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

Slide 31: Detecting the Interstellar Hydrogen Line, 1951

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]
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