Space Brief 5 Jun 2025
Today's brief highlights a significant geospatial data collaboration between Maxar and Saab, defense budget discussions affecting satellite deployments, and the naming of new military command chiefs.
SL-4 R/B (12937)
COSPAR: 1981-109B | Alt Name: Soyuz-U 23-977 Blok-I
DECAYED
Image
Additional Sources
Launch Details
Launch Date
November 3, 1981
Launch Site
PLMSC
Launch Pad
LC41/1
Launch Vehicle
Soyuz-U
Orbital Elements
NORAD ID
12937
International Designator
1981-109B
Decay Date
11/6/1981
Basic Satellite Info
Name
SL-4 R/B
Alternative Name
Soyuz-U 23-977 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
Satellite Articles
View All Posts »Learn more about satellites and other related topics.
Space Brief 2 Dec 2024
Today's space updates include a new EU space commissioner's priorities, insights from declassified satellite images, and an update on NASA's Europa Clipper mission. A highlight in the Satellite Spotlight features the Russian satellite COSMOS 2070.
X Report 27 Jul 2025
SpaceX's rapid advancements continued this weekend with two consecutive Starlink missions and preparations for the upcoming Crew-11 launch, showcasing its efficiency and commitment to expanding satellite broadband coverage.
X Report 5 Feb 2025
SpaceX launches Maxar's high-resolution imaging satellites, Ontario reconsiders its Starlink contract, and the countdown to NASA's Lunar Trailblazer mission begins.
X Report 22 Nov 2025
Major challenges emerged with SpaceX's next-generation Starship booster testing, while Starlink deployments continued with successful launches.
Space Force Awards $437M to Viasat, SES for Military Satcom | KeepTrack Space Brief
Space Force contracts Viasat and SES for $437M Protected Tactical Satcom-Global program. Four new GEO satellites replace vulnerable single-satellite systems.
X Report 16 Dec 2024
SpaceX announces SPHEREx launch date for February 2025, and Airbus completes delivery of Thuraya 4 satellite for upcoming launch.
Falcon 9 Launches 25 Starlink Satellites After Weather Delays | KeepTrack X Report
SpaceX launches 25 Starlink satellites from Vandenberg after multiple weather delays. 20th Falcon 9 mission of 2026 features second-ever booster landing near The Bahamas.