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NAVSTAR 51 (USA 166) (27663)
COSPAR: 2003-005A | Alt Name: GPS IIR-8
Image
Additional Sources
Launch Details
Launch Date
January 29, 2003
Launch Site
Launch Pad
SLC17B
Launch Vehicle
Delta 7925-9.5
Orbital Elements
NORAD ID
27663
International Designator
2003-005A
Epoch
Sat, 04 Jul 2026 01:31:03 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
54.88°
Right Ascension
214.30°
Eccentricity
Calculating...
Argument of Perigee
53.13°
Period
717.99 min
Mean Motion
2.01 rev/day
Latitude
Calculating...
Longitude
Calculating...
Altitude
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Velocity
Calculating...
Polar Plot
3D Visualization
Basic Satellite Info
Name
NAVSTAR 51 (USA 166)
Alternative Name
GPS IIR-8
Type
Payload
Status
Operational
Owner
AFSMC
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 27663U 03005A 26185.06323736 .00000070 00000-0 00000-0 0 9991
2 27663 54.8802 214.2982 0148096 53.1273 311.8752 2.00559687171659
Source: Celestrak
Summary
NAVSTAR 51 (also known as GPS IIR-8) is a navigation satellite launched on January 29, 2003, from Cape Canaveral Air Force Station's SLC17B launch pad using the Delta 7925-9.5 launch vehicle. It was manufactured by LMMS and has a configuration of AS-4000, part of the Series 4000 satellite series. The spacecraft measures approximately 1.5 meters in length and 1.9 meters in diameter with a span of 19.3 meters due to its solar arrays. It had a launch mass of 1077 kilograms and a dry mass of 910 kilograms, powered by two deployable solar arrays and batteries. Its mission is navigation as part of the GPS system, specifically designated as SVN 56. The satellite's shape is described as Box + 2 Pan with an RCS of 10. It was owned by AFSMC and has a projected lifetime of 10 years.
Physical Characteristics
Length
1.5
Diameter
1.9
Span
19.3
Dry Mass
910
Launch Mass
1077
Shape
Box + 2 Pan
Radar Cross Section
10
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
GPS SVN 56
Purpose
Navigation
Mission
Navigation
Manufacturer
LMMS
Life Expectancy
10 years
Bus
Series 4000
Configuration
AS-4000
Motor
Star 37XFP
Equipment
?
Power System
2 deployable solar arrays, 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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