X Report 27 Apr 2025
SpaceX gears up for two major Starlink launches, while regulatory challenges slow progress in India.
EXPLORER 21 (IMP-2) (00889)
COSPAR: 1964-060A | Alt Name: IMP 2
DECAYED
Image
Additional Sources
Launch Details
Launch Date
October 4, 1964
Launch Site
Launch Pad
LC17A
Launch Vehicle
Thor Delta C
Orbital Elements
NORAD ID
00889
International Designator
1964-060A
Decay Date
1/30/1966
Explore in the Catalog
Basic Satellite Info
Name
EXPLORER 21 (IMP-2)
Alternative Name
IMP 2
Type
Payload
Status
Decayed
Owner
GSFC
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
Summary
Apologies, there is no summary for this satellite yet. I am working to generate these for every object in the catalog, but it is going to take time.
Physical Characteristics
Length
0.2
Diameter
0.7
Span
2.5
Dry Mass
62
Launch Mass
62
Shape
Oct Cyl + 2 Pan + 2 Ant
Radar Cross Section
Unknown
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
IMP B
Purpose
Unknown
Mission
Unknown
Manufacturer
GSFC
Life Expectancy
Unknown
Bus
IMP
Configuration
Unknown
Motor
Unknown
Equipment
Unknown
Power System
Unknown
ADCS
Unknown
Transmitter Frequency
Unknown
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