In Nature Geoscience this month, an article entitled “Remote detection of widespread indigenous water in lunar pyroclastic deposits,” researchers Ralph Milliken and Shuai Li, the former an associate professor at Brown University, and the latter a Brown post-grad doing research at University of Hawaii, describe evidence of “significant water in the bulk lunar mantle.”

They began studying rocks brought back from the Apollo missions and discovered traces of water that could not be explained by contamination. In other words, Moon rocks were a bit wet, similar to basaltic rocks here on Earth. Milliken and Li then studied data collected by the Moon Mineralogy Mapper instrument on India’s Chandrayaan-1, a lunar orbiter that successfully mapped the geology of the Moon from 2008 to 2009. From the images, the researchers were able to deconstruct reflected sunlight and heat while examining pyroclastic (volcanically derived) surface deposits. They were then able to determine the content of the rocks. What they found was water in nearly every pyroclastic deposit including those near the Apollo 15 and 17 landing sites. This confirmed that the presence of water in Apollo Moon rocks was no fluke. The Moon was in fact water rich.

In a July 24, 2017, press release, Milliken notes that water signatures visible in the data were consistent with that from Apollo and Soviet Luna mission samples. He continues, “The distribution of these water-rich deposits is the key….They’re spread across the surface, which tells us that the water found in the Apollo samples isn’t a one-off. Lunar pyroclastics seem to be universally water-rich, which suggests the same may be true of the mantle.” 

Based on the impact theories for lunar creation it is a bit of puzzle to explain how the lunar interior could contain so much water, about 0.5% by weight. If the Moon was born from a planet-sized object colliding with the early Earth, one would theorize that any water present, in particular, the hydrogen component, would be lost to space. In such a scenario the interior of the Moon should be bone dry. But these discoveries prove otherwise with some interesting implications.  More accessible water resources than those at the lunar poles increases the options available for future locations of human-occupied lunar bases. It means water can be mined rather than having to be trucked from Earth, or harvested from a near-Earth asteroid.

States Li in the press release, “Anything that helps save future lunar explorers from having to bring lots of water from home is a big step forward.”

Dating back to 1975 when India launched its first satellite from the Soviet Union, the country has been slowly developing a program with the goal to eventually put Indian astronauts into space. And today it continues to combine launch using foreign rockets as well as its own domestically designed vehicles to put satellites into space.

The PSLV first appeared in 2001 followed by its much larger cousin, the GSLV in 2004. In 2008 India launched Chandrayaan-1, a mission to place a satellite into lunar orbit. The orbiter operated successfully for 10 months before its on board power supply failed.

So what next for India’s Space Research Organisation, known by the acronym ISRO? A Mars orbiter mission is planned for late in the year. And further work on the GSLV launch vehicle may soon make it reliable enough to consider human space launches. Glitches with the upper stage of the GSLV has been the single biggest impediment to India joining the U.S., Russia and China as a space faring nation. But ISRO continues to look to achieving human space flight with a reworked GSLV as the launch vehicle before 2017. The agency has even discussed with Russia if there is available mothballed technology such as human lander that could be acquired for a mission to the Moon.

But it is more likely that India will not be sending human crews into space until early in the next decade. In the interim the country will continue to launch satellites for remote sensing. Plans include the development of an independent global positioning network. And the country remains committed to a second lunar mission within the next two years. Dubbed Chandrayaan-2, it will consist of both an orbiter and rover and will be launched using an improved GSLV.

ISRO’s advanced launch vehicles can be seen in the image below. On the left is the PSLV while the two on the right are the GSLV and the heavier launch vehicle the GSLV Mark III. It is the latter and its successors that will give India the capability to achieve human space flight.