GCASO: General Catalog of Artificial Space Objects

Jonathan C. McDowell

Launch Sites

Rocket Launch Ships: US Missile Test Launch Vessels

USNS Observation Island


US Navy


The Empire State Mariner was built in 1953 for United States Lines and the US Maritime Commission. It was transferred to the USN in 1956 and redesignated EAG-154 (Experimental Miscellaneous Auxiliary) Observation Island. It was redesignated AG-154 in Apr 1968, placed in reserve 1972-79 and then used by Military Sealift Command as the missile range instrumentation ship USNS Observation Island, designated T-AGM-23. It was retired in 2014.


Rockets used: Polaris AX,Polaris A1,Polaris A2,Polaris A3,Poseidon C3



Updated: 2021 Sep 24 01:17:06

Launches: EAG-154
DateRocketFlightMissionPlatCodePlatformSiteLPAscSiteAscLPPosApogee
1959 Aug 27 1652Polaris AX--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 500.0
1960 Mar 29Polaris A1Integrated test-EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 300.0
1960 Apr 18Polaris A1--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 50.0
1960 May 23Polaris A1--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 500.0
1960 Jun 23 0222Polaris A1--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 500.0
1960 Jul 7Polaris A1--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 0.0
1961 Mar 1 1819Polaris A2--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 1000.0
1961 Mar 9Polaris A2--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 1000.0
1961 May 25 1953Polaris A2--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 0.0
1961 Jun 26 1842Polaris A2--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 500.0
1961 Aug 18Polaris A2--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 2.0
1961 Oct 4 1422Polaris A2(A2X-15?)-EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 1000.0
1962 Sep 14 0809:06Polaris A1--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 500.0
1962 Sep 15 2037:10Polaris A1--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 500.0
1962 Oct 14Polaris A1--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 500.0
1962 Oct 14Polaris A1--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 10.0
1963 Apr 10 2033:07Polaris A3--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 1.0
1963 Apr 26 1831:23Polaris A3--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 80.0
1963 Jun 17 1614:02Polaris A3--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 1000.0
1963 Jun 21 1544:03Polaris A3--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 1000.0
1963 Sep 27 0325:00Polaris A3Steam eject, PX-2-EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 1000.0
1963 Oct 4 0518:07Polaris A3PX-2-EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 1000.0
1963 Nov 27 0610:59Polaris A3PX-2,PY-2-EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 40.0
1963 Dec 11 0100:06Polaris A3PX-2,PY-2-EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 10.0
1964 Jan 20 1702:01Polaris A3--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 1000.0
1964 Apr 1Polaris A3PX-2-EAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 1000.0
1964 Apr 8Polaris A3PX-2-EAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 10.0
1964 May 12Polaris A3PY-2-EAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 1000.0
1964 Nov 20Polaris A3PX-2-EAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 1000.0
1964 Nov 25Polaris A3PX-2-EAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 1000.0
1965 Sep 22Polaris A3PX-2-EAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 1000.0
1967Polaris A1ISEP 1Mk 2 RVEAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 500.0
1967Polaris A1ISEP 2Mk 2 RVEAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 500.0
1967Polaris A1ISEP 3Mk 2 RVEAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 500.0
1967 May 17Polaris A3USN Mk 2 Mod 2 RV x 2-EAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 500.0
1967 Jun 21Polaris A3Antelope 5-EAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 500.0
1967 Jun 21Polaris A3Antelope 6-EAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 500.0
1967 Nov 29Polaris A3USN Mk 2 Mod 2 RV x 2-EAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 500.0
1967 Dec 6Polaris A3Antelope 10-EAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 500.0
1968Polaris A1ISEP 6Mk 2 RVEAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 500.0
1968 Mar 16Polaris A3USN Mk 2 Mod 2 RV x 2Mk 2 Mod 2 RVs+DecoysEAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 500.0
1968 Apr 4Polaris A3USN Mk 2 Mod 2 RV x 2-EAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 500.0
1968 Apr 11Polaris A3USN Mk 2 Mod 2 RV x 2-EAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 500.0
1968 Apr 19Polaris A3USN Mk 2 Mod 2 RV x 2-EAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 500.0
1968 May?Polaris A1ISEP 4Mk 2 RVEAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 500.0
1968 May?Polaris A1ISEP 5Mk 2 RVEAG-154USNS Observation IslandJILP2-- 169.5W 16.7N (+/- 0.0) 100.0
1969 Dec 16 1725Poseidon C3--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 500.0
1970 Feb 4 2038Poseidon C3--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 100.0
1970 Mar 24 1917Poseidon C3--EAG-154USNS Observation IslandETRSLBM-- 79.0W 28.5N (+/- 2.0) 500.0
1971 Apr 15Polaris A2Safeguard M1-7-EAG-154USNS Observation IslandMIDLP4-- 177.5W 24.8N (+/- 0.2) 1000.0
1971 May 7Polaris A2Safeguard M1-8-EAG-154USNS Observation IslandMIDLP4-- 177.5W 24.8N (+/- 0.2) 1000.0
1971 Nov 10Polaris A2Safeguard M2-5-EAG-154USNS Observation IslandMIDLP4-- 177.5W 24.8N (+/- 0.2) 1000.0
1971 Nov 12Polaris A2Safeguard M2-8-EAG-154USNS Observation IslandMIDLP4-- 177.5W 24.8N (+/- 0.2) 1000.0
1971 Dec 8Polaris A3Safeguard M2-3-EAG-154USNS Observation IslandMIDLP4-- 177.5W 24.8N (+/- 0.2) 1000.0