Less than an hour before liftoff, India’s second mission to moon, Chandrayaan-2 onboard GSLV Mk-III M1, was called off on July 15 due to a technical snag, ISRO said.

The countdown to the launch scheduled for 2.51 am was stopped 56 minutes and 24 seconds before liftoff at 1.55 am following the announcement from mission control centre.

Confusion prevailed for several minutes before ISRO came out with an official confirmation about the launch being cancelled.

“A technical snag was observed in the launch vehicle system at t-minus 56 minutes. As a measure of abundant precaution, Chandrayaan-2 launch has been called off,” said ISRO associate director (public relations) B.R. Guruprasad. “The revised launch date will be announced later,” he added.

Another ISRO official said: “It is not possible to make the launch within the (launch) window. (A new) launch schedule will be announced later.”

ISRO had earlier scheduled the launch in the first week of January, but shifted it to July 15.

The liftoff of the three-component spacecraft weighing 3,850 kg and comprising an orbiter, lander and rover was scheduled from the Satish Dhawan Space Centre in Sriharikota.

Chandrayaan-2 was supposed to explore the uncharted lunar south pole, 11 years after ISRO’s successful first lunar mission Chandrayaan-1, which made more than 3,400 orbits around the moon and was operational for 312 days till August 29, 2009.

The Rs 978 crore Chandrayaan-2 onboard the heavy-lift rocket Geosynchronous Launch Vehicle GSLV Mk-III-M1 would have taken 54 days to accomplish the task of landing on the moon through meticulously planned orbital phases.

After a full dress rehearsal last week, the countdown for the mission commenced at 6.51 am on July 14 and scientists had undergone various stages of propellant filling to power the rocket ahead of the launch.

Chandrayaan-2 has 13 payloads in total with eight of them in the orbiter, three payloads in Vikram and two in Pragyan. Five payloads are from India, three from Europe, two from the US and one from Bulgaria.

A Laser Retroreflector Array (LRA) of NASA is among the payloads and is aimed at understanding the dynamics of Earth’s moon system and deriving clues on lunar interior.

Through Chandrayaan-2, in which home-grown technology is deployed, scientists aim to expand India’s footprint in space, shed light on unexplored section of moon - the south pole region, enhance knowledge about space, stimulate advancement of technology and promote global alliances.

But why the south polar region of the moon?

According to ISRO, the lunar south pole is an interesting surface area that remains in the shadow compared to the north pole. There is a possibility of water present in permanently shadowed areas around it, it said, adding craters in the south pole region have cold traps and contain fossil record of the early solar system.

The lander Vikram - named after the father of Indian space research programme Vikram Sarabhai - carrying the rover Pragyan will be landed in a high plain between two craters at a latitude of about 70 degrees south of the moon.

Then the 27-kg Pragyan and a six-wheeled robotic vehicle will set out on its job of collecting information on the lunar surface.

The rover can travel up to 500 m, leveraging solar energy and both Pragyan and Vikram have a mission life of one lunar day, which approximately equals 14 Earth days.

ISRO officials said the challenges involved in the moon landing were identifying trajectory accurately; taking up deep space communication; trans lunar injection, orbiting around the moon, taking up soft landing on the moon surface and facing extreme temperatures and vacuum.

A safe site free of hazards for landing would be decided based on pictures sent back by the camera onboard the lander and after touchdown the rover will carry out experiments for 14 Earth days.

Billed as the most complex and prestigious mission ever undertaken by ISRO since its inception, Chandrayaan-2 would make India the fourth country to soft land a rover on the lunar surface after Russia, the US and China.