X Report 17 Jun 2025
SpaceX successfully launched 26 Starlink satellites from California, preparing for upcoming crewed missions to the ISS.
SL-4 R/B (20321)
COSPAR: 1989-088B | Alt Name: Soyuz-U 39-725 Blok-I
DECAYED
Image
Additional Sources
Launch Details
Launch Date
November 17, 1989
Launch Site
Launch Pad
LC1
Launch Vehicle
Soyuz-U
Orbital Elements
NORAD ID
20321
International Designator
1989-088B
Decay Date
11/19/1989
Basic Satellite Info
Name
SL-4 R/B
Alternative Name
Soyuz-U 39-725 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.
CelesTrak.org
An in-depth look at CelesTrak, the leading non-profit provider of orbital element sets and collision assessment tools, trusted by space professionals worldwide.
SpaceX Names AI Megaconstellation "Starmind" | KeepTrack X Report
SpaceX officially names its planned AI megaconstellation Starmind while a Falcon 9 upper stage targets a lunar impact this August.
X Report 17 Sep 2025
Today’s highlights include successful Falcon 9 launch for MECANO ID, ongoing Starship Block 3 development, and plans for direct-to-device testing next year.
X Report 25 Jun 2025
SpaceX successfully launched the historic Axiom-4 mission to the ISS, marking a significant milestone in private space travel, while also expanding Starlink's reach into Vietnam's healthcare sector.
Space Brief 17 Jun 2025
Today's space brief covers key developments in satellite monitoring, U.K. defense contracts, and critical licensing reforms supporting national security.
NASA Expands SpaceX Crew Contract as Boeing Stalls | KeepTrack X Report
NASA adds crew missions to SpaceX's contract as Boeing Starliner certification stalls, while Falcon 9 hits its 60th orbital launch of 2026.
Space Brief 2 Nov 2025
Today's briefing covers India's military communications satellite launch, SpaceX's Starlink mission milestone, Latvia's agreement to the Artemis Accords, and more significant updates in space technology and satellite launches.