ISRO’s RISAT-1 was decommissioned last year

Researchers in Kerala are turning to foreign space agencies to source satellite radar imagery for post-flood analysis and damage assessment as the decommissioning of ISRO’s RISAT-1 last year has left India without an indigenous radar imaging satellite for civilian applications. While the University of Kerala has tied up with the Michigan Technological University to map the areas that were flooded last month following torrential rains in the State, the Kerala Agricultural University has partnered with the Tamil Nadu Agricultural University to assess the crop damage. The research teams are sourcing radar images from the European Space Agency (ESA) and the Canadian Space Agency to prepare inundation maps.

Radar imaging satellites like ESA’s Sentinel and ISRO’s RISAT are particularly useful for monitoring floods and assessing damage because they are capable of penetrating cloud cover and operating day and night and in all weather conditions.

“RISAT-1 is no longer operational. It was decommissioned last year,” ISRO Chairman K. Sivan told The Hindu. Launched on April 26, 2012, the satellite was equipped with a C-band synthetic aperture radar for earth observation and had a design life of five years.

In 2016, U.S. space agency NASA had reported a ‘debris generating’ event near RISAT-1. In 2017, the satellite was decommissioned and declared non-operational in the annual report of the Department of Space. RISAT- 2, another satellite in the series that was built by Israel Aerospace Industries and launched in 2009, remains in orbit but is reserved for strategic applications.

“Notwithstanding the absence of our own radar satellite, ISRO is equipped with microwave data acquired under various international charters”, said P.G.Diwakar, former Scientific Secretary to the Chairman, ISRO. “Most of the data is published on the Bhuvan website and can be accessed by the Government and other institutions for post-flood analysis.” Researchers stress the need for ISRO to focus on the development of a successor to RISAT-1. The increasing frequency of climate-change induced events in the country warrants a dedicated indigenous satellite resource, they contend.