Simulated lunar craters created in Chitradurga to plan lander’s descent

The Indian Space Research Organsiation started a series of ground and aerial tests linked to the critical Moon landing of Chandrayaan-2 on Friday, at its new site at Challakere in Chitradurga district, 400 km from Bengaluru.

ISRO Satellite Centre or ISAC, the lead centre for the second Moon mission, has artificially created close to ten craters to simulate the lunar terrain and test the Lander’s sensors.

A small ISRO aircraft has been carrying equipment with sensors over these craters to plan the tasks ahead.

ISRO, along with a host of other scientific and strategic agencies, owns vast land for its future missions at Challakere, in a ‘Science City.’

ISAC Director M.Annadurai told The Hindu, “The campaign for the Lander tests of Chandrayaan-2 has started. Tests are conducted over the simulated craters at Chitradurga. We are using an aircraft to assess whether the sensors on the Lander will do their job [later] of identifying the landing spot on the Moon.”

Chandrayaan-2 is tentatively set for late 2017 or early 2018 and includes soft-landing on Moon and moving a rover on its surface.

Landing on an alien surface is very complicated, said Dr. Annadurai, who was also the Project Director for the successful Chandrayaan-1 lunar exploration mission of 2008. The Lander’s success hinges on sensors. As it descends from the mother ship or Orbiter, they must correctly judge the distance to the lunar surface, the required speed and the time to hover over the location, for a few seconds. The terrain should enable a smooth landing and steady movement of the Rover when it is released from the Lander.

In the coming months up to March, ISAC would conduct many tests: on avionics and electronics; testing the Lander’s legs; and its eight throttlable engines, followed by a combined full test, at Bengaluru and Chitradurga.

The mission includes an Orbiter, a Lander and a Rover, all being readied at ISAC in Bengaluru. The Orbiter spacecraft when launched from Sriharikota will travel to the Moon and release the Lander, which will in turn deploy a tiny Rover to roam the lunar surface - all three sending data and pictures to Earth.

Last week, the European Space Agency’s Mars lander, the Schiaparelli craft, crashed while parachuting to the Martian surface. Asked what lessons could be drawn from this, Dr. Annadurai said they were different in nature. The Chandrayaan-2 Lander does not use parachutes; the configurations and gravity issues of the two missions are different. “It still calls for a good amount of testing” for Chandrayaan-2, he said.