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NAVSTAR 46 (USA 145) (25933)
COSPAR: 1999-055A | Alt Name: GPS IIR-3
Image
Additional Sources
Launch Details
Launch Date
October 7, 1999
Launch Site
Launch Pad
SLC17A
Launch Vehicle
Delta 7925-9.5
Orbital Elements
NORAD ID
25933
International Designator
1999-055A
Epoch
Fri, 03 Jul 2026 17:52:18 GMT
Apogee
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Perigee
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Inclination
51.45°
Right Ascension
294.74°
Eccentricity
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Argument of Perigee
176.49°
Period
717.98 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
NAVSTAR 46 (USA 145)
Alternative Name
GPS IIR-3
Type
Payload
Status
Backup
Owner
AFSMC
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 25933U 99055A 26184.74466350 -.00000051 00000-0 00000-0 0 9993
2 25933 51.4477 294.7442 0106509 176.4933 180.9720 2.00561478195902
Source: Celestrak
Summary
NAVSTAR 46 (USA 145), also known as GPS IIR-3, is a satellite launched by the United States on October 7, 1999, from Cape Canaveral Air Force Station using a Delta 7925-9.5 launch vehicle. The spacecraft has dimensions of 1.5 meters in length and 1.9 meters in diameter with a span of 19.3 meters, equipped for navigation purposes as part of the GPS system. It features two deployable solar arrays and batteries for power generation. With a dry mass of 910 kg and launch mass of 1077 kg, it was manufactured by LMMS (Lockheed Martin Missiles & Space). Its mission is to provide navigation services with an expected lifetime of 10 years. The satellite has a box shape with two panels and a radar cross section (RCS) of 3.981 m².
Physical Characteristics
Length
1.5
Diameter
1.9
Span
19.3
Dry Mass
910
Launch Mass
1077
Shape
Box + 2 Pan
Radar Cross Section
3.981
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
GPS SVN 46
Purpose
Navigation
Mission
Navigation
Manufacturer
LMMS
Life Expectancy
10 years
Bus
GPS IIR
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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