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

Introduction

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

Bibliography

Permissions


[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


Millimeter Wave Radiometry in the 1990s: MAPS slide 9

[MAPS images]

The last set of MAPS images obtained in South Deerfield, early spring 2003. Left to right: 35 GHz, 60 GHz, 95 GHz. This image set is a treasure of passive millimeter wave phenomenology. Note particularly:
  • The difference in spatial resolution at 35 and 95 GHz
  • The cold sky noise at 35 and 95 GHz compared with the warm sky at 60 GHz
  • The "shadow" of the tree at 60 GHz caused by the cold ground in the shadow
  • The underground cable seen at 60 GHz, crossing the shadow of the tree
  • The spatial detail of the tree seen at 95 GHz
  • The cold shadow of the storage trailer seen at both 60 and 95 GHz
Credit: Photos courtesy of Doc Ewen.

MAPS slide 10
Modified on Sunday, 05-Jun-2005 08:01:31 EDT by Ellen Bouton