The successful launch of IRS 1C, one of the most advanced civilian earth observation satellite on December 26, 1995, has shown the world. India’s reliability in inexpensively launching its own Remote Sensing Satellite. Incorporating several advanced features, this satellite is designed to deliver a wide spectrum of services and is most advanced in the civilian remote sensing satellite at present, providing imagery of the highest resolution for the civilian remote sensing world market.
With the launch of its first operational class of remote sensing satellite IRS-1A, launched in 1988, IRS-1B in 1991, and IRS-P2 launched in October 1994 by the second development flight of the Indian launch vehicle PSLV, India has a fleet of remote sensing satellites, thereby establishing the most-desired continuity of resource from space. The enhanced capabilities of these satellites, including IRS-1D to be launched next year are expected to greatly contribute to the increasing application market.
The IRS 1C satellite takes only 93 minutes to go round the earth once and surveys the whole surface of the earth in just 24 days, providing continuous and operational remotely sensed data.
In view of the new capabilities of its sensors, this satellite has higher application potential than its predecessors. The IRS 1C satellite has three types of sophisticated imaging sensors, Panchromatic Camera, Linear Imaging and Self Scanning (LISS III) sensor and Wide Field Sensor (WIFS)
The Panchromatic camera is designed to provide data with a very high spatial resolution of 5.8 m and a ground swath of 70 km. The Linear Imaging and Self Scanning (LISS III) sensor provides mult-spectral data collected in four bands-two in the visible (0.51-0.59 and 0.62-0.68 microns), one in the near infra-red (0.77-0.86 microns) and one in short-wave infra-red (1.55-1.70 micron) regions of the electromagnetic spectrum. The Wide Field Sensor (WIFS) collects data in two spectral bands, visible (0.62-0.68microns) and near infra-red (0.77-0.86 microns) and has a wide ground swath of 810 kn with the spatial resolution of 188 m.
The whole-country forest map took seven years by application of remote sensing technologies whereas a ground based inventory would have taken fifty.
The data is supplied in the form of digital and photographic media. City geocoded products, Shift Along the Tract (SAT) products and Stereo pairs and vegetation Index Map (VIM) are some of the beneficial products for the users.
The management of the natural resources of the country and various other socially useful application is being done with the continuous and operational remote sensed data. Locating water resource all over the country has become easier using satellite pictures. Researchers found 180 wells in Rajasthan with a 92 percent success rate compared to the 40 percent success rate of conventional methods.
Remote sensing satellite have played a stellar role in forest and land use mapping. The whole country forest map took seven years by application of remote sensing technologies whereas a ground based inventory would have taken fifty. Remote sensing satellites also help in drought measuring and relief, mineral exploration and harvest and relief estimates. There are applications such as estimation of snow melt run off, which could be feasible only by the use of remote sensing. Such estimates are essential to predict inflows into reservoirs fed by snow melts.
Further advancement in remote sensing will help in improved spectral resolutions for crop and vegetation applications, especially to discriminate vegetation types, oceanic applications, including weather prediction and fisheries; atmospheric applications, specifically global change monitoring for meteorological users.