Evidence of water on the moon discovered in samples obtained from original Apollo missions

Called the “Genesis Rock,” this lunar sample of unbrecciated anorthosite collected during the Apollo 15 mission was thought to be a piece of the moon’s primordial crust. In a paper published online Feb. 17 in Nature Geoscience, a University of Michigan researcher and his colleagues report that traces of water were found in the rock. (Credit: Photo courtesy of NASA/Johnson Space Center)

Traces of water have been detected within the crystalline structure of mineral samples from the lunar highland upper crust obtained during the Apollo missions, according to a University of Michigan researcher and his colleagues.

The lunar highlands are thought to represent the original crust, crystallized from a magma ocean on a mostly molten early moon. The new findings indicate that the early moon was wet and that water there was not substantially lost during the moon’s formation.

The results seem to contradict the predominant lunar formation theory — that the moon was formed from debris generated during a giant impact between Earth and another planetary body, approximately the size of Mars, according to U-M’s Youxue Zhang and his colleagues.

“Because these are some of the oldest rocks from the moon, the water is inferred to have been in the moon when it formed,” Zhang said. “That is somewhat difficult to explain with the current popular moon-formation model, in which the moon formed by collecting the hot ejecta as the result of a super-giant impact of a martian-size body with the proto-Earth.

“Under that model, the hot ejecta should have been degassed almost completely, eliminating all water.”

A paper titled “Water in lunar anorthosites and evidence for a wet early moon” was published online Feb. 17 in the journal Nature Geoscience. The first author is Hejiu Hui, postdoctoral research associate of civil and environmental engineering and earth sciences at the University of Notre Dame. Hui received a doctorate at U-M under Zhang, a professor in the Department of Earth and Environmental Sciences and one of three co-authors of the Nature Geoscience paper.

Over the last five years, spacecraft observations and new lab measurements of Apollo lunar samples have overturned the long-held belief that the moon is bone-dry.

In 2008, laboratory measurement of Apollo lunar samples by ion microprobe detected indigenous hydrogen, inferred to be the water-related chemical species hydroxyl, in lunar volcanic glasses. In 2009, NASA’s Lunar Crater Observation and Sensing satellite, known as LCROSS, slammed into a permanently shadowed lunar crater and ejected a plume of material that was surprisingly rich in water ice.

Hydroxyls have also been detected in other volcanic rocks and in the lunar regolith, the layer of fine powder and rock fragments that coats the lunar surface. Hydroxyls, which consist of one atom of hydrogen and one of oxygen, were also detected in the lunar anorthosite study reported in Nature Geoscience.

In the latest work, Fourier-transform infrared spectroscopy was used to analyze the water content in grains of plagioclase feldspar from lunar anorthosites, highland rocks composed of more than 90 percent plagioclase. The bright-colored highlands rocks are thought to have formed early in the moon’s history when plagioclase crystallized from a magma ocean and floated to the surface.

The infrared spectroscopy work, which was conducted at Zhang’s U-M lab and co-author Anne Peslier’s lab, detected about 6 parts per million of water in the lunar anorthosites.

“The surprise discovery of this work is that in lunar rocks, even in nominally water-free minerals such as plagioclase feldspar, the water content can be detected,” said Zhang, the James R. O’Neil Collegiate Professor of Geological Sciences.

“It’s not ‘liquid’ water that was measured during these studies but hydroxyl groups distributed within the mineral grain,” said Notre Dame’s Hui. “We are able to detect those hydroxyl groups in the crystalline structure of the Apollo samples.”

The hydroxyl groups the team detected are evidence that the lunar interior contained significant water during the moon’s early molten state, before the crust solidified, and may have played a key role in the development of lunar basalts.

“The presence of water,” said Hui, “could imply a more prolonged solidification of the lunar magma ocean than the once-popular anhydrous moon scenario suggests.”

The researchers analyzed grains from ferroan anorthosites 15415 and 60015, as well as troctolite 76535. Ferroan anorthosite 15415 is one the best known rocks of the Apollo collection and is popularly called the Genesis Rock because the astronauts thought they had a piece of the moon’s primordial crust. It was collected on the rim of Apur Crater during the Apollo 15 mission.

Rock 60015 is highly shocked ferroan anorthosite collected near the lunar module during the Apollo 16 mission. Troctolite 76535 is a coarse-grained plutonic rock collected during the Apollo 17 mission.

Co-author Peslier is at Jacobs Technology and NASA’s Johnson Space Center. The fourth author of the Nature Geoscience paper, Clive Neal, is a professor of civil and environmental engineering and earth sciences at the University of Notre Dame. The work was supported by NASA.


Famously Reclusive Neil Armstrong Gives Exclusive Interview to Australian Accountant

It was one small interview for astronaut Neil Armstrong … and one giant scoop for an Australian accountant, of all people.

In the year’s most out-of-this-world get, the first man to step foot on the moon sat down with CPA (Certified Practicing Account) Australia’s Alex Malley to narrate his historic lunar landing in an extremely rare interview.

Armstrong was the commander of NASA’s three-man Apollo 11 mission that landed on the moon on July 20, 1969. Armstrong and fellow astronaut Buzz Aldrin spent about two hours on the surface before returning to the Eagle lunar module.

The 81-year old American is famously reluctant to discuss the moon landing and has granted very few interviews in the last 40 years — so why choose to open up to CPA Australia? Malley thinks he knows the answer.

“I knew something a lot of people didn’t know about Neil Armstrong — his dad was an auditor,” said Malley in the first of the four part interview with Armstrong posted on the CPA website.

In the 45-minute interview Commander Armstrong discussed his childhood in Ohio, walking on the moon, and what it’s like to sleep on a spaceship.

Armstrong also recounts the moment he got the call to ask him if his crew were ready to land on the moon.

“The bosses asked, ‘Do you think you and your guys are ready?” Armstrong recalled. “I said it’d be nice to have another month, but we’re in a race here and we had to take the opportunity when we had it. I had to say we are ready, we are ready to go.”

“I thought we had a 90% chance of getting back safely to Earth on that flight, but only a 50-50 chance of making a successful landing on the first attempt.”

Armstrong also details the crew’s harrowing 12-minute descent to the moon, when he realized that the Eagle lunar module’s auto-pilot was preparing to land the crew on the slope of a huge moon crater.

“The computer showed us where it intended to land, and it was a very bad location, on the side of a large crater about 100-150m in diameter with very steep slopes covered with very large boulders — not a good place to land at all,” he said.

Armstrong took over the craft manually and managed to land it like a helicopter in a smoother area to the west with just 20 seconds of fuel left. “Houston, Tranquility Base here. The Eagle has landed,” were Armstrong’s words to mission control on earth.

As for “That’s one small step for a man, one giant leap for mankind,” Armstrong says he didn’t think of those immortal words until after they’d landed safely.

The first few moments when Armstrong and Buzz Aldrin stepped out of the Eagle and onto the surface of the moon were tender, he remembers.

“We recognized that we wouldn’t have been there if it hadn’t been for our competitors in the Soviet Union — it was a competition that made both of our programs able to do what we achieved. We put medallions for our fallen colleagues on both sides, and that was a tender moment.”

Armstrong laughed off the conspiracy theorists who believe the 1969 moon landing was faked, telling CPA Australia’s Malley that “800,000 staff at NASA couldn’t possibly keep a secret.”

“People love conspiracy theories, but it was never a concern to me — because I know one day someone’s going to go fly back up there and pick up that camera I left,” he said.

As for the future direction of space travel, Armstrong worries about cuts to NASA’s budget, and says the space program remains an important source of motivation for young Americans.

NASA’s 2013 budget for the exploration of Mars was cut by 38%, and the budget for planetary exploration overall was reduced by $300 million — a major concern, according to Armstrong.

“NASA’s been one of the most successful public investments in motivating students to do well and achieve all they can achive, and it’s sad that we are turning the program in a direction where it will reduce the amount of motivation it provides to young people.”