CERTIFICATE OF RE-ENTRYOrbital Register™ · by Orbital Radar™
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Entry no.
1977-0514

PROGNOZ 4

PROGNOZ 4 (NORAD 8510) re-entered Earth’s atmosphere on 18 December 1977, after 1 year, 11 months in orbit.

Official date
NORAD number
8510
International designator
1975-122A
Object type
Spacecraft
Country
USSR
Launched
22 Dec 1975Baikonur Cosmodrome
Re-entered (UTC)
18 Dec 1977UTC calendar day
Time in orbit
1 year, 11 months727 days
How it ended
Re-entered (natural decay)
Latitude range
—
Mass
905 kg
Operator
IKI / Babakin
Built by
Lavochkin
Bus
SO-M
Programme
SO-M

Where it came down

Not on record

No position was recorded for this re-entry. Its final orbit is not on record.

Life in orbit

1 year, 11 months

Also ended on 18 Dec 1977

1 entry
1977-0515SL-4 R/B

From the same launch

1975-122
1976-0046SL-6 R/B
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Entered in the Orbital Register™, founding volume, September 2026.
Record version 1 · No corrections · orbitalradar.com/register/1977-0514
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