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IRS-1B (21688)
COSPAR: 1991-061A | Alt Name: IRS-1B
Image
Additional Sources
Launch Details
Launch Date
August 29, 1991
Launch Site
Launch Pad
LC31
Launch Vehicle
Vostok 8A92M
Orbital Elements
NORAD ID
21688
International Designator
1991-061A
Epoch
Sat, 04 Jul 2026 06:54:17 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
99.41°
Right Ascension
193.66°
Eccentricity
Calculating...
Argument of Perigee
318.09°
Period
103.01 min
Mean Motion
13.98 rev/day
Latitude
Calculating...
Longitude
Calculating...
Altitude
Calculating...
Velocity
Calculating...
Polar Plot
3D Visualization
Basic Satellite Info
Name
IRS-1B
Alternative Name
IRS-1B
Type
Payload
Status
Non-operational
Owner
ISRO
Country
India
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 21688U 91061A 26185.28770663 -.00000104 00000-0 -40352-4 0 9998
2 21688 99.4106 193.6608 0023645 318.0928 55.4302 13.97874720670886
Source: Celestrak
Summary
IRS-1B is an Earth observation satellite operated by ISRO (Indian Space Research Organisation). It was launched on August 29, 1991, from the Tsemak Space Center using a Vostok 8A92M launch vehicle from LC31. The spacecraft measures 1.6 meters in length with a diameter of 1.1 meters and has a span of 12 meters when its solar arrays are deployed. It carries equipment including LISS-I, LISS-IIA/B for imaging purposes and is powered by two deployable solar arrays and batteries. IRS-1B has a dry mass of 960 kg and a launch mass of 990 kg. The satellite's shape is described as Box + 2 Pan with an RCS (Reflective Cross Section) value of 3.6711.
Physical Characteristics
Length
1.6
Diameter
1.1
Span
12
Dry Mass
960
Launch Mass
990
Shape
Box + 2 Pan
Radar Cross Section
3.6711
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
IRS-1B
Purpose
Earth observation
Mission
Earth observation
Manufacturer
ISRO
Life Expectancy
Unknown
Bus
IRS
Configuration
IRS-1 Bus
Motor
AOCS
Equipment
LISS-I, LISS-IIA/B
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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