IRS-1A Satellite (First Operational Satellite ) IRS-1A Satellite (First Operational Satellite )

This is first indigenously built sun-synchronous polar orbiting satellite.

Orbit Details

Launch date : March 17, 1988 (Soviet Launcher VOSTAK used)
Altitude : 904 Kms.
Inclination : 99.049 degrees
Period : 103.19266 minutes
Repetivity : 22 days
Equatorial crossong time : 10.25 AM descending
Weight : 975 Kg.

Imaging Sensor Characteristics (LISS-I and LISS-II Cameras)

Parameters	LISS-I	LISS-II
Focal Length	166.2	324.4
Field-of-view (deg)	9.4	4.7+4.7
Instantaneous field of view(IFOV) Microrad,	80	40
Detectors (CCDs)	2048 elements CCD	2048 elements CCD
Ground Resolution (m)	72.5	36.25
Spectral range (micro meter)	0.45 - 0.86	0.45 - 0.86
Number of Bands	4	4
Swath (Kms.)	148	74x2 ( LISS-A and LISS-B)
Radiometric Resolution (grey levels)	128	128
Data rate (Mbps)	5.2	10.4x2
Weight (Kgs)	38.5	80.8x2
Power (Watts)	34	34x2

* LISS -Linear Imaging Self-Scanning Sensor, CCD charge coupled devices.
* LISS-II contains two separate identical sensors LISS-A and LISS-B with a spatial resolution of 36.25 each.
* The 4 bands are:
B1 - 0.42-0.52 (blue)
B2 - 0.52-0.59 (green)
B3 - 0.62-0.68 (red)
B4 - 0.77-0.86 (near IR)
The bands are similar to the LANDSAT 1, 2, 3 and 4 bands.