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STTW-5 (21833)
COSPAR: 1991-088A | Alt Name: Zhongxing 4
Image
Additional Sources
Launch Details
Launch Date
December 28, 1991
Launch Site
XICLF
Launch Pad
LC3
Launch Vehicle
Chang Zheng 3
Orbital Elements
NORAD ID
21833
International Designator
1991-088A
Epoch
Sun, 28 Jun 2026 16:22:25 GMT
Apogee
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Perigee
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Inclination
32.07°
Right Ascension
63.17°
Eccentricity
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Argument of Perigee
212.95°
Period
632.57 min
Mean Motion
2.28 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
STTW-5
Alternative Name
Zhongxing 4
Type
Payload
Status
Non-operational
Owner
CHIS
Country
China
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 21833U 91088A 26179.68223724 -.00000196 00000-0 00000-0 0 9999
2 21833 32.0699 63.1723 6556953 212.9548 79.7228 2.27643248359505
Source: Celestrak
Summary
STTW-5, also known as Zhongxing 4, is a communication satellite with the NORAD catalog ID 21833 and object ID 1991-088A. It was launched on December 28, 1991, from Xichang Satellite Launch Center (XICLF), using the Chang Zheng 3 launch vehicle from launch pad LC3. The satellite is owned by CHIS and manufactured by CAST, featuring a DFH-2 Bus configuration with dimensions of 1.6 meters in length, 2.1 meters in diameter, and span. It has a dry mass of 460 kg and was launched with the same mass. Equipped with two C-band transponders for communication purposes, STTW-5 uses solar cells and batteries for power supply. Its shape is described as cylindrical with antennas, and it has an RCS (radar cross-section) value of 5.4839.
Physical Characteristics
Length
1.6
Diameter
2.1
Span
2.1
Dry Mass
460
Launch Mass
460
Shape
Cyl + Ant
Radar Cross Section
5.4839
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
DFH 2A-4
Purpose
Communication
Mission
Communication
Manufacturer
CAST
Life Expectancy
Unknown
Bus
DFH-2
Configuration
DFH-2 Bus
Motor
AKM
Equipment
2 C-band transponders
Power System
Solar cells, 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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