Lunar lander ready to be tested

Flush with the success of the PSLV- C37 mission which set a world record by placing 104 satellites in orbit, the Indian Space Research Organisation (ISRO) is turning its attention to India’s second lunar mission, Chandrayaan- 2, scheduled for 2018.

The static test of the lander module of Chandrayaan- 2 will be held at the ISRO Propulsion Complex, Mahendragiri, by the end of February.

Director, Liquid Propulsion Systems Centre (LPSC), S. Somanath, told The Hindu that the test would measure the performance of the propulsion system of the lander module.

The Chandrayaan-2 craft consists of an orbiter, lander and rover to be launched as a composite stack into the earth parking orbit by a GSLV Mark 2 rocket. The orbiter later carries the combined stack upto the lunar orbit where the lander separates to make a soft landing on the moon’s surface and deploy the rover.

In contrast, the Chandrayaan-1 mission comprised only an orbiter and moon impact probe.

Challenges in soft landing

Mr.Somanath said the soft landing involved in the Chandrayaan- 2 mission required special propulsion and control systems and complex electronics. The lander would have four engines to make a controlled descent from the orbiter.

For the static test, the craft would be mounted on a frame and the four engines fired at varying thrust.

A month later, another lander module, a replica of the first one, would be tested in a suspended state. The craft would be hung from a crane and the engines fired to move the module in different directions and simulate a soft landing.

According to the ISRO website, the scientific payloads on board the orbiter, lander and rover of the Chandrayaan- 2 mission are expected to perform mineralogical and elemental studies of the lunar surface.

In 2010, it was agreed that the Russian space agency Roscosmos would develop the lunar lander while the ISRO would be responsible for the orbiter and rover as well as the launch by GSLV.

But with Roscosmos seeking more time to fulfil its commitment, ISRO took up the development of the lunar lander, turning Chandryaan-2 into a totally indigenous project.

Cryogenic engine

Meanwhile, the stage is set for the second ground test of the cryogenic upper stage of GSLV Mark 3, India's heaviest launch vehicle, at Mahendragiri on Friday. Designed and developed by the LPSC, the C- 25 engine which uses liquid oxygen and liquid hydrogen for propulsion will be fired for 640 seconds during the test.

In January this year, the cryogenic stage was successfully tested for a duration of 50 seconds.