India's Chandrayaan-2 lunar probe exited the Earth's orbit early Wednesday to embark on a journey to the Moon, the Indian Space Research Organisation (ISRO) said.

The 142-million-dollar mission aims to map the surface of the lunar south pole, examine its composition and search for water in 14 days of experiments.

The spacecraft will cover a distance of 384,000 kilometres over the next six days before ISRO officials fire its engine and insert it into the Moon's orbit.

The 3.8-tonne Chandrayaan-2 comprises an orbiter, lander and rover. The lander and rover are expected to touch down on an unexplored part of the south pole region on September 7, the ISRO said.

Chandrayaan-2 - whose name means ‘moon vehicle’ in Sanskrit - was launched from the Sriharikota spaceport in southern India on July 22 on a locally-built rocket.

ISRO chairman K Sivan has described the 15-minute final landing as the most complex mission ever undertaken by the agency.

If India succeeds, it will become the fourth country to achieve a soft landing on the Moon after the United States, the former Soviet Union and China. Chandrayaan-2 is the country's second lunar mission. The first mission Chandrayaan-1, launched in 2008 and orbited the Moon but did not land.