Space Brief 31 Jul 2025
Today's Space Brief brings updates on the U.S. Space Force's upcoming missions, in-space technology strategies, the challenges faced by new launchers, and advancements in satellite communication.
SL-4 R/B (25859)
COSPAR: 1999-038B | Alt Name: Soyuz-U-PVB No. 667 Blok-I
DECAYED
Image
Additional Sources
Launch Details
Launch Date
July 16, 1999
Launch Site
Launch Pad
LC1
Launch Vehicle
Soyuz-U-PVB
Orbital Elements
NORAD ID
25859
International Designator
1999-038B
Decay Date
7/19/1999
Basic Satellite Info
Name
SL-4 R/B
Alternative Name
Soyuz-U-PVB No. 667 Blok-I
Type
Rocket Body
Status
Space Junk
Owner
RVSNR
Country
Russia
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
22.1
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
11S510
Purpose
Unknown
Mission
Unknown
Manufacturer
PROGT
Life Expectancy
Unknown
Bus
Blok-I
Configuration
Unknown
Motor
Unknown
Equipment
Unknown
Power System
Unknown
ADCS
Unknown
Transmitter Frequency
Unknown
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