CERTIFICATE OF RE-ENTRYOrbital Register™ · by Orbital Radar™
Entry no.
1981-0505
OSO 1
OSO 1 (NORAD 255) re-entered Earth’s atmosphere on 8 October 1981, after 19 years, 7 months in orbit.
Official date
NORAD number
255
International designator
1962-006A
Object type
Spacecraft
Country
United States
Launched
7 Mar 1962Cape Canaveral
Re-entered (UTC)
8 Oct 1981UTC calendar day
Time in orbit
19 years, 7 months7,155 days
How it ended
Re-entered (natural decay)
Latitude range
32.8°N to 32.8°SFinal inclination 32.8°
Mass
208 kg
Operator
GSFC
Built by
Ball
Bus
OSO
Programme
OSO
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 32.8°, allowed a re-entry anywhere between 32.8°N and 32.8°S.
Life in orbit
19 years, 7 monthsOSO 1’s lowest and highest points above Earth, week by week, from its tracking history.
Also ended on 8 Oct 1981
1 entryFrom the same launch
1962-006
Entered in the Orbital Register™, founding volume, September 2026.
Record version 1 · No corrections · orbitalradar.com/register/1981-0505
© 2026 Orbital Radar. Cite this entry by its number; the register itself may not be copied.
Record version 1 · No corrections · orbitalradar.com/register/1981-0505
© 2026 Orbital Radar. Cite this entry by its number; the register itself may not be copied.