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COSMOS 2172 (21789)
COSPAR: 1991-079A | Alt Name: Kosmos-2172
Image
Additional Sources
Launch Details
Launch Date
November 22, 1991
Launch Site
Launch Pad
LC81/23
Launch Vehicle
Proton-K/DM-2
Orbital Elements
NORAD ID
21789
International Designator
1991-079A
Epoch
Sat, 04 Jul 2026 05:23:46 GMT
Apogee
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Perigee
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Inclination
13.23°
Right Ascension
340.24°
Eccentricity
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Argument of Perigee
13.94°
Period
1436.45 min
Mean Motion
1.00 rev/day
Latitude
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Longitude
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Altitude
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Velocity
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Polar Plot
3D Visualization
Basic Satellite Info
Name
COSMOS 2172
Alternative Name
Kosmos-2172
Type
Payload
Status
Unknown
Owner
UNKSR
Country
USSR
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 21789U 91079A 26185.22484852 -.00000195 00000-0 00000-0 0 9996
2 21789 13.2350 340.2381 0003080 13.9354 345.2462 1.00246854 47524
Source: Celestrak
Summary
COSMOS 2172 (also known as Kosmos-2172) is a military relay satellite launched on November 22, 1991, from the TYMSC launch site using the Proton-K/DM-2 launch vehicle. Built by NPOPM and operating under UNKNOWN SOVIET AGENCY (UNKSR), the satellite has a length of 5.5 meters, diameter of 2.5 meters, and span of 9 meters. It carries Slav-2 and Sintez C-band transponders as part of its Geizer No. 18L payload configuration MSS-2500-GSO and was equipped with four SPT-70 Stationary Plasma Thrusters for propulsion. The satellite's power is derived from two deployable solar arrays and batteries, and it has a dry mass of 1900 kg and launch mass of 2100 kg. Its shape consists of a cylinder with two panels and a plate, featuring an RCS of 5.0118.
Physical Characteristics
Length
5.5
Diameter
2.5
Span
9
Dry Mass
1900
Launch Mass
2100
Shape
Cyl + 2 Pan + Plate
Radar Cross Section
5.0118
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Geizer No. 18L
Purpose
Military relay
Mission
Military relay
Manufacturer
NPOPM
Life Expectancy
Unknown
Bus
Geizer
Configuration
MSS-2500-GSO
Motor
4 x SPT-70 Stationary Plasma Thrusters
Equipment
Slav-2 and Sintez C-band transponders
Power System
2 deployable solar arrays, 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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