Arno Penzias

Born on 26 April 1933 in Munich, Germany, Arno Penzias is a physicist and Nobel laureate best known for his codiscovery of the cosmic microwave background. In 1939, at the age of 6, Penzias immigrated with his family to the US to escape Nazi persecution for being Jewish. He attended the City College of New York, earning his BA in physics in 1954. After a two-year stint in the US Army Signal Corps, he applied to Columbia University, where he earned his PhD in 1962. Penzias then went to work at Bell Laboratories, where he would remain for the next 37 years. There he focused on radio astronomy and satellite communications. While trying to measure radio signals from the Milky Way using the Holmdel Horn Antenna in the mid 1960s, he and fellow radio astronomer Robert Wilson detected a mysterious, isotropic noise. To identify where it was coming from, they systematically eliminated all possible sources. The signal turned out to be the cosmic microwave background, remnant radiation from the Big Bang. For that discovery the pair were awarded one-half of the 1978 Nobel Prize in Physics. Penzias went on to make further discoveries, write more than 100 scientific papers, and receive more than a dozen patents. In 1977, he and Wilson were also awarded the National Academy of Sciences’ Henry Draper Medal and the Royal Astronomical Society’s Herschel Medal. Since 1997 Penzias has been a venture partner at New Enterprise Associates. (Photo credit: AIP Emilio Segrè Visual Archives, Physics Today Collection)

Date in History: 26 April 1933