National Security Archive: Space-Based Early Warning: From MIDAS to DSP to SBIRS


Space-Based Early Warning: From MIDAS to DSP to SBIRS

Cold-War DSP System Is Now in the Process of Transition to SBIRS

First SBIRS GEO Scheduled to Become Operational in January 2013

Defense Support Program Sometimes Served as Cover for Spy Satellite Missions, Documents Show

National Security Archive Electronic Briefing Book No. 235 (UPDATED)
Edited by Jeffrey T. Richelson

Posted – January 8, 2013

UPDATE of November 9, 2007 Posting

For more information contact:
Jeffrey T. Richelson – 202/994-7000

Washington D.C., January 8, 2013 — As the United States prepares to transition this month from Cold War-era missile detection programs to a more sophisticated infrared platform, recently declassified documents published by the National Security Archive take a fresh look at the history of the U.S. space-based early warning program. The new materials flesh out critical details about the progress and problems associated with the new "SBIRS" program, which is about to become operational. Among the records posted for the first time today are internal memos discussing such sensitive topics as the utility of using "white" defense warning programs as cover for classified signals intelligence satellite launches.

This posting updates a November 9, 2007, electronic briefing book published in anticipation of the final Defense Support Program (DSP) spacecraft launch.

Today’s update includes the documents from the original posting plus an additional 17 documents. Largely obtained through the Freedom of Information Act and archival research, they cover the theoretical work behind the concept of space-based missile detection, early doubts about the feasibility of such detection, and 1960s research and development work on the Missile Defense Alarm System (MIDAS). They also include documents on the evolution of the Defense Support Program (DSP) with regard both to its capabilities and its use for a variety of additional missions, including problems with some of the program’s early satellites.

Compiled by National Security Archive Senior Fellow Dr. Jeffrey T. Richelson, the documents in this briefing book originated with the Defense Department, Air Force, U.S. Space Command, U.S. Strategic Command, Air Force Space and Missile Systems Center, Aerospace Corporation, General Accounting Office, and other organizations.

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