The Day America Pioneered Polar Orbits
Sixty-six years ago, a Thor-Agena rocket thundered into the California sky carrying Discoverer 1, the first satellite attempt at polar orbit and the secret vanguard of Americas space reconnaissance program
SL-16 DEB (18410)
COSPAR: 1987-041C | Alt Name: Sep Motor Cover
Image
Additional Sources
Launch Details
Launch Date
May 13, 1987
Launch Site
Launch Pad
LC45/1
Launch Vehicle
Zenit-2
Orbital Elements
NORAD ID
18410
International Designator
1987-041C
Epoch
Sat, 04 Jul 2026 04:44:47 GMT
Apogee
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Perigee
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Inclination
70.99°
Right Ascension
84.99°
Eccentricity
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Argument of Perigee
29.25°
Period
104.79 min
Mean Motion
13.74 rev/day
Latitude
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Longitude
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Altitude
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Velocity
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Polar Plot
3D Visualization
Basic Satellite Info
Name
SL-16 DEB
Alternative Name
Sep Motor Cover
Type
Debris
Status
Space Junk
Owner
UNKS
Country
USSR
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 18410U 87041C 26185.19777262 .00000109 00000-0 13917-3 0 9991
2 18410 70.9851 84.9908 0200964 29.2514 124.3970 13.74132182961260
Source: Celestrak
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
1
Span
1
Dry Mass
1
Launch Mass
1
Shape
Cone
Radar Cross Section
0.092
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Sep Motor Cover
Purpose
Unknown
Mission
Unknown
Manufacturer
YUZH
Life Expectancy
Unknown
Bus
Sep Motor Cover
Configuration
Unknown
Motor
Unknown
Equipment
Unknown
Power System
Unknown
ADCS
Unknown
Transmitter Frequency
Unknown
Map
Next Pass
Azimuth Elevation Time (Local)
Start Azimuth
Max Elevation
Stop Azimuth
Time Until
Pass Duration
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