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Today's brief covers SpaceX's Starship launch approval, Antares' nuclear funding, and shifts in global space defense strategies.
SL-8 R/B (18121)
COSPAR: 1987-051J | Alt Name: Kosmos-3M 26-184 Stage 2
Image
Additional Sources
Launch Details
Launch Date
June 16, 1987
Launch Site
PLMSC
Launch Pad
LC132/1
Launch Vehicle
Kosmos 11K65M
Orbital Elements
NORAD ID
18121
International Designator
1987-051J
Epoch
Fri, 03 Jul 2026 09:36:04 GMT
Apogee
Calculating...
Perigee
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Inclination
74.01°
Right Ascension
157.61°
Eccentricity
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Argument of Perigee
107.80°
Period
117.78 min
Mean Motion
12.23 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
SL-8 R/B
Alternative Name
Kosmos-3M 26-184 Stage 2
Type
Rocket Body
Status
Space Junk
Owner
RVSN
Country
USSR
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 18121U 87051J 26184.40004914 -.00000099 00000-0 -77833-3 0 9998
2 18121 74.0063 157.6077 0131292 107.7956 8.4985 12.22604977742569
Source: Celestrak
Summary
A rocket body, also commonly referred to as an upper stage or spent rocket stage, is the structural shell left behind after a rocket has delivered its payload to orbit. These large and often heavy pieces of space hardware can remain in orbit for years, posing significant collision hazards as part of the growing space debris problem. If left uncontrolled, rocket bodies have the potential to reenter Earth's atmosphere unpredictably, which can lead to falling debris in populated areas. Additionally, they risk colliding with operational satellites or the International Space Station, creating more debris and putting human life at risk.
Physical Characteristics
Length
4.2
Diameter
2.4
Span
4.2
Dry Mass
1434
Launch Mass
1434
Shape
Cyl
Radar Cross Section
6.0226
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
S3M
Purpose
Unknown
Mission
Unknown
Manufacturer
OAZ
Life Expectancy
Unknown
Bus
S3
Configuration
Unknown
Motor
Unknown
Equipment
Unknown
Power System
Unknown
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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