Since man first touched the moon and brought pieces of it back to Earth, scientists have thought that the lunar surface was bone dry. But new observations from three different spacecraft have put this notion to rest with what has been called "unambiguous evidence" of water across the surface of the moon.
Forget that tired old image of the moon as an entirely dry locale, devoid of any moisture. A recent set of discoveries have found that not only is there water on Earth's sole satellite — but the water is everywhere
The Moon is Earth's only natural satellite and the fifth largest satellite in the Solar System. The Moon is in synchronous rotation, which means it rotates about its axis in about the same time it takes to orbit the Earth. This result in it keeping nearly the same face turned towards the Earth at all times. The Moon used to rotate at a faster rate, but early in its history, its rotation slowed and became locked in this orientation as a result of frictional effects associated with tidal deformations caused by the Earth.
The Moon is the only celestial body on which human beings (home sapiens) have made a manned landing. While the erstwhile Soviet Union's Luna programme was the first to reach the Moon with unmanned spacecraft, the NASA Apollo program achieved the only manned missions to date, beginning with the first manned lunar mission by Apollo 8 in 1968, and six manned lunar landings between 1969 and 1972 – the first being Apollo 11 in 1969. Human exploration of the Moon temporarily ceased with the conclusion of the Apollo program, although a few robotic landers and orbiters have been sent to the Moon since that time. The U.S. has committed to return to the Moon by 2018 and I am not much impressed by the conspiracy theories indicating that the Americans never landed on moon in the first place and all these manned spaceflights have been nothing but utter hogwash…
According to Wikipedia…
The continuous bombardment of the Moon by comets and meteoroids has most likely added small amounts of water to the lunar surface. If so, sunlight would split much of this water into its constituent elements of hydrogen and oxygen, both of which would ordinarily escape into space over time, because of the Moon's weak gravity. However, because of the slightness of the axial tilt of the Moon's spin axis to the ecliptic plane—only 1.5°—some deep craters near the poles never receive direct light from the Sun and are thus in permanent shadow. Water molecules that ended up in these craters could be stable for long periods of time.
Clementine has mapped craters at the lunar south pole that are shadowed in this way, and computer simulations suggest that up to 14,000 km² might be in permanent shadow. Results from the Clementine mission bistatic radar experiment are consistent with small, frozen pockets of water close to the surface, and data from the Lunar Prospector neutron spectrometer indicate that anomalously high concentrations of hydrogen are present in the upper meter of the regolith near the Polar Regions. Estimates for the total quantity of water ice are close to one cubic kilometer.
Water ice can be mined and then split into its constituent hydrogen and oxygen atoms by means of nuclear generators or electric power stations equipped with solar panels. The presence of usable quantities of water on the Moon is an important factor in rendering lunar habitation cost-effective, since transporting water from Earth would be prohibitively expensive. However, recent observations made with the Arecibo planetary radar suggest that some of the near-polar Clementine radar data that were previously interpreted as being indicative of water ice might instead be a result of rocks ejected from young impact craters. The question of how much water there is on the Moon has not been resolved conclusively.
Three papers appearing in the upcoming issue of Science Express outline the discovery of pervasive water found clinging to the surface of the moon. Infrared spectroscope measurements from three different space probes have detected absorptions that indicate the presence of water or hydroxyl (which is, itself, a strong indicator for the presence of water) on the lunar surface, with one model suggesting water makes up a few tenths of a percent by weight in the optical surface. This water is apparently clinging to the moon's surface, rather than being absorbed by dust.
India's own Moon Impact Probe (MIP) on board the country's maiden lunar craft had discovered water on the moon, a finding confirmed by US space agency NASA's probe that was also aboard Chandrayaan-1.
India's first moon mission has achieved a historic first by discovering water on the lunar surface. This is being hailed not only as a landmark breakthrough in space science but also as a vindication of the mission itself, since the two year project got terminated after just 10 months.
Predictably - India's first lunar mission had made a "path-breaking and real discovery" by establishing the presence of water on the moon, Indian Space Research Organization (ISRO) chairman Nair said. While expressing pride in the achievement, Nair added: "But the water is not in the form of sea or lake or puddle or drops. It is embedded on the surface in minerals and rocks.” Scientists confirming the presence of water on the moon are doing so on the basis of scientific findings that have been arrived at after a rigorous process of deduction and analysis and not by actually finding lakes, pools or puddles of water that we're familiar with on earth. It's hardly a vast lake, and it won't yet support that lunar agricultural colony you've been dreaming of, but it's far more water than scientists ever expected to find on the moon, and it could prove a valuable resource to future lunar visitors.
The researchers have also found that the concentration of water is higher toward the poles, lending credence to the theory that larger deposits of water exist near the poles, and researchers note that it's possible we'll continue to find wetter lunar regions in the future.
So where did all this water come from? Although meteors or comets may have periodically brought water to the moon, the prevailing theory among the three papers is that solar winds have carried hydrogen to the moon's surface, where it has bonded with the oxygen in the moon's own dust and produced water.
However, according to Mylswamy Annadurai, Chandrayaan-1 project director, the water molecules came from the Moon surface — a major revelation made possible by the Indian mission. This dispels the age-old belief and the current thinking that only other planetary bodies can be the source of water molecules on the Moon. According to ISRO scientists, this mission has changed the thinking. The new theory is that the water molecules are not from an outside source, but are being generated then and there. This is now being analyzed.
According to a space.com article - There are potentially two types of water on the moon: that brought from outside sources, such as water-bearing comets striking the surface, or that that originates on the moon.
It is really one of those moments in human history which can prove as a turning point. Finding water on the moon would be a boon to possible future lunar bases, acting as a potential source of drinking water and fuel.
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