1
Space News, Jan. 7, 2002, p. 14.
2
Space & Missile Defense Report, Jan. 18, 2001, p. 8. More recent data could not be obtained
in the open literature.
Congressional Research Service ˜ The Library of Congress
CRS Report for Congress
Received through the CRS Web
Order Code RS21148
Updated January 30, 2006
Military Space Programs: Issues Concerning
DOD’s SBIRS and STSS Programs
Marcia S. Smith
Specialist in Aerospace and Telecommunications Policy
Resources, Science, and Industry Division
Summary
The Department of Defense’s (DOD’s) programs to develop new satellites to alert
U.S. military commanders to foreign missile launches, and to support missile defense
objectives, are controversial because of cost growth and schedule slippage. SBIRS-
High, managed by the Air Force, would replace existing Defense Support Program
“early warning” satellites. The Space Tracking and Surveillance System (STSS,
formerly SBIRS-Low), managed by the Missile Defense Agency, would perform missile
tracking and target discrimination for missile defense objectives. The SBIRS-High
program has breached Nunn-McCurdy cost growth limits several times, resulting in
several program restructurings. This is the final edition of this report.
Satellite Early Warning Systems
The United States began developing early warning satellite systems in the 1950s to
alert the National Command Authority to foreign missile launches. The current series is
called the Defense Support Program (DSP). The first DSP satellite was launched in
November 1970; 22 have been launched to date, most recently in February 2004. The
final DSP was delivered to the Air Force in May 2005 for launch later in the year. Each
DSP can operate for up to 10 years.
1
Four satellites reportedly are needed for a full
operational capability. Six satellites reportedly were operating in January 2001.
2
DSP satellites (built by Northrop Grumman Space Technology, which was formerly
TRW Space and Electronics) use infrared sensors to detect the heat of fuel exhausts
associated with missile launches. Sensors on the satellites also can detect nuclear bursts
associated with the detonation of nuclear weapons. A February 2001 General Accounting
