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OPTUS C1 (27831)
COSPAR: 2003-028B | Alt Name: Optus and Defense C1
Image
Additional Sources
Launch Details
Launch Date
June 11, 2003
Launch Site
FRGUI
Launch Pad
ELA3
Launch Vehicle
Ariane 5G
Orbital Elements
NORAD ID
27831
International Designator
2003-028B
Epoch
Fri, 03 Jul 2026 21:31:14 GMT
Apogee
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Perigee
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Inclination
6.93°
Right Ascension
69.21°
Eccentricity
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Argument of Perigee
30.07°
Period
1436.11 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
OPTUS C1
Alternative Name
Optus and Defense C1
Type
Payload
Status
Operational
Owner
OPTS
Country
Australia
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 27831U 03028B 26184.89669127 -.00000143 00000-0 00000-0 0 9992
2 27831 6.9286 69.2078 0005608 30.0667 301.2116 1.00271206 53222
Source: Celestrak
Summary
OPTUS C1, also known as Optus and Defense C1, is a communication satellite launched on June 11, 2003, from Guiana Space Centre using an Ariane 5G launch vehicle. It was manufactured by LOR/MELCO based on the SSL-1300 bus configuration. The satellite measures 8.2 meters in length and has a diameter of 7.8 meters with a span of 24.9 meters. Its dry mass is 1,978 kilograms and it had a launch mass of 4,725 kilograms. OPTUS C1 is equipped with 24 Ku-band transponders, 4 (+1) Ka-band transponders, 4 X-band transponders, and 6 UHF transponders for communication purposes. The power system includes two deployable solar arrays and batteries. It has a box shape with cruciform panels and an RCS of 25.1188. The satellite is owned by OPTS and operated for communication services.
Physical Characteristics
Length
8.2
Diameter
7.8
Span
24.9
Dry Mass
1978
Launch Mass
4725
Shape
Box + 2 Cruci Pan
Radar Cross Section
25.1188
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Optus C1/D
Purpose
Communication
Mission
Communication
Manufacturer
LOR/MELCO
Life Expectancy
Unknown
Bus
SSL-1300
Configuration
SSL-1300
Motor
R-4D-15-260
Equipment
24 Ku-band transponders, 4 (+1) Ka-band transponders, 4 X-band transponders, 6 UHF transponders
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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