September 9 will be a historic day with the Indian Space Research Organisation (Isro) taking up its 100th mission — the launch of the Polar Satellite Launch Vehicle (PSLV-C21) from Sriharikota in Andhra Pradesh.
The space agency has undertaken 99 missions, including 62 satellites and 37 launch vehicles, since the launch of the Aryabhatta in 1975. “PSLV-C21 will be our 100th mission, and it is likely to be launched on September 9. It will be a momentous occasion for the country. This launch will essentially be for commercial purposes,” an Isro official said.
SPOT-6, an advanced French remote-sensing satellite built by ASTRIUM SAS, will be launched on board the PSLV-C21. Besides the 720-kg satellite, the launch vehicle will also carry Proiteres, a 15-kg Japanese spacecraft.
“The objective of the Isro is to develop space technology, and use it for various national tasks. With the initiation of various kinds of space missions, considerable expertise has been generated. Scientists are now coming up with proposals for new missions,” the official said.
The PSLV is capable of launching satellites weighing 1,600 kg in the 620-km sun-synchronous polar orbit, and those weighing 1,050 kg in the geo-synchronous transfer orbit. It stands at a height of 44.4 metres and has lift-off weight of 295 tonnes. With a mechanism constituting four stages, the launch vehicle uses solid and liquid propulsion systems alternately. The first stage, powered by one of the largest solid propellant boosters in the world, carries 139 tonnes of propellant. A cluster of six strap-ons are attached to the first-stage motor, four of which are ignited on the ground and two in the air.
Till April, there have been 20 successful PSLV flights in a row. After its 100th mission, Isro is likely to launch the 3,400-kg communication satellite GSAT-10 on any date between September 21 and 23 by European space consortium Arianespace's Ariane-5 rocket from Kourou in French Guiana.