Deep space network to track India's lunar mission (Lead)

Dec 15, 2007, 14:10 GMT

Bangalore, Dec 15 (IANS) The Indian space agency is bracing up for its first lunar exploration mission Chandrayaan-1 due April next year by setting up a deep space network (DSN) near this IT hub.

The network, coming up at Byalalu, about 45 km from here, and comprising mainly two powerful dish antennas of 32-metre and 18-metre diameter, will keep track of the unmanned moon mission and provide command support during its two-year orbit around earth's only natural satellite.

The first lunar mission, estimated to cost about Rs 3.9 billion at revised estimates, will be launched by the Indian Space Research Organisation (ISRO) from its Satish Dhawan Space Centre at Sriharikota in Andhra Pradesh, using the indigenous polar satellite launch vehicle (PSLV).

'The DSN will be used to send commands and receive telemetry signals, including massive scientific data from the spacecraft, while orbiting around moon at a whopping distance of 385,000 km away from earth at an altitude of 100km from the lunar surface,' ISRO Telemetry Tracking and Command Network (ISTRAC) director S.K. Shivakumar told reporters on a visit to the facility Saturday.

'The DSN, installed at an upfront cost of Rs.1 billion in this 135-acre campus, will be the base station for not only lunar missions Chandrayaan-I & II, but also for our future planetary exploration missions like Mars, which is about 60-million km away,' he said.

As the first and only one of its kind in the subcontinent, the network will provide the space agency the capability to handle deep space missions India plans to undertake in future and provide cross-support to other deep space missions of international space agencies because of its inter-operable features and world standards specifications.

'The station is capable of performing telemetry, tracking and command operations in S-band and science data reception in X-band. The 32-metre antenna's reflector is a shaped parabola and the Cassegrain feed system consists of corrugated forms, seven mirrors beam wave-guide system and shaped hyperbolic sub-reflector.

'Cryo cooled low noise amplifiers help in realising very low system noise temperatures and high figure of merit for the ground station. Very high power uplinking capability up to 20kw in S-band enables the station to send commands to the spacecraft in lunar orbit and beyond,' Shivakumar pointed out.

Before ISRO embarks on deep space exploration in the next decade, the network will track its proposed Astrosat, a space telescope designed to scout for galactic clusters, new stars beyond the Milky Way and a variety of cosmological phenomenon.

The indigenously built network has another 18-metre dish antenna, designed and fabricated by Vertex RSI of Germany.

State-owned Electronics Corporation of India Ltd (ECIL), Bhabha Atomic Research Centre (BARC) and 38 leading manufacturing firms such as L&T and Godrej & Boyce in the private sector were roped in to set up the massive network, including the 60-tonne dish antenna.

'ECIL has designed and developed the 180-degree panel reflector for the 32-metre antenna, which cost us Rs.600 million. The command station includes a spacecraft control centre, a space science data centre and an international ground station augmentation.

'All systems connected with the lunar mission are being tested in the run-up to the launch, which has been tentatively fixed for April 9, 2008,' Shivakumar said.

The Indian DSN is the only one between European Space Agency's antenna located at Madrid in Spain and National Aeronautical and Space Administration's antenna at Perth in Australia.

© 2007 Indo-Asian News Service