Countdown begins for PSLV-C35/SCATSAT-1 mission on Sept 26

CHENNAI  : The 48 and half hour countdown for the launch of PSLV-C35/SCATSAT-1 Mission began at 0842 hrs at the Satish Dhawan Space Centre at the spaceport of Sriharikota, about 80 km from here, today.
The four-stage home grown rocket, in its 37th flight, carrying the 371 kg SCATSAT-1 for weather related studies and seven other satellites, which would ride as piggyback, would lift off from the First Launch Pad at 0902 hrs on September 26.
This mission was unique for the Indian Space Research Organisation (ISRO) as for the first time, it would place the satellites in two different orbits, after switching off and re-igniting the fourth stage engine two times more than one hour after the lift off and injection of SCATSAT-1.
Almost about two hours after the flight, the remaining seven co-passenger satellites, together weighing about 304 kg, would be injected into the orbit.
ISRO sources said Mission Readiness Review (MRR) Committee and the Launch Authorisation Board (LAB) have cleared the countdown of PSLV-35/SCATSAT-1 Mission.
During the countdown, which has been progressing smoothly, propellant filling operations would be carried out.
This would be the 15th flight of PSLV in ‘XL’ configuration.
ISRO sources said the co-passenger satellites were from Algeria, Canada and the USA as well as two satellites from Indian University/Academic Institute. The total weight of all the eight satellites was about 675 kg.
Of the eight satellites, the SCATSAT-1 would be launched into a 730 km Polar Sun Synchronous Orbit (SSO) inclined at an angle of 98.1 deg to the equator, whereas the two Indian University/Academic Institute satelites and the five foreign satellites would be placed in a689 km Polar orbit of 98.21 degree inclination later.
This is the first mission of PSLV, which has 35 successive successful launches, would be launching its payloads in two different orbits.
About 16 minutes after the lift off, the fourth stage of the rocket would be cut off and about 30 to 40 seconds later, the SCATSAT would get separated and injected into the orbit.
The fourth stage will be restarted and cut off about one hour and 22 minutes after the blast off twice and after two hours and eleven minutes into the flight, the fourth stage will be restarted and then in a span of four minutes all the remaining seven satellites would be injeced into the intended orbit.
The switching off and switching on of the rocket’s fourth stage termed as multiple burn technology and it was first tested by ISRO in one of its PSLV mission in December last year.
(AGENCIES)