GSAT-4
GSAT-4, also known as HealthSat was an experimental satellite launched on 15 April 2010. Due to failure in the upper cyrogenic stage of the GSLV launch rocket, the satellite was lost in sea. The satelitte was to test various new technologies including the GPS-aided geo-augmented navigation system. If the launch had been successful, then GSAT-4 would have been one of the heaviest satellites launched by India.
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