Syncom started as a 1961 NASA program for active geosynchronous communication satellites, all of which were developed and manufactured by the Space and Communications division of Hughes Aircraft Company. Syncom 2, launched in 1963, was the world's first geosynchronous communications satellite. Syncom 3, launched in 1964, was the world's first geostationary satellite.
In space mission design, a geostationary transfer orbit (GTO) or geosynchronous transfer orbit is a highly elliptical type of geocentric orbit, usually with a perigee as low as low Earth orbit (LEO) and an apogee as high as geostationary orbit (GEO). Satellites that are destined for geosynchronous orbit (GSO) or GEO are often put into a GTO as an intermediate step for reaching their final orbit. Manufacturers of launch vehicles often advertise the amount of payload the vehicle can put into GTO.
The Indian National Satellite System or INSAT, is a series of multipurpose geostationary satellites launched by the Indian Space Research Organisation (ISRO) to satisfy telecommunications, broadcasting, meteorology, and search and rescue operations. Commissioned in 1983, INSAT is the largest domestic communication system in the Indo-Pacific Region. It is a joint venture of the Department of Space, Department of Telecommunications, India Meteorological Department, All India Radio and Doordarshan. The overall coordination and management of INSAT system rests with the Secretary-level INSAT Coordination Committee.
Geosynchronous Satellite Launch Vehicle (GSLV) is a class of expendable launch systems operated by the Indian Space Research Organisation (ISRO). GSLV has been used in fifteen launches since 2001.
GSAT-3, also known as EDUSAT, was a communications satellite which was launched on 20 September 2004 by the Indian Space Research Organisation. EDUSAT is the first Indian satellite built exclusively to serve the educational sector. It is mainly intended to meet the demand for an interactive satellite-based distance education system for the country.
GSAT-2 was an experimental communication satellite built by the Indian Space Research Organisation (ISRO) and launched on one of the first GSLVs. The satellite was positioned at 48 deg east longitude in the geo-stationary orbit.
The Launch Vehicle Mark-3 or LVM3 is a three-stage medium-lift launch vehicle developed by the Indian Space Research Organisation (ISRO). Primarily designed to launch communication satellites into geostationary orbit, it is also due to launch crewed missions under the Indian Human Spaceflight Programme. LVM3 has a higher payload capacity than its predecessor, GSLV.
GSAT-4, also known as HealthSat, was an experimental communication and navigation satellite launched in April 2010 by the Indian Space Research Organisation on the maiden flight of the Geosynchronous Satellite Launch Vehicle Mk.II rocket. It failed to reach orbit after the rocket's third stage malfunctioned. The third stage was the first Indian-built cryogenic-fuelled upper stage, and was making its first flight. The ISRO suspects that the failure was caused by the third stage not igniting.
The A2100 is a model of communications satellite spacecraft made by Lockheed Martin Space Systems. It is used as the foundation for telecommunications payloads in geosynchronous orbit, as well as GOES-R weather satellites and GPS Block IIIA satellites. Over 40 satellites use the A2100 bus.
An orbital propellant depot is a cache of propellant that is placed in orbit around Earth or another body to allow spacecraft or the transfer stage of the spacecraft to be fueled in space. It is one of the types of space resource depots that have been proposed for enabling infrastructure-based space exploration. Many depot concepts exist depending on the type of fuel to be supplied, location, or type of depot which may also include a propellant tanker that delivers a single load to a spacecraft at a specified orbital location and then departs. In-space fuel depots are not necessarily located near or at a space station.
GSAT-5P, or GSAT-5 Prime, was an Indian communications satellite which was lost in a launch failure in December 2010. Part of the Indian National Satellite System, it was intended to operate in geosynchronous orbit as a replacement for INSAT-3E.
Space Infrastructure Servicing (SIS) is a spacecraft concept being developed by Canadian aerospace firm MDA to operate as a small-scale in-space refueling depot for communication satellites in geosynchronous orbit.
INSAT-4CR was a communications satellite operated by ISRO as part of the Indian National Satellite System. Launched in September 2007, it replaced the INSAT-4C satellite which had been lost in a launch failure the previous year. The satellite was initially stationed in geostationary orbit at a longitude of 74 degrees east, with expected operational life of at least ten years, however this may have been reduced by the underperformance of the Geosynchronous Satellite Launch Vehicle which placed it into orbit. INSAT-4CR is planned to be replaced by GSAT-31, which was launched on February 6, 2019.
GSAT-14 is an Indian communications satellite launched in January 2014. It replaced the GSAT-3 satellite, which was launched in 2004. GSAT-14 was launched by a Geosynchronous Satellite Launch Vehicle Mk.II, which incorporated an Indian-built cryogenic engine on the third stage.
INSAT-4E, also known as GSAT-6, is a member of the INSAT family and is a multimedia communication satellite that will offer a Satellite Digital Multimedia Broadcasting (S-DMB) service across several digital multimedia terminals or consoles which can be used to provide information services to vehicles on the fly and to the mobile phones. The satellite can be used for other social and strategic applications.
GSAT-7 or INSAT-4F is a multi-band military communications satellite developed by the Indian Space Research Organisation. The Indian Navy is the user of the multi-band communication spacecraft, which has been operational since September 2013. According to defense experts, the satellite will enable the navy to extend its blue water capabilities and stop relying on foreign satellites like Inmarsat, which provide communication services to its ships.
Superbird-A2, known as Superbird-6 before launch, was a geostationary communications satellite ordered and operated by Space Communications Corporation (SCC) that was designed and manufactured by Hughes on the BSS-601 satellite bus. It had a mixed Ku-band and Ka-band payload and was expected replace Superbird-A at the position at 158° East longitude. It was expected to provided television signals and business communications services throughout Japan, South Asia, East Asia, and Hawaii.
GSAT-6A was a communication satellite launched by the Indian Space Research Organisation (ISRO). It featured a 6-metre (20 ft) unfurlable S-band antenna similar to the one used on GSAT-6. Around 17 minutes after lift-off, the three stage GSLV Mk.II rocket flying on GSLV F08 mission successfully injected the satellite into a geosynchronous transfer orbit. Due to power failure during its orbit raising burns the communication was lost with GSAT-6A before it could reach its final circular geostationary orbit (GSO).
GSAT-29 is a high-throughput communication satellite developed by the Indian Space Research Organisation (ISRO). The mission aims at providing high-speed bandwidth to Village Resource Centres (VRC) in rural areas. The two Ku and Ka operational payloads will provide communication services to Jammu and Kashmir and Northeast India under Digital India programme. At the time of launch GSAT-29 was the heaviest satellite, weighing 3,423 kg (7,546 lb), that was placed in orbit by an Indian launch vehicle. Approved cost of GSAT-29 is ₹175.63 crore (US$20 million).
