Starlink Constellation Size Hits 9,931, X Report 7 Mar 2026
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PEGASUS R/B (21587)
COSPAR: 1991-051H | Alt Name: Pegasus F02 Stage 4
DECAYED
Image
Additional Sources
Launch Details
Launch Date
July 17, 1991
Launch Site
AFWTR
Launch Pad
RW04/22
Launch Vehicle
Pegasus/HAPS
Orbital Elements
NORAD ID
21587
International Designator
1991-051H
Decay Date
11/8/1991
Basic Satellite Info
Name
PEGASUS R/B
Alternative Name
Pegasus F02 Stage 4
Type
Rocket Body
Status
Space Junk
Owner
OSCC
Country
United States
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
0.8
Diameter
1
Span
1
Dry Mass
97
Launch Mass
97
Shape
Sphere + Cone
Radar Cross Section
0.5875
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
HAPS 1
Purpose
Unknown
Mission
Unknown
Manufacturer
OSCC
Life Expectancy
Unknown
Bus
HAPS
Configuration
Unknown
Motor
Unknown
Equipment
Unknown
Power System
Unknown
ADCS
Unknown
Transmitter Frequency
Unknown
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