GSLV-12 Launch

GSAT-12 Launch

India notched another milestone in its space programme by successfully launching a heavy-duty rocket that placed a major communications satellite in space.

The PSLV blasted off successfully carrying the 1,410 kg GSAT-12 satellite from the spaceport. The satellite has a life span of about seven years.

With this, India added 12 more communication transponders to its space-based network.

The launch took place under a cloudy sky, with the Rs.95 crore rocket PSLV-C17 – measuring 44 metres in height and weighing 320 tonnes – soaring off into space with a roar.

It ferried the Rs.105 crore GSAT-12 having 12 extended C-band transponders – automatic receivers and transmitters for communication and broadcast of signals.

People perched atop of the nearby buildings too happily applauded as PSLV-C17 went up.

The GTO is an intermediate orbit from where normally communication satellites will be moved to its final geosynchronous orbit by firing the on-board motors.

The rocket’s navigation systems were powered by Indian-made advanced Vikram processors.

The GSAT-12 carries around 851 kg of fuel on-board to fire the motors. (A geosynchronous orbit is one directly above the earths’ equator. For an observer from the earth a satellite in geosynchronous orbit will seem motionless, stationary at one point in the sky).

The rocket placed the satellite in sub GTO with a 284 km perigee (nearest point to earth) and 22,020 km apogee (farthest point from the earth). The satellite was raised to 36,000 km apogee from 22,020 km.

The satellite will be useful for various communication services like tele-education, tele-medicine and for village resource centre.

The GSAT-12 satellite is also expected to serve the Very Small Aperture Terminal (V-SAT) sector. VSATs are used to transmit data like point of sale transactions or to provide satellite internet access.

The satellite will augment transponder capacity of Indian National Satellite (Insat) system which at present comprises of eight satellites — Insat-2E, Insat-3A, Insat-3C, Insat-3E, Insat-4A, Insat-4B (working at 50 percent capacity) Insat-4CR and GSAT-8 providing 175 transponders in the S, C, extend C and Ku bands.

The Indian space agency has leased 86 more transponders from various foreign satellites. It is estimated there is an unmet demand for 170 transponders.

ISRO used its third PSLV rocket variant – PSLV-XL – with longer strap-on motors with higher fuel capacity – to put the latest communication satellite in the space.

The other two rocket variants are the PSLV standard with 11.3 metres six strap-on motors and the PSLV Core Alone (CA) rocket without the six strap-on motors.

This is the second time ISRO has launched a rocket with this specification. The earlier one was for the Chandrayaan moon mission.

This is also only the second time ISRO is using a PSLV rocket for launching a satellite to be finally placed in geostationary orbit. The first satellite was Kalpana-1 (originally named as Metsat), a meteorological satellite launched in 2002.

The PSLV has an excellent success record since 1994, launching many Indian and foreign satellites.

ISRO planned to launch remote sensing satellite – Megha-Tropiques later this year.