The Rohini RS-D1 is an experimental satellite that was developed by ISRO to study the propagation of radio waves in the ionosphere. The satellite was launched on May 31, 1981 from SHAR Centre, Sriharikota, India and had a mission life of up to 1.2 years. This mission was carried out in SLV-3 launch vehicle and has a mass of 20 Kg. The launch was a partial success as the satellite did not reach the intended height and thus it stayed in orbit for only 9 days. The satellite carried a solid-state camera using linear array of detectors for remote sensing applications. It carried scientific instruments to conduct experiments related to atmospheric studies and to test satellite technologies developed by India's space scientists and engineers.