Isro designing geo imaging satellite

Gisat will provide near real time pictures of large areas, under cloud free conditions, at frequent intervals

The Indian Space Research Organisation (Isro) is designing a Geo Imaging Satellite (Gisat). The Gisat will carry a GEO imager with multi-spectral (visible, near infra-red and thermal), multi-resolution (50 m to 1.5 km) imaging instruments. It will be placed in geostationary orbit of 36,000 km.

The remote sensing satellites launched by Isro revisit the same area once every two to 24 days and acquire images of a geographical strip (swath) at different spatial resolutions (360 metre to better than 1 metre). Gisat will provide near real time pictures of large areas of the country, under cloud-free conditions, at frequent intervals. That is, selected sector-wise image every 5 minutes and entire Indian landmass image every 30 minutes at 50m spatial resolution.

The total financial outlay for the project is Rs 392 crore, excluding the launch cost. The amount spent up to March 2012 is Rs 9.9 crore and BE provision of Rs 50 crore is made for the year 2012-2013, according to a release.

Gisat is planned to be launched during 2016-17.

Meanwhile, Isro has studied the palaeochannels (a remnant of an inactive river or stream channel that has been either filled or buried by younger sediment) in North West India and related them to the channels of River Saraswati. It has not constituted any committee for this purpose.

An integrated palaeochannel map of River Saraswati has been prepared from the origin in Himalayas to the Rann of Kutch. The origin of the mapped course of the River Saraswati palaeochannel in North West India was linked to Himalayan perennial source through Sutlej and Yamuna rivers.

The government has made efforts to trace the origin of Saraswati river and has also constituted a committee for this purpose.

The work on delineation of entire course of river ‘Saraswati’ in North West India was carried out using Indian Remote Sensing Satellite data along with digital elevation model. Satellite images are multi-spectral, multi-temporal and have advantages of synoptic view, which are useful to detect palaeochannels.

The palaeochannels are validated using historical maps, archaeological sites, hydro-geological and drilling data. It was observed that major Harappan sites of Kalibangan (Rajasthan), Banawali and Rakhigarhi (Haryana), Dholavira and Lothal (Gujarat) lie along the River Saraswati.

The Minister of State in the ministry of Personnel, PG & Pensions and in the Prime Minister’s Office V Narayanasamy gave this information in reply to a written question in the Lok Sabha on Wednesday.