Italian-Americanphysicist and pioneer of X-ray astronomy. In the 1950s he began to build rocket-borne X-ray telescopes. By this means in 1962 he and B. Rossi discovered Scorpius X-1, the first known cosmic X-ray source. Whether as designer, builder, or director, Giacconi has been associated with most of the major X-ray astronomy missions, including Uhuru, the Einstein Observatory, and the Chandra X-ray Observatory. For this work he was awarded a share of the 2002 Nobel Prize in Physics.
Subjects: Astronomy and Astrophysics.