CERTIFICATE OF RE-ENTRYOrbital Register™ · by Orbital Radar™
Entry no.
1989-0826
OPS 5268 (CALSPHERE 4)
OPS 5268 (CALSPHERE 4) (NORAD 4958) re-entered Earth’s atmosphere on 20 September 1989, after 18 years, 7 months in orbit.
Official date
NORAD number
4958
International designator
1971-012D
Object type
Spacecraft
Country
United States
Launched
17 Feb 1971Vandenberg
Re-entered (UTC)
20 Sep 1989UTC calendar day
Time in orbit
18 years, 7 months6,790 days
How it ended
Re-entered (natural decay)
Latitude range
81.6°N to 81.6°SFinal inclination 98.4°
Mass
1 kg
Operator
NRL
Built by
NRL
Bus
NRL 10"
Programme
NRL Cal
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 98.4°, allowed a re-entry anywhere between 81.6°N and 81.6°S.
Life in orbit
18 years, 7 monthsOPS 5268 (CALSPHERE 4)’s lowest and highest points above Earth, week by week, from its tracking history.
From the same launch
1971-012
Entered in the Orbital Register™, founding volume, September 2026.
Record version 1 · No corrections · orbitalradar.com/register/1989-0826
© 2026 Orbital Radar. Cite this entry by its number; the register itself may not be copied.
Record version 1 · No corrections · orbitalradar.com/register/1989-0826
© 2026 Orbital Radar. Cite this entry by its number; the register itself may not be copied.