Geosynchronous Space Situational Awareness Program

Geosynchronous Space Situational Awareness Program (GSSAP) or Hornet is a class of United States spy satellites.

Delta IV 368 launches GSSAP 1 and 2 from Cape Canaveral Air Force Station on 2014

GSSAP artist rendering

The first two GSSAP spacecraft , GSSAP 1 (USA-253) and GSSAP 2 (USA-254) were launched in 2014. They were built by Orbital Sciences Corporation; their capabilities and development and construction budgets are classified. They operate in "near-geosynchronous orbit",^[1][2] The first launch was scheduled for 23 July 2014 aboard a United Launch Alliance Delta IV launch vehicle.^[3] Even during the testing process these satellites were pressed into early service to fulfill critical needs.^[4] In August 2023 the Space Systems Command announced the retirement of the GSSAP-2 satellite, the first of the constellation to be decommissioned, and its subsequent transfer into a graveyard orbit.

Liftoff of GSSAP 3 and 4 on 19 August 2016 atop Delta IV 375 from Cape Canaveral Air Force Station

GSSAP 3 (USA-270) and 4 (USA-271) satellites were launched on 19 August 2016. On 12 September 2017, both were declared operational.^[5] USA-270 approached two Chinese satellites in GEO to examine them more closely.^[6] In 2023, Chinese researchers reported having observed 13 other instances where US satellites approached Chinese ones.^[7]

Atlas V AV-084 lifts off from Cape Canaveral Space Force Station, Florida, 21 January 2022 with GSSAP-5 and GSSAP-6.

Two more satellites (GSSAP-5 and GSSAP-6) have been successfully launched on 21 January 2022 by a Atlas V launch vehicle.^[8]

In August 2023 the Space Systems Command revealed that two more satellites have been ordered to Northrop Grumman to keep up with the demand for GSSAP assets.^[9] The launches of the new satellites were planned for 2024 and 2027 respectively, with the spacecraft being the first of the constellation not to be launched in pairs.^[10]

GSSAP 7 and 8 are scheduled to be launched together in 2025 by a Vulcan Centaur VC4S.^[11][12][13] GSSAP 9 and 10 will follow in 2027.^[11]

Satellites

Name	NSSDC ID	Launch date	Launcher
GSSAP 1, Hornet 1, USA 253	2022-174A	23 July 2014 23:28	Delta IV 368
GSSAP 2, Hornet 2, USA 254	2022-174B
GSSAP 3, Hornet 3, USA 270	2016-052A	19 August 2016 04:52	Delta IV 375
GSSAP 4, Hornet 4, USA 271	2016-052A
GSSAP 5, Hornet 5, USA 324	2022-006A	21 January 2022 19:00	Atlas V AV-084
GSSAP 6, Hornet 6, USA 325	2022-006B
GSSAP 7, Hornet 7, USSF 87		2025	Vulcan Centaur VC4S
GSSAP 8, Hornet 8, USSF 87
GSSAP 9, Hornet 9		2027
GSSAP 10, Hornet 10