Dr. A new study from Western University shows that the early lunar crust that forms the Moon’s surface became significantly enriched in water more than 4 billion years ago, contrary to previous ideas. The discovery is described in a study published today (January 15) in the journal. Nature Astronomy.

Working with a meteorite that she classified as coming from the Moon as a graduate student at the Open University (UK), Tara Hayden first identified the mineral apatite (the most common phosphate) in a sample of early lunar crust. .

The study provides exciting new evidence that the early lunar crust contained more water than previously thought, opening new doors to the study of the moon’s history.

“Finding apatite for the first time in the early lunar crust is incredibly exciting because we can finally start to piece together this unknown phase of the lunar history. Hayden, who worked as a cosmochemist with renowned planetary geologist Gordon, said: “The early Moon’s crust is richer in water than we expected, and “We found that its volatile stable isotopes reveal a much more complex history than we previously knew,” said Osinski, from the Department of Western Earth Sciences.

“Lunar meteorites reveal exciting new parts of the Moon’s evolution and expand our knowledge beyond the samples collected during the Apollo missions.” “As we begin a new phase of lunar exploration, I can’t wait to see what we learn from the far side of the moon,” Hayden said.

After returning from the Moon, the Apollo samples were initially deemed “volatile-poor”, leading to the Moon being popularly described as “dried up”.

In 2008, Alberto Saal and other researchers found significant amounts of water and other volatiles in glass beads from the Apollo sample collection. This marked the beginning of a fifteen-year reanalysis of Apollo samples; Recently discovered lunar meteorites showed that there was much more water on the surface of the moon.

“We know much about the history of water on the Moon from Apollo samples, but these samples are thought to account for only five percent of the entire surface of the moon,” Hayden said. said. “Until we get more samples from future Artemis missions, the only surface samples we have are meteors.”

Hayden made this discovery during his PhD at the Open University. Research into testing a rock sample as a lunar meteorite for a collector. In addition to identification, the sample also appeared to contain an important piece of data about water on the moon.

“I’m very lucky that the meteorite not only came from the Moon, but also contains a surprising amount of chemicals that are vital to our understanding of the Moon’s water-bearing minerals,” Hayden said.

This study primarily focused on the apatite mineral, which contains volatile elements in its mineral structure. Apatite has been found in all lunar rock types except glass beads and ferrous anorthosite; the second represents the early crust of the Moon. The ferruginous anorthosite group is known to be incredibly old (4.5-4.3 billion years) and is the only type of rock known to have formed directly from the moon’s magma ocean, at a time when the moon was almost completely molten.

The discovery of apatite in such rocks allowed direct investigation of this unknown phase of the Moon’s evolution for the first time.

“Uncovering the history of water in the oldest lunar crust, which formed around 4.5 billion years ago, is important to improve our understanding of the origin of water in the Solar System,” said Mahesh Anand, professor of planetary science and research at the Open University and Hayden’s official principal investigator. “Old lunar rock samples in the form of lunar meteorites provide an excellent opportunity for such studies,” he said.

Future Artemis missions

Hayden says the timing of the discovery is perfect, as NASA’s Artemis missions are preparing for launch and researchers, including his current supervisor, are developing programs and goals for astronauts.

“For a long time it was thought that the lunar surface dried out over thousands or even millions of years, but there may be more water on the moon’s surface than we thought, and we just need to find a way to extract it.” said Hayden.

The Osinskis are equally excited about the potential of this new discovery.

Last year, Osinski was selected to serve on the NASA geology team that developed a plan to study the surface of the first manned lunar landing mission in more than 50 years. He will join colleagues in the Mission Management Science division at NASA’s Johnson Space Center in Houston, who will provide support throughout the Artemis III mission.

“Tara’s findings are extremely exciting and will feed into our sampling strategy for the Artemis III mission, where we hope to identify and sample some of the oldest layers of the lunar crust,” Osinski said.