 Launch of USA-273 on anAtlas V | |
| Names | SBIRS GEO-3 (SV-4) Space-Based Infrared System GEOstationary-3[1] |
|---|---|
| Mission type | Infraredearly warning IRINT |
| Operator | United States Air Force /United States Space Force |
| COSPAR ID | 2017-004A |
| SATCATno. | 41937 |
| Website | https://www.spaceforce.mil/ |
| Mission duration | 12 years (planned) 9 years and 26 days(in progress) |
| Spacecraft properties | |
| Spacecraft | SBIRS GEO-3 |
| Spacecraft type | SBIRS GEO |
| Bus | A2100M |
| Manufacturer | Lockheed Martin Space |
| Launch mass | 4,500 kg (9,900 lb) |
| Dimensions | 15 m x 6.7 m x 6.1 m |
| Start of mission | |
| Launch date | 21 January 2017, 00:42UTC[2] |
| Rocket | Atlas V 401 (AV-066) |
| Launch site | Cape Canaveral,SLC-41 |
| Contractor | United Launch Alliance |
| Orbital parameters | |
| Reference system | Geocentric orbit |
| Regime | Geostationary orbit |
| Instruments | |
| 2 SBIRS sensors | |
USA-273, also known asSBIRS GEO-3,[1] is aUnited Statesmilitary satellite and part of theSpace-Based Infrared System (SBIRS).
The SBIRS satellites are a replacement for theDefense Support Program (DSP) early warning system. They are intended to detectballistic missile launches, as well as various other events in theinfrared spectrum, includingnuclear explosions,aircraft flights, space objectentries and reentries,wildfires, andspacecraft launches.
The mission of SBIRS states that "The SBIRS program was designed to provide a seamless operational transition from DSP to SBIRS and meet jointly-defined requirements of the defense and intelligence communities in support of the missile early warning, missile defense, battlespace awareness and technical intelligence mission areas."[3]
SBIRS-GEO 3 was manufactured byLockheed Martin Space and was built upon theA2100M, a militarized, radiation hardenedsatellite bus that provides power, attitude control, command and control, and a communications subsystem with five separate mission data downlinks to meet mission requirements, including system survivability and endurability requirements.[3]
TheSBIRSsensors are designed to provide greater flexibility and sensitivity than the DSPinfrared sensor, in addition to detecting short-wave and mid-wave infrared signals, allowingSBIRS to perform a broader set of missions. These enhanced capabilities result in improved prediction accuracy for global strategic and tactical warfighters. Improvements to the ground system processing software are on-going, resulting in increased event message accuracy and reduced manpower requirements for support and operations of the DSP and SBIRS.[3]
The infraredpayload consists of two sensors; a scanner and a step-starer. The scanning sensor continuously scans the Earth to provide 24/7 global strategic missile warning capability. Data from the scanner also contributes to theater and intelligence missions. The step-staring sensor provides coverage for theater missions and intelligence areas of interest. On-board signal processing allows detected events to be transmitted to the ground, but the raw, unprocessed data gathered by the infrared sensors are down-linked as well, so the sameradiometric scene observed in space will be available for ground-based processing.[3]
USA-273 was launched on 21 January 2017 fromCape Canaveral (CCAFS) atop anAtlas V 401launch vehicle.
This article incorporates text from this source, which is in thepublic domain.