Space-based Infrared System (SBIRS)

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The Space-based Infrared System (SBIRS) is a constellation of integrated satellites in geosynchronous orbit (GEO) and high elliptical orbit (HEO) and ground-based data processing and command and control centers. This system is designed to provide early missile warning, cue missile defenses, deliver technical intelligence (TECHINT), and support battlespace awareness.1


This system is intended to replace the aging DSP constellation. SBIRS satellites are able to scan large swaths of territory to detect missile activity and can also hone in on areas of interest for smaller-scale activities, including tactical ballistic missile launches. These sensors are independently tasked, meaning the satellite can both scan a wide territory and fixate on a particular area of concern simultaneously. The first satellite, SBIRS GEO-1, launched in May 2011.2

SBIRS is positioned to be the first U.S. asset to detect a ballistic missile launch. Once it detects significant activity, that information is transmitted to Air Force Space Command in Colorado and subsequently to North American Aerospace Defense Command (NORAD) and other relevant agencies who will determine a response, if necessary.3

SBIRS Specifications

The SBIRS constellation has a continuous view of all of the earth’s surface, which it images every 10 seconds while searching for infrared (IR) activity indicating heat signatures.4

SBIRS is able to detect missile launches faster than any other system and can identify the missile’s type, burnout velocity, trajectory, and likely point of impact.5

The system was initially designed to include satellites in low earth orbit (LEO) in what would have been called SBIRS-Low. However, this program was incorporated into the STSS program in 2001 and handed over to the Missile Defense Agency (MDA).6 The current plan for SBIRS was initially dubbed SBIRS-High.

SBIRS GEO was deployed in 2011 and consists of both taskable and nontaskable sensors with both scanning and staring payloads with short- and mid-wave infrared radars. It is able to both have a hemispheric ground of view as well as see very close to the ground and features a more rapid revisit rate than DSP, its predecessor. The GEO sensor payload weighs 1,100 lb. and each satellite reportedly has a pointing accuracy of 0.05 degrees due to three-axis stabilization and a design life of 12 years or more.7

SBIRS HEO, launched in 2006, was the first deployed asset. It is re-taskable and includes a scanning sensor composed of short- and mid-wave infrared radars that can see close to the ground. The GEO sensor weighs 530 lb. The system also integrates with legacy DSP satellites still in orbit. This “system of systems” will be able to detect ballistic missile launches across the globe near instantaneously and be able to notify other U.S. assets, including aegis ships.8


SBIRS began development in 1996 and reached initial operating capacity in 2013. The long procurement period has been attributed to the need to develop infrared sensors with “three times the sensitivity of those in the legacy constellation, and twice the ‘revisit’ rate… [that are able to] operate in multiple infrared wavelengths, enabling them to detect and characterize a wider range of infrared phenomena.”9

SatelliteLaunch Date
SBIRS HEO-1June 2006
SBIRS HEO-2March 2008
SBIRS GEO-1May 2011
SBIRS GEO-2March 2013
SBIRS GEO-3January 2017
SBIRS GEO-4January 2018
SBIRS GEO-5May 2021
SBIRS GEO-6Expected 2022

In addition to the dedicated satellites in GEO, the system also includes two missile warning sensors hosted on classified satellites in HEO that were reportedly launched in June 2006 and March 2008.10

The SBIRS program has faced massive cost overruns and delays. In October 1996, its research and development cost was estimated to be $4.4B for five satellites; this eventually increased to $18.3B for six satellites in 2012.11

Service History

Although SBIRS was designed primarily for missile defense purposes, its short- and mid-wave IR sensors can detect any significant infrared event on the globe, including explosions, fires, and plane crashes. SBIRS provides satellite IR data on thousands of non-missile related events every year. The National Air and Space Intelligence Center keeps “a catalog of signatures—electromagnetic and IR—of aircraft, missiles and other military hardware operating globally.” This can be used to understand what’s going on in crowded operational theaters where there are many actors at play.12

In January 2020, SBIRS detected over a dozen Iranian missile launches targeting U.S. personnel in Iraq. The U.S. Space Force revealed SBIRS’ role in detecting these launches in September 2020.13

Furthermore, TECHINT provided by SBIRS is likely to have helped the U.S. intelligence community piece together the events surrounding the shooting down of Malaysia Airlines Flight 17 (MH17) by a Russian-made BUK missile on July 17, 2014. “[SBIRS] can filter out information about a specific event. The shootdown of an airliner would produce a hot explosion, and operators could likely use the system’s infrared data to forensically image the plume of the offending missile and, perhaps, an approximate location of its launch point. The data could then be correlated against other sources of intelligence to suggest who commanded that particular missile.”14

The system’s non-missile detection role has increased exponentially since its launch. The U.S. Air Force detected and tracked 8,000 IR events in all of 2014 and had already detected over 7,000 between January and August 2015. This increased role will be supported by the creation of a Joint Overhead Persistent Infrared Battlespace Awareness Cell expected to be operational by mid-2016.15

The Next-Generation Overhead Persistent Infrared (“Next Gen OPIR”) constellation in development is planned to supplement and eventually replace SBIRS.16 The USAF initiated the program in 2018, and the first satellite is scheduled to launch in 2025.17


    1. “Space Based Infrared System,” U.S. Air Force, November 23, 2015,
    2. “Space Based Infrared System” U.S. Air Force, November 23, 2015,
    3. Loren Thompson, “SBIRS: The Pentagon’s Most Important Space Program For Preventing Nuclear War,” Forbes, June 8, 2015,
    4. Amy Butler, “An Unprecedented Peek Behind the Sbirs Veil, ” Aviation Week & Space Technology, October 20, 2015,
    5. Amy Butler, “An Unprecedented Peek Behind the Sbirs Veil,” Aviation Week & Space Technology, October 20, 2015,
    6. Marcia S. Smith, Military Space Programs: Issues Concerning DOD’s SBIRS and STSS Programs (CRS Report No. RS21148), (Washington, DC: Congressional Research Service, January 30, 2006),
    7. “Infrared Satellites,” Los Angeles Air Force Base, November 21, 2012,
    8. Amy Butler, “An Unprecedented Peek Behind the Sbirs Veil,” Aviation Week & Space Technology, October 20, 2015,
    9. Loren Thompson, “SBIRS: The Pentagon’s Most Important Space Program For Preventing Nuclear War,” Forbes, June 8, 2015,
    10. “Trumpet 4, 5 / SBIRS HEO-1, 2” Gunter’s Space Page (blog), last updated April 11, 2020,
    11. Paul Dykewicz, “SBIRS Becomes High-cost Priority Amid Cuts,” Space News, May 31, 2021,
    12. Amy Butler, “An Unprecedented Peek Behind the Sbirs Veil,” Aviation Week & Space Technology, October 20, 2015,
    13. Nathan Strout, “US Space Force confirms Space Based Infrared System detected missile attack in January,” C4ISRNet, September 15, 2020,; Nathan Strout, “Exclusive: How the Space Force foiled an Iranian missile attack with a critical early warning,” C4ISRNet, January 7, 2021,
    14. Amy Butler, “An Unprecedented Peek Behind the Sbirs Veil,” Aviation Week & Space Technology, October 20, 2015,
    15. Amy Butler, “An Unprecedented Peek Behind the Sbirs Veil,” Aviation Week & Space Technology, October 20, 2015,
    16. Brian Everstine, “Lockheed Receives Up to $4.9 Billion for Next-Gen OPIR Satellites,” Airforce Magazine, January 5, 2021,
    17. Sandra Erwin, “GAO flags concerns about procurement of DoD’s early warning satellites,” Space News, June 3, 2020,
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Missile Defense Project, "Space-based Infrared System (SBIRS)," Missile Threat, Center for Strategic and International Studies, August 11, 2016, last modified July 26, 2021,