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Secor II S/N 18 (ITT MAT)

Retired 1975

Secor II S/N 18 (ITT MAT) (NORAD 4363, COSPAR 1970-025B) is a retired US satellite, withdrawn from service around 1 Jan 1975, launched on 8 Apr 1970 on the Nimbus D mission. It was operated by ARTOPL as part of the Secor II programme. The spacecraft was built by ITT on the Secor bus, with a mass of 18 kg. Historical record from Orbital Radar's satellite archive, cross-referenced with the live satellite catalogue.

1970
launched
1975
retired
56
years on orbit
18
kg mass

Lifecycle

Launched8 Apr 1970 · on the Nimbus D mission
Operational1 Jan 1975 · entered service
Retired1 Jan 1975 · end of operational service
StatusOn orbit (not live-tracked)

Specifications

NORAD ID4363
COSPAR1970-025B
TypeSatellite
OperatorARTOPL
Country / StateUS
ManufacturerITT
BusSecor
Mass18 kg
ProgrammeSecor II
CategoryGEOD
OrbitLEO (LEO/S)
Altitude1,085 × 1,090 km
Inclination99.9°

Frequently asked questions

What happened to Secor II S/N 18 (ITT MAT)?

Secor II S/N 18 (ITT MAT) was retired from service around 1 Jan 1975 after launching in 1970. It is no longer operational but remains catalogued.

Who operated and built Secor II S/N 18 (ITT MAT)?

Secor II S/N 18 (ITT MAT) was operated by ARTOPL and built by ITT (US).

Launched together

Nimbus DNORAD 4362
Historical record from the Orbital Radar satellite archive. Sources & methodology: data sources. Accessed 2026-09-06.