PSLV-C18 ROCKET LAUNCH SIGNIFICANCE An Indo-French satellite Megha-Tropiques was successfully placed in orbit by PSLV-C18 (44 meters tall and weight 230 tones) rocket in a perfect launch from Satish Dhawan Space Centre as part of a key mission that will help understand global tropical weather. The four satellites were injected into orbit one after another in clockwork precision about 26 minutes after PSLV lifted off in a plume of smoke. The mission described as a "grand success" by ISRO Chairman K Radhakrishnan. "PSLV-C18 has been a grand success. Very precisely, four satellites were injected in space orbit and the difference between what we planned and what we achieved is just two km over an altitude of 867 km," he told scientists after the launch. Satellites: There are four satellites launched through PSLV-C18, Megha-Tropiques a 1000-kg satellite and three smaller satellites the 10.9 kg SRMSAT built by the students of SRM University near Chennai, the three kg remote sensing satellite Jugnu from the Indian Institute of Technology-Kanpur and the 28.7 kg VesselSat from LuxSpace of Luxembourg to locate ships on high seas. Significance of Megha-Tropiques: Megha-Tropiques carries four payloads SAPHIR, SCARAB and a complementary scientific instrument GPS-ROS by French space agency CNES (Centre National d'Etudes Spatiales) and MADRAS jointly by ISRO and CNES. Megha-Tropiques (Megha meaning cloud in Sanskrit and Tropiques denoting tropics in French) will investigate the contribution of energy exchanges in the tropics to climate dynamics. The satellite will provide scientific data on contribution of the water cycle to the tropical atmosphere with information on condensed water in clouds, water vapour in the atmosphere, precipitation and evaporation. According to ISRO, Megha-Tropiques with its circular orbit inclined 20 degree to the equator will enable climate research and also aid scientists seeking to refine weather prediction models. India is the second nation in the world to launch such a space mission. Earlier one was The Tropical Rainfall Measuring Mission (TRMM) a joint mission of NASA and the Japan Aerospace Exploration Agency (JAXA) designed to monitor and study tropical rainfall was launched Nov 27, 1997. Information beamed by Megha-Tropiques is expected to benefit not only India, but also all countries in the Indian Ocean region and other parts of the world. ISRO has built the satellite at a cost of Rs 80 crore with "equal contribution" from CNES. The PSLV rocket crosses the 50 satellite launch milestone since 1993 with the 19th consecutive successful launch.