GSAT-8 is a high-power Indian communication satellite launched by Ariane 5 from Kourou in May 2011. Besides 24 Ku-band transponders, it carries a payload for GAGAN, India's GPS correction service.
GSAT-8 has 24 high-power Ku-band transponders that add capacity to the INSAT system.
It also carries a two-channel GAGAN payload working in the L1 and L5 bands. A network of ground receivers measures GPS errors over India, and the corrections are broadcast through geostationary satellites like GSAT-8. Receivers that use them get more accurate positions.
GSAT-8 weighed 3,093 kg at launch, of which 1,426 kg was dry mass. Its solar arrays give 6,242 W and it has three lithium-ion batteries. It is built on ISRO's I-3K bus and was designed to work for more than 12 years.
An Ariane 5 rocket (flight VA202) launched GSAT-8 from Kourou in French Guiana in May 2011, together with the ST-2 satellite. The satellite then used its own 440 N liquid apogee motor to climb to geostationary orbit. ISRO lists its position as 55° E.
The public satellite catalogue still carries GSAT-8 with an operational flag. That flag is not confirmation from ISRO that the satellite is still in service, so treat its current status as unconfirmed.