GSAT-29 Satellite Launched

• 15 Nov 2018

The Indian Space and Research Organisation (ISRO) has successfully launched GSAT-29 (Geostationary Satellite) communication satellite through Geosynchronous Satellite Launch Vehicle Mark III (GSLV Mk III).

• GSLV Mk III successfully placed the satellite in Geosynchronous Transfer Orbit (GTO) after three orbit-raising maneuvers, the satellite will be placed in the Geostationary Orbit.

Payloads on GSLV Mk III

• GSAT-29, weighing 3,423kg, is the heaviest satellite to be put into orbit by ISRO’s launch vehicle and is designed for a mission life of 10 years.
• It is a multiband, multi-beam communication satellite which will serve as a testbed for several new and critical technologies.
• Its Payload also consists of Geo High-Resolution Camera and an Optical Communication Payload.

Significance

• GSAT-29 will help in providing internet connectivity in remote areas especially in Jammu & Kashmir and North-Eastern regions of India.
• Geo-High Resolution Camera will help in high-resolution imaging and help in surveillance in the Indian Ocean.
• Optical Communication payload will help in data transmission at a very high rate through the optical communication link.
• The successful launch signifies the completion of the experimental phase of GSLV Mk III and it is now operational.
• Future Mission of ISRO, Chandrayaan-2 and Gaganyaan missions (human space flight) will also be launched by GSLV Mk III.
• The success of GSLV Mk III marks an important milestone in the Indian space programme towards achieving self-reliance in launching heavier satellites.

Types of Orbits

In general, there are two types of orbits:

• Polar Synchronous
• Geosynchronous

Polar Orbit

• A polar orbit travels north-south over the poles and takes approximately 90 minutes for a full rotation.
• These orbits have an inclination near 90 degrees. This allows the satellite to see virtually every part of the Earth as the Earth rotates underneath it.
• These satellites have many uses such as monitoring crops, global security, measuring ozone concentrations in the stratosphere or measuring temperatures in the atmosphere.
• Almost all the satellites that are in a polar orbit are at lower altitudes.
• An orbit is called sun-synchronous when the angle between the line joining the center of the Earth and the satellite and the Sun is constant throughout the orbit.
• These orbits are also referred to as “Low Earth Orbit (LEO)” which enables the onboard camera to take images of the earth under the same sun-illumination conditions during each of the repeated visits, thus making the satellite useful for earth resources monitoring.
• It passes over any given point on Earth’s surface at the same local solar time.

Geosynchronous Orbit

• Geosynchronous satellites are launched into orbit in the same direction the Earth is spinning and can have any inclination.
• When the satellite is in orbit at a specific altitude (approximately 36,000km above the Earth's surface), it will exactly match the rotation of the Earth.
• While, Geostationary orbits fall in the same category as geosynchronous orbits, but with that one special quality of being parked over the equator.
• In the case of geostationary satellites, the Earth’s force of gravity is exactly enough to provide acceleration required for circular motion.
• Geosynchronous Transfer Orbit(GTO): To attain geostationary or geosynchronous earth orbits, a spacecraft is first launched into a Geosynchronous Transfer Orbit.
• From the GTO the spacecraft uses its engines to shift to geostationary or geosynchronous orbit.