Bangalore: An ambitious and confident Indian Space Research Organisation (ISRO) is not only planning deeper forays into space, starting with Mars, but also looking at the complications involved in setting up a lunar base.

"There are three possible time slots to send a Mars mission - in 2013, 2016 and 2018," ISRO chief Dr K Radhakrishnan said Wednesday in Bangalore. "We will be looking at 2016 or 2018."

According to Dr Radhakrishnan, ISRO would utilise either of its launch vehicles – the Polar Satellite Launch Vehicle (PSLV) or the Geosynchronous Satellite Launch Vehicle (GSLV) - to send a satellite into Martian orbit. "It can be done in four or five years, but the challenge is to define what scientific experiments we would conduct there," he said.

Former ISRO chairman, Madhavan Nair, said Chandrayaan-1's discovery of the presence of water near the lunar poles had increased the chances of building the lunar base. "It is going to be the frontier for exploration of the universe," he said.

According to Nair, analysis of data obtained last year from scientific instruments onboard the Chandrayaan-1 indicated water molecules on the moon. The presence of Hydroxyls - a molecule comprising an oxygen atom and a hydrogen atom - in lunar soil was also promising in this regard.

Offering a contrarian sentiment was former ISRO chairman, Prof UR Rao, who wasn't too sure if establishing a colony on the moon was a good idea. However, he said, the moon was a rich source of Helium-3, a fuel for nuclear fusion, which one day could make the earth energy sufficient for thousands of years.

However, Rao held out a glimmer of hope for lunar colonies pointing out that the Japanese lunar mission, Kaguya's, recent discovery of underground tunnels on the lunar surface offered increased hope for human colonies.

The Japanese Aerospace Exploration Agency announced the discovery of skylight-like deep holes on moon which could lead to huge sub-surface tunnels. These tunnels could have been carved out by lava flow. "They could shield human beings from space radiation and other hazards," Rao said.

ISRO is gearing up to finalise mission configuration of its second lunar foray with Chandrayaan-2, due for launch in 2013. The mission involves immense technical sophistication as it will have a lunar orbiter, which will disgorge a lunar lander, which in turn will release a lunar rover to crawl on the surface of the moon.

Dr Radhakrishnan revealed that, globally, scientists were discussing manned missions to Mars and establishing space colonies by 2030. He was confident that India would not lag too far behind. "India's first human space programme, which will have two astronauts in spacecraft orbiting the Earth, should be achieved in about six years," he said.