"There is confirmation of traces of water.It is a path-breaking event as far as Chandrayaan-1 mission is concerned. It is very very significant. So far, no mission has confirmed the presence of water positively," he said.
One of the major instruments that gave the data was Moon Mineralogy Mapper of NASA, which was one of the payloads on board India's maiden Moon mission supplemented by hyper-spectral imager and moon impact probe of Indian Space Research Organisation.
The data analysis was done by scientists of Jet Propulsion Laboratory in the US and Physical Research Laboratory and Space Application Centre, both headquartered in Ahmedabad, he said.
Nair said ISRO would make a formal announcement and disclose detailed analysis tomorrow following the publication of findings in a science journal and announcement by NASA scientists.
Chandrayaan-1, launched in October last year, ended prematurely last month ahead of its two-year life span but Nair has maintained that it had achieved 95 per cent of its objectives.