Herbert S. Bridge PhD '50
Professor Emeritus of Physics Herbert S. Bridge PhD '50, an internationally known space scientist who played a key role in mapping the solar winds that flow through interplanetary space, died Aug. 30 following a long illness. Bridge, 76, died from coronary artery disease.
Bridge was director of the Center for Space Research and a pioneer in the exploration of the solar system from unmanned spacecraft. He led a group of MIT physicists in creating a novel instrument for the study of interplanetary plasma, the modulated-grid Faraday cup.
This instrument, successfully flown aboard Explorer X in 1961, provided for the first time direct evidence of the existence of dilute plasma in interplanetary space, as well as supplying some preliminary information on the density and velocity of this plasma.
After that discovery, Bridge became the principal investigator on space plasma experiments that flew aboard unmanned missions to every planet in the solar system except Pluto. The work by Bridge and his collaborators received worldwide recognition, and the MIT group acquired a leading position in the field of plasma measurements in outer space.