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// optical imaging · 1973

Cosmos 551

Cosmos 551 was launched on March 6, 1973 aboard a Voskhod 11A57 from Baikonur. Latest status in GCAT: landed (Mar 20, 1973).

COSPAR 1973-012ANORAD 6378Soviet Union

Identity

Name in GCAT
Kosmos-551
Common name
Cosmos 551
Payload designation
Rotor No. 39L
Other names
Zenit-4M No. 39L:P,11F691 No. 770-24-23-249:RA
International designator
1973-012A
NORAD catalog number
6378
GCAT identifier
S06378
UN registration
A/AC.105/INF.271

Mission

Mission type
Optical imaging
Use
Defense
Program
Zenit-4M
Country
Soviet Union
Builder
TsKBEM Filial No. 3
Platform (bus)
Zenit-4M

Launch

Date
March 6, 1973 · 09:20 UTC
Launch record
1973-012Success
Spaceport
Baikonur · pad LC31

Orbit and fate

Orbit class (GCAT)
LLEO/I
Perigee
173 km
Apogee
292 km
Inclination
65.01°
Status
Landed
Status date
March 20, 1973
Last known active
Mar 20, 1973
End of operations
Mar 20, 1973

Size

Mass
2,200 kg
Dry mass
2,200 kg
Total mass with attached objects
6,000 kg
Length
6.0 m
Diameter
2.20 m
Span
6.0 m

Source: GCAT payload, deep-space and lander catalogs, Jonathan C. McDowell (CC BY 4.0); Wikidata Q12753895 (CC0).