part of a branch of physics and astronomy called cosmology, the study of the universe and its origin.
Mather’s work helped confirm the big bang theory. According to the theory, the universe began in a cosmic explosion called the big bang that occurred about 14 billion years ago. The CMB radiation formed about 400,000 years later. At the time, the universe still existed in an extremely hot, dense state. Hot objects radiate energy with a range of wavelengths, called a spectrum. For some hot objects, the amount of energy radiated at a given wavelength depends only on the object’s temperature. Scientists call such an object a black body and describe the radiation it gives off as a black-body spectrum. Cosmologists theorized that if the CMB radiation was actually heat remaining from shortly after the big bang, it should exhibit a black-body spectrum.
Mather led a team of researchers that studied data collected by the Cosmic Background Explorer (COBE) satellite, launched in 1989. The COBE satellite included an instrument called a spectrometer that measured the spectrum of the CMB radiation. In 1990, Mather and his team reported that the CMB radiation had a black-body spectrum, a conclusion that supported the big bang theory.
Mather was born on Aug. 7, 1946, in Roanoke, Virginia. He received his doctorate degree in physics from the University of California at Berkeley in 1974. Mather conducted research at the National Aeronautics and Space Administration (NASA) Goddard Institute for Space Studies at Columbia University in New York City from 1974 to 1976. In 1976, he began working as an astrophysicist at the NASA Goddard Space Flight Center in Greenbelt, Maryland.
Since 1995, Mather has led the team of scientists who developed the James Webb Space Telescope. The telescope is the most powerful observatory ever built. It collects information on the first stars and galaxies that formed after the big bang, on the formation of planetary systems, and on the evolution of planets within our solar system.
