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COSMOS 1851 (18103)
COSPAR: 1987-050A | Alt Name: Kosmos-1851
Image
Additional Sources
Launch Details
Launch Date
June 12, 1987
Launch Site
PLMSC
Launch Pad
LC43/4
Launch Vehicle
Molniya 8K78M
Orbital Elements
NORAD ID
18103
International Designator
1987-050A
Epoch
Fri, 26 Jun 2026 03:49:23 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
70.95°
Right Ascension
187.32°
Eccentricity
Calculating...
Argument of Perigee
38.92°
Period
718.37 min
Mean Motion
2.00 rev/day
Latitude
Calculating...
Longitude
Calculating...
Altitude
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Velocity
Calculating...
Polar Plot
3D Visualization
Basic Satellite Info
Name
COSMOS 1851
Alternative Name
Kosmos-1851
Type
Payload
Status
Unknown
Owner
PVO
Country
USSR
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 18103U 87050A 26177.15930494 .00000151 00000-0 00000-0 0 9998
2 18103 70.9466 187.3218 4656316 38.9178 356.5709 2.00453009285973
Source: Celestrak
Summary
COSMOS 1851, also known as Kosmos-1851, is an early warning satellite launched on June 12, 1987, from the Plesetsk Cosmodrome using a Molniya 8K78M launch vehicle. The spacecraft, part of the Oko system and manufactured by NPOL/KOMET for the Soviet Air Defense Forces (PVO), measures 4 meters in length with a diameter of 2 meters and a span of 5 meters. It has a dry mass of 1150 kg and was launched with a total mass of 1250 kg. Its primary mission is to provide early warning, supported by two deployable fixed solar arrays and batteries for power. The satellite features a cylindrical shape with two panoramic cameras, designed to operate in space since its launch date.
Physical Characteristics
Length
4
Diameter
2
Span
5
Dry Mass
1150
Launch Mass
1250
Shape
Cyl + 2 Pan
Radar Cross Section
11.8549
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Oko 73D6 No. 6041
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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