Doc Ewen

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

by Doc Ewen, © 2003


Slide 22: Detecting the Interstellar Hydrogen Line, 1951

[Gas discharge noise source]

The throat of the horn antenna enters at the right. The gas discharge noise source in the foreground is hung by a rope from the ceiling. [Photo courtesy of Doc Ewen]

Slide 23
Modified on by Ellen Bouton