placed 31 satellites +

SRIHARIKOTA: After a lull of over four months, the Indian Space Research Organisation is back in the game as its workhorse Polar Satellite Launch Vehicle (PSLV-C40) successfully placed 31 satellites in two different orbits in one of the longest missions.The launch was also significant for another reason -- Isro demonstrated multiple-burn technology that it tested in three previous launches."This is PSLV's 40th successful launch," project director R Hutton said.PSLV-C40, in its 42nd flight,-- Cartosat-2 Series , Microsat, 28 foreign nanosatellites and an Indian nanosatellite -- in orbits. The foreign nanosatellites are from the US, France, Finland, the UK, South Korea and Canada.Around 17 minutes after the lift-off from the launch pad at Satish Dhawan Space Centre in Sriharikota at 9.28am, the rocket injected its main payload- the 710kg weighing Cartosat-2 series, the seventh satellite in the series, into a polar sun synchronous orbit at an altitude of about 510km.Within a span of around seven minutes, the rocket ejected 29 satellites as it maneuvered its way up the altitude to 519km."It is an excellent mission. Cartosat’s performance has been so far satisfactory,” said retiring Isro chairman AS Kiran Kumar after the rocket placed 30 satellites in orbit, with one remaining to be placed in a different orbit.After the ejection of the 30th satellite, the fourth stage earth storable liquid engine was restarted for the first time 30 minutes later and was shut off within five seconds. For the next nearly 45 minutes of coasting period, the rocket moved from 505km to 359km altitude before the engine was restarted again for the second time for another five seconds.Roughly around one and 45 minutes later, the rocket ejected its 31st satellite – Isro’s Microsat -- in the second orbit at an altitude of 359km. Fifteen minutes later, the engine was again ignited for the last time and shut off in 13 seconds.The PSLV-C40 mission is happening four months after the failure of PSLV-C39. PSLV-C39, which lifted off on August 31 last year, failed after the heat shield, the tip of the rocket, did not open as programmed. The satellite separated from the rocket circling in space within the closed heat shield."We are coming to the launch pad after four months. Many of our customers came ready with satellites after our previous failure. It shows their confidence in us. We have some exciting launches coming up including Chandrayaan 2, GSLV MKIII and GSLV MKII" said chairman-designate K Sivan.Satish Dhawan Space Centre director P Kunhikrishnan said the mission was an excellent tribute to chairman AS Kiran Kumar and a welcome to chairman-designate K Sivan.“Three consecutive launches are planned from second launch pad in addition to those in the first launch pad. The construction of the second assembly centre is in its final phase of completion. A project is underway to increase capability of first launch pad to 15 launches a year," said Kunhikrishnan.The main payload on Friday's launch Cartosat-2 Series satellite will provide regular remote sensing services using its panchromatic and multispectral cameras. The images sent by the satellite will be useful for cartographic applications, urban and rural applications, coastal land use and regulation, utility management like road network monitoring, water distribution, creation of land use maps, change detection to bring out geographical and man-made features and various other land information system (LIS) as well as geographical information system (GIS) applications.