Italian-Americanphysicist. In 1931 he showed that some cosmic rays have very high energies. After working in particle physics, Rossi seized the opportunities provided by the space age. He showed in 1958 that the interplanetary medium contains ionized gas. In 1961 he mapped the Earth's magnetopause, and in 1962, with R. Giacconi, he discovered the X-ray source Scorpius X-1. The Rossi X-ray Timing Explorer was named in his honour.
Subjects: Astronomy and Astrophysics.