[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

Proposed materials for the Introduction page

The War years of the 1940s accelerated the pace of technology enhancements for many applications with common denominator hardware needs. Electronics and computer technology were exploding with new capabilities. The MIT Radiation Laboratory provided a demonstrated capability of how to accelerate the growth of technology. The tools to move quickly ahead were in hand. The Rad Lab example spawned Lincoln Laboratory, MITRE, The Aerospace Corporation, and Jet Propulsion Laboratory as semi-government Labs with close ties to academic centers. The transistor arrived in 1951 and the technological revolution was in full swing. In the late 1940s all of the technology ingredients needed to launch an aggressive national radio astronomy effort were in place. In the early 1950s, [detection of] the hydrogen line provided the temporary focus needed to ignite an integrated effort with a common goal. The leadership of the National Radio Astronomy Observatory during the 1950s, 1960s and 1970s was the critical factor that maintained the momentum and guaranteed the promise of a Center of Excellence.

Common denominator hardware interests led to several joint efforts with Department of Defense and NASA to meet the needs of individual applications. Some were planned, but most were the simple recognition of the common denominator hardware capabilities needed for diverse applications. This is covered in greater detail in Two Roads (installment four of this narrative).

During the 1950s the focus was on microwaves, 1-10 GHz, and large single parabolic antenna reflectors up to 210 feet in diameter. With the arrival of the space age, the NASA/DoD interest in large single parabolic antennas continued, but now it was driven by the requirements of the Deep Space Communication Network needed to support activities in near earth orbit as well as in the solar system. With the Space Age came the need for low noise receivers as well as high power transmitters. The combination of large antennas and low noise receivers is the recipe for radio telescopes. The availability of high power transmitters filled the needs of radar astronomers. Throughout the 1950s and 1960s it was a win-win situation for radio astronomy.

Modified on Monday, 18-Jul-2005 11:42:50 EDT by Ellen Bouton