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// astronomy · 1961

Explorer 11

Space observatory. Explorer 11 was launched on April 27, 1961 aboard a Juno II from Cape Canaveral & Kennedy. Latest status in GCAT: in orbit, attached to another object.

COSPAR 1961 NU 1NORAD 107United States

Identity

Name in GCAT
Explorer 11
Payload designation
NASA S-15
International designator
1961 NU 1
NORAD catalog number
107
GCAT identifier
S00107
UN registration
A/AC.105/INF.001

Mission

Mission type
Astronomy
Use
Civil government
Program
ExplorerG
Owner
GSFC
Country
United States
Builder
NASA Marshall Space Flight Center
Platform (bus)
S-15

Launch

Date
April 27, 1961 · 14:16 UTC
Launch record
1961 NUSuccess
Rocket
Juno II
Spaceport
Cape Canaveral & Kennedy · pad LC26B

Orbit and fate

Orbit class (GCAT)
LEO/I
Perigee
497 km
Apogee
1,777 km
Inclination
28.76°
Status
In orbit, attached to another object
Last known active
Dec 6, 1961
End of operations
Dec 6, 1961

Size

Mass
40 kg
Dry mass
40 kg
Total mass with attached objects
45 kg
Length
1.1 m
Diameter
0.30 m
Span
1.1 m

Source: GCAT payload, deep-space and lander catalogs, Jonathan C. McDowell (CC BY 4.0); Wikidata Q49695 (CC0).