Rossi, Bruno Benedetto (1905–1993)
Italian-American physicist who was a pioneer in the study of cosmic
rays. In the 1930s, his experimental investigations of cosmic rays and
their interactions with matter laid the foundation for high energy particle
physics. Cosmic rays consist of a variety of charged particles, mainly protons
and alpha particles, that enter Earth's atmosphere from space at speeds
approaching that of light, bombarding atmospheric atoms to produce mesons
as well as secondary particles possessing some of the original energy. Rossi
was one of the first to use rockets to study cosmic rays above the atmosphere.
Finding X-rays from space he became the father of high energy astrophysics,
being largely responsible for starting X-ray astronomy, as well as the study
of interplanetary plasma.
Rossi and his colleagues discovered the first non-solar source of X-rays
– Scorpius X-1. In 1996, NASA
renamed its X-ray Timing Explorer (XTE) space telescope to honor him (see
Rossi served as professor of Physics and Professor Emeritus at MIT, and
in 1987 was the co-recipient of the prestigious Wolf Prize in Physics. The
Bruno B. Rossi Prize, awarded annually to a top astrophysicist for achievements
in the field, is named in his honor.