Space Brief 29 Aug 2025
Today's Space Brief highlights emerging technologies in space, a contract for U.S. Space Force missions, developments in military operations, and updates on drone advancements.
SL-4 R/B (12955)
COSPAR: 1981-112B | Alt Name: Soyuz-U 39-429 Blok-I
DECAYED
Image
Additional Sources
Launch Details
Launch Date
November 13, 1981
Launch Site
Launch Pad
LC31
Launch Vehicle
Soyuz-U
Orbital Elements
NORAD ID
12955
International Designator
1981-112B
Decay Date
11/22/1981
Basic Satellite Info
Name
SL-4 R/B
Alternative Name
Soyuz-U 39-429 Blok-I
Type
Rocket Body
Status
Space Junk
Owner
RVSN
Country
USSR
Constellation
N/A
Related Satellites
Major Events
N/A
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
6.7
Diameter
2.7
Span
6.7
Dry Mass
2350
Launch Mass
2350
Shape
Cyl
Radar Cross Section
Unknown
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
11S510
Purpose
Unknown
Mission
Unknown
Manufacturer
PROG
Life Expectancy
Unknown
Bus
Blok-I
Configuration
Unknown
Motor
Unknown
Equipment
Unknown
Power System
Unknown
ADCS
Unknown
Transmitter Frequency
Unknown
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