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Explorer 21
American satellite of Explorers program. Explorer 21 was launched on October 4, 1964 aboard a Thor Delta C from Cape Canaveral & Kennedy. Latest status in GCAT: reentered (orbital decay) (January 1966).
COSPAR 1964-060ANORAD 889United States
Identity
- Name in GCAT
- IMP 2
- Common name
- Explorer 21
- Payload designation
- IMP B
- Other names
- Explorer 21
- International designator
- 1964-060A
- NORAD catalog number
- 889
- GCAT identifier
- S00889
- UN registration
- A/AC.105/INF.085
Mission
- Mission type
- Space science
- Use
- Civil government
- Program
- IMP
- Owner
- GSFC
- Country
- United States
- Builder
- NASA Goddard Space Flight Center
- Platform (bus)
- IMP
Launch
- Date
- October 4, 1964 · 03:45 UTC
- Launch record
- 1964-060Success
- Rocket
- Thor Delta C
- Spaceport
- Cape Canaveral & Kennedy · pad LC17A
Orbit and fate
- Orbit class (GCAT)
- VHEO
- Perigee
- 666 km
- Apogee
- 94,526 km
- Inclination
- 33.82°
- Status
- Reentered (orbital decay)
- Status date
- January 1966
- Last known active
- Oct 13, 1965
- End of operations
- Oct 13, 1965
Size
- Mass
- 62 kg
- Dry mass
- 62 kg
- Length
- 0.2 m
- Diameter
- 0.70 m
- Span
- 2.5 m
Source: GCAT payload, deep-space and lander catalogs, Jonathan C. McDowell (CC BY 4.0); Wikidata Q3736074 (CC0).