New Delhi: The 20-hour countdown for India’s ambitious lunar mission Chandrayaan-2 began at 6:51 AM on Sunday and the launch is set for Monday 2:51 AM.

The 640-tonne rocket Geosynchronous Satellite Launch Vehicle-Mark III (GSLV-Mk III) standing at about 44 metre tall, is nicknamed the ‘Bahubali’, as like the hero in the successful film lifts a heavy Lingam, the rocket will carry the 3.8-tonne Chandrayaan-2 spacecraft.

About 16-minutes into its flight, the GSLV-Mk III rocket is expected to sling the Rs 603 crore Chandrayaan-2 into an Earth parking 170×40400 km orbit.

From there, it will be a long journey for the Chandrayaan-2 spacecraft carrying lander-Vikram and rover-Pragyaan will travel further to the moon.

On September 6, the Lander Vikram is expected to make a soft landing on the moon and then Pragyaan will roll out to carry out in-situ experiments.

Meanwhile, Indian Space Research Organisation (ISRO) Chairman K Sivan on Saturday prayed at Tirumala temple here for the success of second moon mission Chandrayaan-2.

Speaking to media outside, the ISRO Chairman said preparations for the mission were going on without any hitch. He said the mission was expected to bring forth lot of information and revelations in the field of lunar science. He said the mission would demonstrate new technology of soft landing.