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ASTRA 1B (21139)
COSPAR: 1991-015A | Alt Name: Astra 1B
Image
Additional Sources
Launch Details
Launch Date
March 2, 1991
Launch Site
FRGUI
Launch Pad
ELA2
Launch Vehicle
Ariane 44LP
Orbital Elements
NORAD ID
21139
International Designator
1991-015A
Epoch
Fri, 03 Jul 2026 22:04:25 GMT
Apogee
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Perigee
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Inclination
13.39°
Right Ascension
22.10°
Eccentricity
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Argument of Perigee
13.74°
Period
1461.74 min
Mean Motion
0.99 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
ASTRA 1B
Alternative Name
Astra 1B
Type
Payload
Status
Non-operational
Owner
SES
Country
Luxembourg
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 21139U 91015A 26184.91973838 -.00000239 00000-0 00000-0 0 9996
2 21139 13.3879 22.0955 0008533 13.7419 7.6102 0.98512664116450
Source: Celestrak
Summary
ASTRA 1B (OBJECT_ID: 1991-015A) is a communication satellite designed for direct broadcasting purposes and was launched on March 2, 1991, from the Guiana Space Centre’s ELA2 launch pad using an Ariane 44LP vehicle. It has dimensions of 2.9 meters in length, 2.2 meters in diameter, and a span of 24.4 meters, with a dry mass of 1,177 kilograms and was manufactured by GEEW for the owner SES. The satellite is equipped with 16 (+6) Ku-band transponders and powered by two deployable solar arrays along with batteries. Its structure consists of a box shape with two panels (SHAPE: Box + 2 Pan), and it has a surface area of 8.6808 square meters (RCS). The satellite's propulsion system includes two Leros 1 motors, and its design life expectancy is 12 years.
Physical Characteristics
Length
2.9
Diameter
2.2
Span
24.4
Dry Mass
1177
Launch Mass
2580
Shape
Box + 2 Pan
Radar Cross Section
8.6808
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Astra 1B
Purpose
Communication (Direct Broadcasting)
Mission
Communication (Direct Broadcasting)
Manufacturer
GEEW
Life Expectancy
12 years
Bus
AS5000
Configuration
AS-5000
Motor
2x Leros 1
Equipment
16 (+6) Ku-band 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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