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RADIO 4 (13000)
COSPAR: 1981-120D | Alt Name: Radio RS-6
Image
Additional Sources
Launch Details
Launch Date
December 17, 1981
Launch Site
PLMSC
Launch Pad
LC132/2
Launch Vehicle
Kosmos 11K65M
Orbital Elements
NORAD ID
13000
International Designator
1981-120D
Epoch
Sat, 04 Jul 2026 00:59:45 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
82.96°
Right Ascension
51.22°
Eccentricity
Calculating...
Argument of Perigee
134.45°
Period
119.31 min
Mean Motion
12.07 rev/day
Latitude
Calculating...
Longitude
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Altitude
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Velocity
Calculating...
Polar Plot
3D Visualization
Basic Satellite Info
Name
RADIO 4
Alternative Name
Radio RS-6
Type
Payload
Status
Unknown
Owner
NPOPM/MAIO
Country
USSR
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 13000U 81120D 26185.04149968 .00000139 00000-0 14770-2 0 9993
2 13000 82.9598 51.2229 0018340 134.4505 22.1971 12.06921101962187
Source: Celestrak
Summary
RADIO 4, also known as Radio RS-6, is an amateur radio communication satellite launched on December 17, 1981, from the PLMSC launch site using a Kosmos 11K65M launch vehicle. The spacecraft has dimensions of 0.8 meters in length, diameter, and span with a dry mass of 70 kilograms and was manufactured by NPOPM/MAIO for amateur radio communication purposes. It is powered by solar cells and batteries and operates within a polyhedral shape with an RCS of 0.8179. The satellite's mission lasted approximately one year following its launch.
Physical Characteristics
Length
0.8
Diameter
0.8
Span
0.8
Dry Mass
70
Launch Mass
70
Shape
Poly
Radar Cross Section
0.8179
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
RS-6
Purpose
Amateur radio communication
Mission
Amateur radio communication
Manufacturer
NPOPM/MAIO
Life Expectancy
1 year
Bus
Strela-1M
Configuration
Unknown
Motor
None
Equipment
Unknown
Power System
Solar cells, batteries
ADCS
Unknown
Transmitter Frequency
Unknown
Map
Next Pass
Azimuth Elevation Time (Local)
Start Azimuth
Max Elevation
Stop Azimuth
Time Until
Pass Duration
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