India’s first geostationary satellite, APPLE, was launched on June 19, 1981, by the Indian Space Research Organisation (ISRO). It was an experimental communication satellite that was launched by the European Space Agency’s Ariane -1(V-3) rocket from Kourou, French Guiana.
APPLE was a cylindrical satellite with a diameter of 1.4 meters and a height of 1.5 meters. It weighed 670 kilograms at launch and had a design life of one year. The satellite was equipped with a dual C-band transponder that could provide both telecommunications and television broadcasting services.
APPLE was launched into a geostationary orbit at 102 degrees east longitude, over Indonesia. This means that it orbited the Earth at the same speed as the Earth’s rotation, so that it remained stationary over a single point on the surface. This made it ideal for providing communication and broadcasting services to a large area.
Here is a more detailed overview of the APPLE satellite:
| Mission | Experimental geostationary communication |
| Weight | 670 kg |
| Onboard Power | 210 Watts |
| Communication | VHF and C-band |
| Stabilization | Three axis stabilized (biased momentum) with Momentum Wheels, Torquers & Hydrazine based Reaction control system |
| Payload | C ā band transponders (Two) |
| Launch Date | June 19,1981 |
| Launch Site | Kourou (CSG), French Guyana |
| Launch Vehicle | Ariane -1(V-3) |
| Orbit | Geosynchronous (102 deg. E longitude, over Indonesia) |
| Inclination | Near zero |
| Mission life | Two years |
| Type of Satellite | Experimental |
| Manufacturer & Owner | ISRO |
| Application | Communication Experimental |
Some of the important features of APPLE:
- It was the first geostationary satellite to be launched by India.
- It was the first Indian satellite to be launched by a foreign launch vehicle.
- It carried a single C-band transponder with a power output of 20 watts.
- It was designed to operate in a geostationary orbit at an altitude of 35,786 kilometers (22,236 mi) above Earth.
- Its primary mission was to test the feasibility of using geostationary satellites for providing communication services to India.
- It was also used to conduct experiments in satellite television broadcasting and meteorological data collection.
APPLE was used for a variety of experiments, including:
- Testing the feasibility of using geostationary satellites for communication and broadcasting in India.
- Conducting experiments on satellite-based navigation and meteorological services.
- Providing television broadcasting services to remote areas of India.
APPLE was a major milestone in India’s space program and demonstrated the country’s ability to design, build, and launch its own geostationary satellites. The success of APPLE led to the development of the INSAT series of geostationary satellites, which are now used to provide a wide range of communication and broadcasting services to India and the surrounding region.
Although APPLE was only in operation for a few months, it was a significant achievement for India and ISRO. It paved the way for the development of India’s modern space program and helped to make India a leader in the field of space technology.
Some interesting facts about APPLE:
- APPLE was built by ISRO in collaboration with the French space agency CNES.
- The satellite was named APPLE by the then Prime Minister of India, Indira Gandhi.
- APPLE was the first satellite to be launched by the European Space Agency’s Ariane-1 launch vehicle.
- APPLE was used to telecast the first live television broadcast from India to the United States.
- APPLE was also used to provide telephone and data transmission services to India and its neighboring countries.
Tags: First Geostationary Satellite of India, India’s First Geostationary Satellite, India First Geostationary Satellite
