Launch Date
August 25, 1964
Launch Site
AFWTR
Launch Pad
PALC-D
Launch Vehicle
Scout X-4
NORAD ID
00870
International Designator
1964-051A
Epoch
Sat, 04 Jul 2026 04:58:00 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
79.90°
Right Ascension
260.22°
Eccentricity
Calculating...
Argument of Perigee
238.49°
Period
103.46 min
Mean Motion
13.92 rev/day
Latitude
Calculating...
Longitude
Calculating...
Altitude
Calculating...
Velocity
Calculating...
Name
EXPLORER 20
Alternative Name
Explorer 20
Type
Status
Owner
GSFC
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
1 00870U 64051A 26185.20694656 .00000143 00000-0 10327-3 0 9995
2 00870 79.8978 260.2185 0096331 238.4874 120.6845 13.91794230135809
Source: Celestrak
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.
Length
0.8
Diameter
0.7
Span
37
Dry Mass
44
Launch Mass
44
Shape
DCone + 6 Ant
Radar Cross Section
0.4927
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Payload
NASA S-48
Purpose
Research
Mission
Research
Manufacturer
CHAIL
Life Expectancy
Unknown
Bus
S-48
Configuration
Unknown
Motor
None
Equipment
Fixed-Frequency Ionosonde, Spherical Ion-Mass Spectrometer, six sounding antennas
Power System
Solar cells, batteries
ADCS
Unknown
Transmitter Frequency
Unknown
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