🛰️ SATELLITE · HISTORICAL RECORD
HS-301 Syncom C
Retired 1974HS-301 Syncom C (NORAD 858, COSPAR 1964-047A) is a retired US satellite, withdrawn from service around 29 Dec 1974, launched on 19 Aug 1964 on the Syncom C mission. It was operated by GSFC as part of the Syncom programme. The spacecraft was built by HSES on the HS-301 bus, with a mass of 34 kg. Historical record from Orbital Radar's satellite archive, cross-referenced with the live satellite catalogue.
1964
launched
1974
retired
62
years on orbit
34
kg mass
Lifecycle
Launched19 Aug 1964 · on the Syncom C mission
Operational29 Dec 1974 · entered service
Retired29 Dec 1974 · end of operational service
StatusOn orbit (not live-tracked)
Specifications
NORAD ID858
COSPAR1964-047A
TypeSatellite
OperatorGSFC
Country / StateUS
ManufacturerHSES
BusHS-301
Mass34 kg (33 kg dry)
ProgrammeSyncom
CategoryCOM
OrbitGEO (GEO/S)
Altitude35,640 × 35,926 km
Inclination1.0°
Frequently asked questions
What happened to HS-301 Syncom C?
HS-301 Syncom C was retired from service around 29 Dec 1974 after launching in 1964. It is no longer operational but remains catalogued.
Who operated and built HS-301 Syncom C?
HS-301 Syncom C was operated by GSFC and built by HSES (US).
Historical record from the Orbital Radar satellite archive. Sources & methodology: data sources. Accessed 2026-09-06.