Santa Maria Spaceport (Azores)
Europe's Atlantic outpost enters the launch business. How Portugal's first licensed spaceport in the Azores is preparing for suborbital flights in 2026 and positioning to receive ESA's Space Rider in 2028.
SL-4 DEB (21146)
COSPAR: 1991-016D | Alt Name: Sensor cover
DECAYED
Image
Additional Sources
Launch Details
Launch Date
March 6, 1991
Launch Site
PLMSC
Launch Pad
LC16/2
Launch Vehicle
Soyuz-U-PVB
Orbital Elements
NORAD ID
21146
International Designator
1991-016D
Decay Date
3/9/1991
Basic Satellite Info
Name
SL-4 DEB
Alternative Name
Sensor cover
Type
Debris
Status
Space Junk
Owner
UNKSR
Country
USSR
Constellation
N/A
Related Satellites
Major Events
N/A
Summary
Space debris, also known as space junk, encompasses all non-functional objects orbiting Earth such as defunct satellites, spent rocket stages, and fragments from collisions or disintegrations. Over time, this debris can accumulate and create an increasingly hazardous environment in orbit. Even tiny fragments, traveling at extremely high velocities, can inflict significant damage on operational satellites and spacecraft. If left unmanaged, the density of debris raises the risk of catastrophic collisions and further fragmentation, compounding the problem and threatening the safety and sustainability of space activities.
Physical Characteristics
Length
0
Diameter
0
Span
0
Dry Mass
0
Launch Mass
0
Shape
N/A
Radar Cross Section
Unknown
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Unknown
Purpose
Unknown
Mission
Unknown
Manufacturer
Unknown
Life Expectancy
Unknown
Bus
Unknown
Configuration
Unknown
Motor
Unknown
Equipment
Unknown
Power System
Unknown
ADCS
Unknown
Transmitter Frequency
Unknown
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