Bangalore: India's maiden lunar mission Chandrayaan-1 is likely to lift off in the early hours of Oct 22 from the Satish Dhawan Space Centre at Sriharikota, about 90km from Chennai, a top space agency official said Monday.

"The tentative launch date is Oct 22 though the window will be kept open till Oct 26. Depending on the weather, we plan to launch the lunar spacecraft (Chandrayaan) around 6.30 a.m. IST," Indian Space Research Organisation (ISRO) director S. Satish told IANS here.

The 1,380 kg spacecraft, built at ISRO's satellite centre in this IT hub, will be carried into lunar orbit by a specially designed 320-tonne Polar Satellite Launch Vehicle (PSLV-C11), with six strap-on propellants weighing 12 tonnes each.

"The formal countdown will begin 50 hours before the launch in the early hours of Oct 20. All going well and weather permitting, the final countdown will begin hours before the actual launch on Oct 22," Satish said.

The indigenous spacecraft is in the process of being integrated with the PSLV rocket at the SHAR launchpad, situated off the Bay of Bengal in Nellore district of Andhra Pradesh.

"The integration will be completed by this week-end. All systems and instruments will be checked and tested for operational purposes," Satish noted.

The Rs 3.9-billion Chandrayaan has 11 payloads, including five from India and six from the US, Europe and Bulgaria.

"The spacecraft will orbit around the moon at an altitude of 100 km to map the topography and the mineralogical resources of the lunar soil," Satish added.

Chandrayaan-1 will also carry a moon impact probe payload for demonstrating the technology needed towards landing on the moon's surface in subsequent missions.