S Satish, Director (Public Relations), Indian Space Research Organisation (ISRO), said: “As of now, the spacecraft will be launched at 6.20 am on October 22. Today, at 5 am we started filling the second and fourth stage of the launch vehicle, PSLV-C11, which will use the liquid propulsion system weighing about 44 tonnes.”

The filling process will take about 35 hours and is expected to finish by 4 pm tomorrow, said Satish.

Earlier in the day, Prof J N Goswami, director of the Physical Research Laboratory (PRL), Ahmedabad, who is also the principal scientist for the Chandrayaan-1 mission, spoke about the possibility of finding helium-3 on the lunar surface. “Although generating power through nuclear fusion of helium-3 is a distant dream, but the possibilities are immense,” he said. The samples brought to Earth by the Apollo mission have indicated that Iron titanium oxide traps helium-3 molecules on the lunar surface, he said.

Goswami said he-3 content is very low. For every 100,000 helium-4 molecules, there is only one helium-3 molecule on the lunar surface. Besides, the scientific community is yet to simulate the conditions necessary for nuclear fusion. But, if Chandrayaan-1 is able to locate probable areas for finding helium-3, that in itself will be a very big achievement. It will help eliminate the two stages of producing deuterium from hydrogen and then producing helium-3 from deuterium, he added.

Goswami also elaborated PRL's contribution to India's first lunar mission. Along with realising the payload for the High Energy X-ray Spectrometer (HEX) designed and developed jointly by PRL and ISRO's Satellite Centre at Bangalore, PRL is also the nodal centre for ISRO's Planetary Science and Exploration (PLANEX) programme. PLANEX aims for technological advancement in planetary research and is formulating ISRO’s future planetary exploration programmes by evaluating proposals for possible Chandrayaan-2 payloads.

Emphasising the aims and objectives of HEX, Goswami said: “The most futuristic dream of science is to set up a human-cum-robotic base on the lunar surface and HEX will pave the way for it.” He said the polar region on the moon is the most plausible site for this because of the simultaneous presence of mountains receiving perennial solar energy, and permanently shadowed areas with temperature much below zero degree, which act like deep freezers for water-ice. So, HEX, along with NASA's Mini-SAR, will try to identify the polar regions covered with thick water-ice deposits, he said.