IRS-1B
Indian Earth observation satellite From Wikipedia, the free encyclopedia
IRS-1B, Indian Remote Sensing satellite-1B, the second of the series of indigenous state-of-art remote sensing satellites, was successfully launched into a polar Sun-synchronous orbit on 29 August 1991 from the Soviet Cosmodrome at Baikonur. IRS-1B carries two sensors, LISS-1 and LISS-2, with resolutions of 72 m (236 ft) and 36 m (118 ft) respectively with a swath width of about 140 km (87 mi) during each pass over the country. It was a part-operational, part-experimental mission to develop Indian expertise in satellite imagery. It was a successor to the remote sensing mission IRS-1A, both undertaken by the Indian Space Research Organisation (ISRO).[3]
| Names | Indian Remote Sensing satellite-1B |
|---|---|
| Mission type | Earth observation |
| Operator | ISRO |
| COSPAR ID | 1991-061A |
| SATCAT no. | 21688 |
| Website | https://www.isro.gov.in/ |
| Mission duration | 3 years (planned) 10 years (achieved) |
| Spacecraft properties | |
| Spacecraft | IRS-1B |
| Bus | IRS-1 |
| Manufacturer | Indian Space Research Organisation |
| Launch mass | 975 kg (2,150 lb) |
| Dry mass | 895 kg (1,973 lb) |
| Dimensions | 1.56 m x 1.66 m x 1.10 m |
| Power | 600 watts |
| Start of mission | |
| Launch date | 29 August 1991, 06:48:43 UTC |
| Rocket | Vostok-2M s/n I15000-079 |
| Launch site | Baikonur Cosmodrome, Site 31 |
| Contractor | OKB-1 |
| Entered service | November 1991 [1] |
| End of mission | |
| Deactivated | 1 July 2001 [1] |
| Orbital parameters | |
| Reference system | Geocentric orbit[2] |
| Regime | Sun-synchronous orbit |
| Perigee altitude | 859 km (534 mi) |
| Apogee altitude | 915 km (569 mi) |
| Inclination | 99.2° |
| Period | 102.7 minutes |
| Instruments | |
| Linear Imaging Self-Scanning Sensor-1 (LISS-1) Linear Imaging Self-Scanning Sensor-2 (LISS-2) | |
IRS-1B was the second remote sensing mission to provide imagery for various land-based applications, such as agriculture, forestry, geology, and hydrology.[4]
Improved features compared to its predecessor (IRS-1A): gyroscope referencing for better orientation sensing, time tagged commanding facility for more flexibility in camera operation and line count information for better data product generation.[3]
The satellite was a box-shaped 1.56 m x 1.66 m x 1.10 metres bus with two Sun-tracking solar panels of 8.5 square metres each. Two nickel-cadmium batteries provided power during eclipses. The three-axis stabilised Sun-synchronous satellite had a 0.4° pitch/roll and 0.5° yaw pointing accuracy provided by a zero-momentum reaction wheel system utilising Earth/Sun/star sensors and gyroscopes.[4]
IRS-1B carried two solid state push broom scanner Linear Imaging Self-Scanning Sensor (LISS):
- LISS-1 (72 m (236 ft) each band ground resolution)
- LlSS-2 (36 m (118 ft) each band ground resolution) [5]
The satellite carried two LISS push broom CCD sensors operating in four spectral bands compatible with Landsat Thematic Mapper and Spot HRV data. The bands were 0.45-0.52, 0.52-0.59, 0.62-0.68, and 0.77-0.86 microns. The LISS-1 sensor had four 2048-element CCD imagers with a focal length of 162.2 cm (63.9 in) generating a resolution of 72 m (236 ft) and a 148 km (92 mi) swath width. The LISS-2 sensor had eight 2048-element CCD imagers with a focal length of 324.4 mm (12.77 in) generating a ground resolution of 36 m (118 ft) and a 74 km (46 mi) swath width. The LISS-2 imager bracketed the LISS-1 imager providing a 3 km (1.9 mi) overlap. Data from the LISS-1 were downlinked on S-band at 5.2 Mbps and from the LISS-2 at 10.4 Mbps to the ground station at Shadnagar, India. The satellite was controlled from Bangalore, India.[4]
IRS-1B was operated in a Sun-synchronous orbit. On 29 August 1991, it had a perigee of 859 km (534 mi), an apogee of 915 km (569 mi), an inclination of 99.2°, and an orbital period of 102.7 minutes.[2]
IRS-1B successfully completed its mission on 1 July 2001, after operating for 10 years.[1]
Wikiwand in your browser!
Seamless Wikipedia browsing. On steroids.
Every time you click a link to Wikipedia, Wiktionary or Wikiquote in your browser's search results, it will show the modern Wikiwand interface.
Wikiwand extension is a five stars, simple, with minimum permission required to keep your browsing private, safe and transparent.
