Space Brief 18 Apr 2025
Today's highlights include a Minotaur IV launch of U.S. spy satellites, Rocket Lab's new defense contracts, and the unveiling of Space Force's warfighting framework. Plus, the Satellite Spotlight dives into METEOR 3-1.
SL-4 R/B (07926)
COSPAR: 1975-053B | Alt Name: Soyuz-U 41-850 Blok-I
DECAYED
Image
Additional Sources
Launch Details
Launch Date
June 12, 1975
Launch Site
PLMSC
Launch Pad
LC43/3
Launch Vehicle
Soyuz-U
Orbital Elements
NORAD ID
07926
International Designator
1975-053B
Decay Date
6/20/1975
Basic Satellite Info
Name
SL-4 R/B
Alternative Name
Soyuz-U 41-850 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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