It is located at 74 degree East longitude. Its first name was METSAT. It was later renamed as KALPANA-1 to commemorate Kalpana Chawla. Launched in December 2005 by the European Ariane launch vehicle, INSAT-4A is positioned at 83 degree East longitude along with INSAT-2E and INSAT-3B. INSAT-A carries 12 Ku band 36 MHz bandwidth transponders employing 140 W TWTAs to provide an EIRP of 52 dBW at the edge of coverage polygon with footprint covering Indian main land and 12 C-band 36 MHz bandwidth transponders provide an EIRP of 39 dBW at the edge of coverage with expanded radiation patterns encompassing Indian geographical boundary, area beyond India in southeast and northwest regions. Tata Sky, a joint venture between the TATA Group and STAR uses INSAT-4A for distributing their DTH service. It was launched in March 2007 by the European Ariane launch vehicle. Configured with payloads identical to that of INSAT-4A, INSAT-4B carries 12 Ku band and 12 C-band transponders to provide EIRP of 52 dBW and 39 dBW respectively. Two Tx/Rx dual grid offset fed shaped beam reflectors of 2.2 m diameter for Ku band and 2 m diameter for C-band are used. INSAT-4B augments the high power transponder capacity over India in Ku band and over a wider region in C-band. It is co-located with INSAT-3A at 93.5 degree E longitude. The national space agency Indian Space Research Organisation (ISRO) has allotted nearly seven Ku band transponders to Sun Direct; a DTH service provider from South India, and the other five to Doordarshan's DD Direct Plus. 12 transponders in the C band are for TV, radio and telecommunication purposes  American cyber warfare expert Jeffrey Carr, who specialises in investigations of cyber attacks against government, mentioned in his interview with The Times of India, that the reason for this power glitch may have been an infection by the sophisticated Stuxnet worm. He attributed the development of Stuxnet worm most likely to Government of China which had the necessary sophistication to develop the bug and would gain the maximum by failure of Indian satellite. He also pointed out that Stuxnet was discovered just a month before the Indian satellite was hit by the power glitch, the reason for which still remains unknown.