The Hyper-Spectral Imager (HySI) of ISRO supported M3 in recording the water signature very clearly.

In addition, NASA has got confirmation about the presence of water from the data sent by its Deep Impact Probe, which observed the moon for a week June 2-9, 2009, and from the analysis of archived data of lunar observation by its Cassini in 1999 on its way to Saturn.

'We had indication of this (water on moon) way back in June. But we did not want to announce it for the simple reason this is of such a global significance. It has to come in one of the well-established journals and Science Express has brought out this article. We have timed the announcement to that event,' Nair clarified.

Admitting that the water was not in the form of a sea, lake or even a puddle, Nair said it was embedded in the surface, minerals and rocks.

'We have clear indication that hydroxyl (OH) and water (H2O) molecules are present on the surface. The quantity found is much larger than what we expected. This is a real finding and we are happy to say that starting from 70 degrees latitude (of the moon) to the polar region, the intensity of the signatures goes up,' Nair noted.

The data has also revealed the temperature and variation of the content of the water on the surface.

'To extract water out of this, we have to evolve techniques and if we process one tonne of the soil, we may get half-litre of water. So, that is going to be the real challenge,' Nair said.

Terming the stunning discovery as the first in the history of space research, the top scientist said it was only a small step towards the scientific exploration of the planetary system.

'We have to go a long way. Our own instruments (five) have sent volumes of data, which are being compiled and analysed. It may take anywhere between six months and three years for the scientists to digest the massive data. More interesting findings will come out of this maiden lunar mission,' Nair added.