Deep Space Networks

Sending a satellite to the Moon is only one part of the story, and the other part is to establish a deep space network for tracking and communicating with the satellite when it is in lunar orbit.

China does not have an exclusive network to cater for their Moon mission. There are few networks available globally like the US network—consisting of sites in California, Australia and Spain. However, geopolitics plays a dominant role in this, and in case of China, this network is off limits for political reasons. So the mission relied on a combination of Chinese and European assets. European Space Agency (ESA) has offered China assistance with communications and tracking relays to

and from the probe using its deep space network ESTRACK. This support was mainly because the Chinese had promised to share the data gathered from the Chang’e-1 mission in return [10]. China has wisely avoided any overdependence on such agencies. For purpose of the Moon mission, they have modified their S-band aerospace Telemetry, Tracking and Command (TT & C) network designed earlier for their manned space programme. The largest antennas for this network have an aperture of only 12 m. A series of technical measures were taken to ensure that such antennas could communicate with their Moon probe too [11].

India has installed a pair of giant antennas to monitor its Moon mission. The facility known as Indian Deep Space Network (IDSN) consists of two powerful dish antennas, 32 and 18 m in diameter. This network will serve as the base station for future planetary missions like to Mars and would also be used to track the proposed space telescope, the astronomical satellite (Astrosat).[243] Apart from this, various ground stations within and outside India are available under the ISRO Telemetry, Tracking and Command Network (ISTRAC) for providing ground support to Moon missions.

As per JAXA official website for the purposes of Kaguya mission, Japan is making use of the terrestrial station which is present at many places of the world, with Sagamihara in Japan as a centre. The deep space centre at Usuda and Uchinoura Space Center that operates two large antennas (20- and 34-m dishes) also form part of this telemetry tracking and command network.