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USA 157 (MILSTAR-2 2) (26715)
COSPAR: 2001-009A | Alt Name: Milstar 4
Image
Additional Sources
Launch Details
Launch Date
February 27, 2001
Launch Site
Launch Pad
SLC40
Launch Vehicle
Titan 401B/Centaur
Orbital Elements
NORAD ID
26715
International Designator
2001-009A
Epoch
Fri, 03 Jul 2026 16:38:36 GMT
Apogee
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Perigee
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Inclination
11.56°
Right Ascension
19.66°
Eccentricity
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Argument of Perigee
178.33°
Period
1436.12 min
Mean Motion
1.00 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 157 (MILSTAR-2 2)
Alternative Name
Milstar 4
Type
Payload
Status
Operational
Owner
AFSMC
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 26715U 01009A 26184.69347519 .00000117 00000-0 00000-0 0 9995
2 26715 11.5596 19.6559 0040113 178.3312 183.3039 1.00270118 33114
Source: Celestrak
Summary
USA 157 (MILSTAR-2 2), also known as Milstar 4, is a military communications satellite launched on February 27, 2001, from Cape Canaveral Air Force Station's SLC40 launch pad using the Titan 401B/Centaur vehicle. The spacecraft measures 15.5 meters in length and has a diameter of 5 meters with a span of 35 meters due to its deployable solar arrays. It carries Milstar DFS-4 payload including LDR, MDR, and Crosslink payloads for communications. With a dry mass of 4200 kilograms and launch mass of 4500 kilograms, the satellite is equipped with batteries for power storage and AOCS (Attitude and Orbit Control System) motors. Manufactured by LMMS, it was operated by AFSMC for its 10-year mission lifespan. The shape of the spacecraft consists of a truss structure combined with antennas for communication purposes.
Physical Characteristics
Length
15.5
Diameter
5
Span
35
Dry Mass
4200
Launch Mass
4500
Shape
Truss + Ant
Radar Cross Section
Unknown
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Milstar DFS-4
Purpose
Comsat
Mission
Comsat
Manufacturer
LMMS
Life Expectancy
10 years
Bus
Milstar
Configuration
Milstar Bus
Motor
AOCS
Equipment
LDR, MDR and Crosslink payloads
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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