[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 18: Detecting the Interstellar Hydrogen Line, 1951

[Doc Ewen looking into the horn antenna]

Inspecting the patch work. After one year, parts of the copper skin had cracked and peeled away from the plywood. I purchased fifty feet of rope from a local hardware store, tied one end around my waist and the other to the lower section of the antenna mount. With a large soldering iron, solder, and a bristle brush I went over the side, four floors up, and slid into the horn. About an hour later, I managed to climb out of the horn back on to the parapet. This picture of me inspecting the patchwork was taken about two days later. The line was detected within the next few weeks. [Photo courtesy of Doc Ewen]

Slide 19
Modified on Monday, 06-Sep-2004 14:28:00 EDT by Ellen Bouton