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
YAOGAN-39 04B (58143)
COSPAR: 2023-163C | Alt Name: Yaogan 39 04 zu 02 xing
Image
Additional Sources
Launch Details
Launch Date
October 23, 2023
Launch Site
XICLF
Launch Pad
LC3
Launch Vehicle
Chang Zheng 2D
Orbital Elements
NORAD ID
58143
International Designator
2023-163C
Epoch
Thu, 16 Jul 2026 07:56:54 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
34.99°
Right Ascension
186.98°
Eccentricity
Calculating...
Argument of Perigee
175.63°
Period
94.86 min
Mean Motion
15.18 rev/day
Latitude
Calculating...
Longitude
Calculating...
Altitude
Calculating...
Velocity
Calculating...
Polar Plot
3D Visualization
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Basic Satellite Info
Name
YAOGAN-39 04B
Alternative Name
Yaogan 39 04 zu 02 xing
Type
Payload
Status
Operational
Owner
ZZB
Country
China
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 58143U 23163C 26197.33118669 .00002046 00000+0 99991-4 0 9990
2 58143 34.9921 186.9810 0003423 175.6324 184.4419 15.17986864151748
Source: Celestrak
Summary
The YAOGAN-39 04B satellite, also known as Yaogan 39 04 zu 02 xing, was launched on October 23, 2023, from the Xichang Satellite Launch Center (LC3) using a Chang Zheng 2D launch vehicle. The satellite has dimensions of 2.5 meters in length and diameter with a span of 5 meters. Its dry mass is 300 kilograms, which is also its launch mass. Manufactured by SAST for the owner ZZB, it was designed for Earth observation or SIGINT purposes. Powered by solar arrays and batteries, the satellite has a box shape with two panels attached. Launched from China, its specific mission details remain uncertain but suggest involvement in either Earth observation or signals intelligence activities.
Physical Characteristics
Length
2.5
Diameter
2.5
Span
5
Dry Mass
300
Launch Mass
300
Shape
Box + 2 Pan
Radar Cross Section
Unknown
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Yaogan 39-04 B
Purpose
Earth observation or SIGINT ?
Mission
Earth observation or SIGINT ?
Manufacturer
SAST
Life Expectancy
Unknown
Bus
Unknown
Configuration
Unknown
Motor
Unknown
Equipment
Unknown
Power System
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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