Project Vanguard
How the U.S. Navy's Vanguard rocket became a Cold War icon, launched the world's oldest satellite still in orbit, and laid the groundwork for NASA's space exploration efforts.
COSMOS 2155 (21702)
COSPAR: 1991-064A | Alt Name: Kosmos-2155
Image
Additional Sources
Launch Details
Launch Date
September 13, 1991
Launch Site
Launch Pad
LC81/23
Launch Vehicle
Proton-K/DM-2
Orbital Elements
NORAD ID
21702
International Designator
1991-064A
Epoch
Sat, 04 Jul 2026 02:49:12 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
13.11°
Right Ascension
339.16°
Eccentricity
Calculating...
Argument of Perigee
241.89°
Period
1436.86 min
Mean Motion
1.00 rev/day
Latitude
Calculating...
Longitude
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Altitude
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Velocity
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Polar Plot
3D Visualization
Basic Satellite Info
Name
COSMOS 2155
Alternative Name
Kosmos-2155
Type
Payload
Status
Non-operational
Owner
PVO
Country
USSR
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 21702U 91064A 26185.11750507 .00000086 00000-0 00000-0 0 9994
2 21702 13.1068 339.1581 0002722 241.8881 294.4093 1.00218744127501
Source: Celestrak
Summary
COSMOS 2155, also known as Kosmos-2155, is an early warning satellite launched on September 13, 1991, from the Tyuratam Space Center using a Proton-K/DM-2 launch vehicle. It was designed and manufactured by NPOL/KOMET for the PVO (Russian Air Force) under the Oko program. The satellite measures 5 meters in length with a diameter of 2 meters and has a span of 10 meters due to its deployable solar arrays. At launch, it weighed 1250 kg, including fuel, and had a dry mass of 1150 kg. It is equipped with two deployable fixed solar arrays for power generation along with batteries. The satellite's mission is early warning, and it carries the Oko-S No. 7422 payload for this purpose. Its shape consists of a step cylinder with two panels.
Physical Characteristics
Length
5
Diameter
2
Span
10
Dry Mass
1150
Launch Mass
1250
Shape
Step Cyl + 2 Pan
Radar Cross Section
5.0119
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Oko-S No. 7422
Purpose
Early warning
Mission
Early warning
Manufacturer
NPOL/KOMET
Life Expectancy
Unknown
Bus
Oko
Configuration
Unknown
Motor
Unknown
Equipment
Unknown
Power System
2 deployable fixed 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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