Chennai: After the successful demonstration of the fourth stage engine (PS-4) for experiments in space last month, the Indian Space Research Organisation (ISRO) is all geared up for yet another PSLV mission, that would launch satellites in three different orbits for the first time.
During the mission planned for next month, PSLV will launch the 420 kg EMISAT, an Electronic Intelligence Satellite of the Defence Research Development Organisation (DRDO), along with 28 other satellites and three experimental payloads, besides demonstrating its new technology of placing them in three different orbits.
Though the workhorse launch vehicle of ISRO, has several firsts to is credit, including injecting more than 100 satellites in space and placing them in two different orbits and switching off and switching on the PS-4 in a single mission, this was for the first time the PS-4 would be brought down to lower orbits to inject the satellites in three different altitudes.
Terming its a ‘special mission’, ISRO Chairman Dr K Sivan today said a new variant of PSLV, with four strap-on motors, instead of its usual six strap-ons or the Core alone version, would be used for next month’s mission.
The PSLV would first inject the primary satellite EMISAT at an altitude of 763 km after which the rocket would be brought down to place the 28 satellites in a 504 km orbit.
Then the fourth stage rocket would be brought down further to a height of about 485 km where it would act as a payload platform for carrying out experiments using three payloads developed by Indian Institute of Space Science and Technoogy, ISRO’s own Technology demonstrator and a HAMSAT, respectively, he said.
ISRO had on 24 January successfully injected Microsat-R and Kalamsat-V2 satellites into their designated orbits using (PSLV-C44). About 13 minutes 26 seconds after lift-off, Microsat-R, an imaging satellite was successfully injected into the intended orbit of 274 km.
Subsequently, the fourth stage (PS4) of the vehicle was moved to a higher circular orbit of 453 km after two restarts, to establish an orbital platform for carrying out experiments.
Kalamsat-V2, a student payload was the first to use PS4 as an orbital platform. In the meantime, the ISRO has started preparations for the maiden mission of Small Satellite Launch Vehicle (SSLV) that would ferry two small defence satellites in the orbit, weighing about 120 kg each in July-August. Apart from the two defence satellites, the 110 tonne SSLV would also carry adaptors weighing 300 kg.