India will launch its first unmanned mission to the Moon on October 22, the country's space officials say, weather conditions permitting.

The spacecraft, named Chandrayaan-1, will orbit the Moon, surveying its surface with high-resolution equipment.

The launch had been scheduled for April, but was pushed back due to technical problems.

The project will cost $83m and has the direct involvement of six other countries, including the US and Europe.

Over the next two years, it will survey the lunar surface to produce a complete map of its chemical characteristics and its three-dimensional topography.

The European Space Agency (ESA) is supporting the mission, supplying three instruments.

These will investigate the Moon's surface and near-surface composition, and the way the lunar body interacts with the fast-moving particles streaming away from the Sun.

Chandrayaan-1 will also drop a small impact probe on to the lunar surface to test its properties.

'Over ambitious'

India announced its Moon mission in 2003.

It has also announced plans to send a man to the Moon in the next few years.

The government's lunar activities have not been welcomed by all, however.

Critics say it is "over ambitious" and a "waste of resources" in a country where millions still lack basic services.

The Indian Space Research Organization (ISRO), was founded in 1969, and launched its first satellite in 1975.

Since then, it has developed a number of launch vehicles as well as satellites for Earth observation, telecommunications and weather forecasting.

Together with China and Japan, it is part of a fast-developing Asian space sector.