More evidence of water on Moon

Last year, scientists had confirmed the existence of water on Moon following several lunar missions, including India's Chandrayaan-1 probe.

Now, the discovery by geologists at the California Institute of Technology (Caltech) and the Tennessee University suggested that it would be far easier for humans to one day set up a space station on the moon's surface, the Daily Mail reported.

The discovery was made after the team examined a basalt rock underlying the Moon's surface that was formed by lava flows billions of years ago and brought back to Earth by the 1971 Apollo 14 mission.

They found evidence of hydroxide ions -- negatively charged molecules identical to those of water but missing one hydrogen atom in apatite, a calcium phosphate mineral.

Professor George Rossman, of the California Institute of Technology, said: "If you heat up the apatite, the hydroxyl ions will 'decompose' and come out as water."

The team said this provides "robust evidence for the presence of water in the interior of the moon from where some lunar rocks were derived.

"This demonstrates a closer chemical and geologic relationship between the Earth and moon than previously known. We must now re-evaluate the volatile inventories of the Moon, relative to the Earth."

Reporting their findings in the journal Nature, the researchers said ubiquitous water on the Moon could mean a human settlement on the moon is not so far-fetched.

Currently the endeavour would be very expensive. For example, it costs USD 25,000 to take one pint of water to the moon.

But if scientists devise processes to easily recover this water from the lunar rocks for drinking water and fuel, a human settlement is not out of reach, the scientists said.
Space scientist Professor Lawrence Taylor of Tennessee University said: "Now we have ready sources of water that can be consumed by plants and humans but also electrolysed into liquid hydrogen and liquid oxygen to develop rocket fuel.

"Until the recent discovery of water in and on the Moon, it was going to be a very energy-intensive endeavour to separate these elements from the lunar rocks and soil."

The breakthrough follows identification last year by Prof Taylor and colleagues of 'lunar dew' on the Moon's surface -- absorbed 'water' in the uppermost layers of the soil.
The finding also has deep implications for how the Moon and the Earth formed.

It is generally believed the Moon was created when the early Earth was hit by a Mars-sized proto-planet called Theia, melting and vaporising itself and a large chunk of the Earth.

The cloud of particles created by the impact later congealed to form the Moon, which supposedly was devoid of highly volatile elements such as hydrogen and chlorine.
However, the researchers' discovery of these volatiles challenges this theory.

Co-researcher Dr Yang Liu of Tennessee University said: "If water in the Moon was residue water kept during the giant impact, it is surprising that water survived the impact at all because less volatile elements, such as sodium and potassium, are strongly depleted."