[Doc Ewen looks into the horn antenna, 1950]
Image courtesy of Doc Ewen


Harvard Cyclotron: 1948-1951

Detection of HI Line: 1951

Harvard 24ft and 60ft and NRAO founding: 1952-1956

1950s and 1960s: Two Roads that Crossed

Microwave & Millimeter Wave Applications in the 1970s and 1980s

Mm Wave Radiometry in the 1990s

May 2001 visit to NRAO Green Bank



[Doc Ewen and horn antenna, 2001]
Image courtesy of Doc Ewen

Doc Ewen: The Horn, HI, and Other Events in US Radio Astronomy

by Doc Ewen, © 2003

Slide 31: Detecting the Interstellar Hydrogen Line, 1951

[Letter from Pawsey to Purcell]

Letter from Pawsey to Purcell, May 18, 1951. Pawsey appreciates the description of technique, and notes that their first observations will be "tonight". He agrees with Purcell about sending a short note to Nature, and appreciates the confirmation opportunity. He mentions the large number of radio astronomy papers that have appeared in the Australian Journal of Scientific Research, Series A (Physical Sciences) and suggests that journal as a possible place for a longer paper on the detection. He sends congratulations to Ewen. [Photo courtesy of Doc Ewen]

Slide 32
Modified on Monday, 06-Sep-2004 14:16:35 EDT by Ellen Bouton