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// calibration · 1971

TETR 4

TETR 4 was launched on September 29, 1971 aboard a Thor Delta N from Cape Canaveral & Kennedy. Latest status in GCAT: reentered (orbital decay) (Sep 19, 1978).

COSPAR 1971-083BNORAD 5492United States

Identity

Name in GCAT
TETR 3
Common name
TETR 4
Payload designation
ERS 33
Other names
TETR D:P
International designator
1971-083B
NORAD catalog number
5492
GCAT identifier
S05492
UN registration
A/AC.105/INF.242

Mission

Mission type
Calibration
Use
Civil government
Program
TTS
Owner
GSFC
Country
United States
Builder
TRW Inc.
Platform (bus)
ORS

Launch

Date
September 29, 1971 · 09:45 UTC
Launch record
1971-083Partial · 0.75
Spaceport
Cape Canaveral & Kennedy · pad LC17A

Orbit and fate

Orbit class (GCAT)
LLEO/I
Perigee
400 km
Apogee
571 km
Inclination
33.08°
Status
Reentered (orbital decay)
Status date
September 19, 1978
Last known active
1972
End of operations
1972

Size

Mass
18 kg
Dry mass
18 kg
Length
0.3 m
Diameter
0.30 m
Span
1.0 m

Source: GCAT payload, deep-space and lander catalogs, Jonathan C. McDowell (CC BY 4.0); Wikidata Q2848196 (CC0).