CERTIFICATE OF RE-ENTRYOrbital Register™ · by Orbital Radar™
Entry no.
2025-0757
SL-6 R/B(2)
SL-6 R/B(2) (NORAD 11550) re-entered Earth’s atmosphere on 10 April 2025, after 45 years, 7 months in orbit.
Official date
NORAD number
11550
International designator
1979-077D
Object type
Rocket body
Country
USSR
Launched
28 Aug 1979Plesetsk Cosmodrome
Re-entered (UTC)
10 Apr 2025UTC calendar day
Time in orbit
45 years, 7 months16,662 days
How it ended
Re-entered (natural decay)
Latitude range
61.9°N to 61.9°SFinal inclination 61.9°
Mass
4,500 kg
Where it came down
Latitude band its orbit allowedExact position not recorded
No position was recorded for this re-entry. Its final orbit, inclined at 61.9°, allowed a re-entry anywhere between 61.9°N and 61.9°S.
Life in orbit
45 years, 7 monthsSL-6 R/B(2)’s lowest and highest points above Earth, week by week, from its tracking history.
Also ended on 10 Apr 2025
14 entriesFrom the same launch
1979-077
Entered in the Orbital Register™, founding volume, September 2026.
Record version 1 · No corrections · orbitalradar.com/register/2025-0757
© 2026 Orbital Radar. Cite this entry by its number; the register itself may not be copied.
Record version 1 · No corrections · orbitalradar.com/register/2025-0757
© 2026 Orbital Radar. Cite this entry by its number; the register itself may not be copied.