By Aroonim Bhuyan, IANS,
Dubai : New research findings about evidence of water on the moon give fresh impetus to Chandrayaan, India’s maiden moon mission.
According to K. Kasturirangan, the man responsible for putting together the team for Indian space science’s most ambitious project, if the mission manages to find evidence of water on the moon, that would count among its biggest achievements.
“For me personally, if Chandrayaan-I manages to find evidence of water on the moon, then that would be the biggest achievement,” Kasturirangan, the director of the National Institute of Advanced Studies, told IANS when he visited the United Arab Emirates (UAE) recently.
An American university research team has for the first time discovered evidence of water that came from deep within the moon, a revelation that strongly suggests water has been a part of the moon since its early existence.
Brown University researchers believe water was contained in magma that erupted from fire fountains onto the surface of the moon more than three billion years ago.
Though about 95 percent of the water vapour from the magma was lost to space during this eruptive “degassing”, the researchers say that traces of water vapour may have drifted toward the cold poles of the moon, where they may remain as ice in permanently shadowed craters.
Which is where India’s Chandrayaan mission comes into the picture – it will try to find evidence of water near the previously unexplored polar regions of the moon.
Kasturirangan, a former chairman of the Indian Space Research Organization (ISRO), explained that hopes of Chandrayaan-I finding water in the moon rest on the fact that the mission would go to previously unexplored territories of the moon.
“Previous missions all studied the equatorial region of the moon which is exposed to sunlight and had, therefore, little chance of having water. Chandrayaan will, however, explore the polar regions which have not been exposed to sunlight,” Kasturirangan said.
For the Brown University researchers, the water clue came from lunar volcanic glasses, pebble-like beads collected and returned to earth by NASA’s (National Aeronautics and Space Administration) Apollo missions in the late 1960s and early 1970s.
Since then, scientists sought to determine the content and origin of a class of chemical elements known as volatiles in the multicoloured glasses. In particular, they searched the glasses for signs of water. But such evidence had remained elusive, consistent with the general consensus that the moon is dry.
The researchers have now found that elusive evidence, which also provides pointers to the origin of the moon – another of Chandrayaan’s mission objectives.
There are four major theories of the moon’s origin.
The co-accretion theory says that both earth and the moon – as also the other planets and moons in the solar system – coalesced from a rotating disk of planetesimals, or celestial bodies, ranging in size from inches to miles across.
A second theory says that the moon was an outside celestial body that was captured by the earth’s gravity.
The third theory says that the earth had a ring of materials around it at the time of its creation, which later coalesced to form the moon.
A fourth, called the giant planetesimal collision theory, says that a giant planetesimal collided with the earth, taking a chunk off it, which later became the moon.
“It is the fourth theory that is the most plausible,” Kasturirangan said.
“The mission will seek to find out how similar the crust of the moon is to that of the earth and that will give answers to several outstanding questions of the moon’s origin,” explained the recipient of Padma Vibhushan, India’s second highest civilian honour.
NASA is likely to send its Lunar Reconnaissance Orbiter later this year to search for evidence of water ice at the moon’s south pole. Question is: can Chandrayaan, planned for a September 2008 launch, do it before that?