13.10.11

PSLV - C18 launched



The Indian Space Research Organisation on Wednesday used a strategic delay to evade a possible encounter with space debris and ensured a perfect launch of the PSLV-C18. Lifting off from the Sriharikota spaceport at 11.01 am, a minute after its designated time, Isro’s workhorse PSLV put in orbit three satellites, including the Indo-French Megha-Tropiques. With this, the PSLV, which was inducted in 1993, exceeded a half century of satellite launches. “The launch was a great success. We had targeted a circular orbit of 867 km for weather satellite Megha-Tropiques and we have achieved, as per initial reports, 865 km,” said Isro chairman K Radhakrishnan. “It demonstrates again the reliability and versatility of PSLV as a launch platform.” After beginning the 50-hour countdown at 9 am on Monday, Isro got wind of the space debris. Three hours before the schedule lift-off time, it found that the probability of collision remained high. “We delayed the launch by a minute as there was a higher probability of the launch vehicle hitting space debris at an altitude between 600 km and 800 km,” an official said. One minute is a significant amount of time in this context as any object in space at that height moves at 8 km/ second. The delay ensured that the rocket reached the altitude after the debris had moved away by about 500 km and the satellites could be safely ejected into the orbit. The 1,000kg Megha-Tropiques, put in orbit 22-and-a-half minutes after the rocket lifted off, was jointly developed by Isro and French national space agency CNES. It will study the water cycle and energy exchanges in the tropics. Its circular orbit is inclined at 20 degrees to the equator allowing it to cover more area on both sides of the equator. “It will help us understand our climate better. This knowledge will also help our farmers,” said Radhakrishnan. It is only the second satellite of its kind in the world. The first, Tropical Rainfall Measuring Mission (TRMM) developed jointly by the US and Japan, was launched in 1997. “Megha-Tropiques, part of a global precipitation measuring mission, can be considered the contribution of India and France to the project.” The other satellites are the 28.7kg VesselSat-1 of Luxembourg, 3kg Jugnu of IIT Kanpur and 10.9-kg SRMSat of SRM University in Chennai.

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