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USA 21 (17506)
COSPAR: 1987-015A | Alt Name: USA 21
Image
Additional Sources
Launch Details
Launch Date
February 12, 1987
Launch Site
AFWTR
Launch Pad
SLC4W
Launch Vehicle
Titan 34B
Orbital Elements
NORAD ID
17506
International Designator
1987-015A
Epoch
Sun, 15 Feb 2026 03:28:01 GMT
Apogee
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Perigee
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Inclination
62.97°
Right Ascension
273.17°
Eccentricity
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Argument of Perigee
278.06°
Period
714.70 min
Mean Motion
2.01 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
USA 21
Alternative Name
USA 21
Type
Payload
Status
Unknown
Owner
NRO/SAFSP
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 17506U 87015A 26045.14445650 -.00000778 00000-0 -21159-2 0 9990
2 17506 62.9671 273.1681 7275603 278.0632 12.4511 2.01482512 42766
Source: Celestrak
Summary
USA 21 (also known as USA 21) is a communication satellite operated by NRO/SAFSP and manufactured by HSES on an HS-350 bus platform. Launched on February 12, 1987, from AFWTR using a Titan 34B launch vehicle, the satellite has dimensions of 7 meters in length with a diameter of 2.4 meters and a span of 7 meters. It had a launch mass of 800 kilograms and a dry mass of 650 kilograms. Equipped with solar cells mounted on its body and batteries for power storage, USA 21 carries the payload JUMPSEAT 8 (or QUASAR 7). The satellite's shape is described as cylindrical with two dishes attached. Its exact lifetime is not specified in the provided data.
Physical Characteristics
Length
7
Diameter
2.4
Span
7
Dry Mass
650
Launch Mass
800
Shape
Cyl + 2 Dish
Radar Cross Section
Unknown
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
JUMPSEAT 8 (or QUASAR 7)
Purpose
Communication
Mission
Communication
Manufacturer
HSES
Life Expectancy
Unknown
Bus
SDS
Configuration
HS-350 bus ?
Motor
?
Equipment
?
Power System
Solar cells (body mounted), batteries
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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