Telecom satellite GSAT-15 launched

The 3,164-kg spacecraft will replace the ageing Insat-3A and 4B spacecraft that are in the same orbital slot when they expire. 

GSAT-15, the nation's newest communications satellite, was launched in the wee hours of Wednesday from Kourou in French Guiana in South America.

The 3,164-kg spacecraft will replace the ageing Insat-3A and 4B spacecraft that are in the same orbital slot when they expire.

Its 24 transponders in the Ku-band will mainly cater to public and private direct-to-home broadcasters besides VSAT operators. (A majority of private operators use capacity leased on foreign spacecraft).

GSAT-15's lone GPS-augmentation or GAGAN transponder in the L1 and L5 bands will ensure back up for GPS-based satellite navigation across the region.

The Indian Space Research organisation said GSAT-15 was put into space at 3.04 a.m. IST by the European launch vehicle Ariane VA-227; it had Arabsat-6B as a co-passenger. The initial elliptical orbit of 250 km x 35,819 km, inclined at an angle of 3.9 degrees to the Equator, "was very close to the intended one," ISRO said.

The Master Control Facility that handles post-launch communications satellites at Hassan in Karnataka took over the command and control of GSAT-15 immediately after it was ejected into space. "Preliminary health checks of the satellite revealed its normal health," it said.

In the coming days, the MCF team will raise or correct the orbit gradually into a circular one of 24-hour period and stationed at 36,000 km from ground. Its key systems will be switched on in steps, tested and made operational once it is slotted over the country at 93.5 degrees East longitude.

GSAT-15, including the fee to European launch company Arianespace, has cost over Rs. 850 crore.