Tag Archive for James Greenwood

Faculty, Students Win Research Support from NASA’s CT Space Grant Consortium

The Van Vleck Observatory on Foss Hill.

The Van Vleck Observatory on Foss Hill.

Two faculty members and three students have been awarded grants in the latest call for proposals from NASA’s Connecticut Space Grant Consortium.

Jim Greenwood, assistant professor of earth and environmental sciences, and Bill Herbst, the John Monroe Van Vleck Professor of Astronomy, professor of integrative sciences, were awarded $8,000 for a Faculty Collaboration Grant titled “Chondrule Formation Experiments.” This is to run high-temperature experiments on material that makes up meteorites in order to test a hypothesis that they put forward in a recent paper in Icarus this year.

Seth Redfield, associate professor of astronomy, associate professor of integrative sciences, was awarded $1,500 for a STEM Education Programming Grant

Herbst, Greenwood Co-Author Article on Chondrules

Bill Herbst

Bill Herbst

Bill Herbst, the John Monroe Van Vleck Professor of Astronomy, and James Greenwood, assistant professor of earth and environmental sciences, co-authored an article published in the planetary science journal Icarus. Their article, “A New Mechanism for Chondrule Formation: Radiative Heating by Hot Planetesimals” grew out of research seminars from the recently introduced Planetary Science graduate concentration and minor at Wesleyan.

Their work focused on chondrules, or tiny spheres of molten rock that permeate primitive meteorites and date to very close to the beginning of the solar system.

For decades, the existence of chondrules has puzzled astrophysicists and cosmochemists as no obvious heat source exists at the time and location of their formation. Herbst and Greenwood set out to find this elusive heat source by combining their expertise in astronomy and earth science, respectively.

Jim Greenwood

James Greenwood

“It could be that the heat source is hot lava — oceans of magma– that may appear on nascent planets in their earliest days. The heat source is radioactive decay of a short-lived isotope of Aluminum, incubated in planetesimals with the size of small asteroids and brought to the surface as molten rock,” Herbst said.

Most of the material available for planet formation ends up on a planet very early on. A few “lucky bits,” represented by the primitive meteorites, avoided collision with a planet until just recently.

“It is, perhaps, not surprising that many, if not all of them, had a close encounter with a hot planetesimal that produced the chondrules and, likely, the chondritic meteorite in which they are embedded,” he said.

NASA Supports Greenwood’s Extraterrestrial Materials Research

James “Jim” Greenwood

Jim Greenwood

Jim Greenwood, assistant professor of earth and environmental sciences, was awarded a Faculty Seed Research Grant from the Connecticut Space Grant Consortium, supported by NASA. The honor comes with a $6,000 award.

Greenwood will use the grant to support his research on “D/H of ‘Dry’ Extraterrestrial Materials.”

Understanding the distribution, delivery, and processing of volatiles in the solar system is of fundamental interest to planetary science. Volatiles influence a number of important properties of planetary bodies, such as the cooling, differentiation, volcanism, tectonism, climate, hydrosphere/atmospheres and especially habitability.

Greenwood will use the award to develop a new state-of-the-art inlet system for the measurement of hydrogen and water and their hydrogen isotope composition in nominally anhydrous extraterrestrial materials. This inlet system will work in conjunction with the Wesleyan Hydrogen Isotope Mass Spectrometer, a Thermo Delta Advantage isotope ratio mass spectrometer installed in August 2014.

With the new system in place by the end of the project period, Greenwood and fellow researchers will be in position to measure hydrogen and water in two Apollo mare basalt rock samples.

“This will increase sensitivity for water by 250x our current measurement,” Greenwood said. “The added capability will allow us to make new and exciting measurements of volatiles in important planetary materials, such as these lunar rock samples.”

Read past News @ Wesleyan stories on Greenwood here.

Singer ’15 to Study Moon Rocks as Connecticut Space Grant Fellow

Jack Singer '15 holds a fragmented lunar sample (Apollo 12039,3), a crucial sample for studying his mineral of interest — apatite — on the moon.

Jack Singer ’15 holds a fragmented lunar sample (Apollo 12039,3), a crucial sample for studying his mineral of interest — apatite — on the moon. This summer, Singer received a Connecticut Space Grant College Consortium grant to fund his summer research in the Earth and Environmental Sciences Department.

As a recent recipient of an undergraduate research fellowship, Jack Singer ’15 is spending his summer at Wesleyan studying the geochemical evolution of the moon. 

The fellowship, supported by the Connecticut Space Grant College Consortium, comes with a $5,000 award. Grantees are expected to work on research related to space/aerospace science or engineering under the guidance of a faculty member or a mentor from industry.

By using a microscope in Wesleyan's Solar Systems Geochemistry Lab, Jack Singer takes a closer look at a Lunar sample.

By using a microscope in Wesleyan’s Solar Systems Geochemistry Lab, Jack Singer takes a closer look at a lunar sample.

For the next three months, Singer will work on various research projects with his advisor James Greenwood, assistant professor of earth and environmental science. Singer will first prepare a fragmented lunar sample (Apollo 12035,76) for analysis under an ion microprobe. An ion microprobe applies a beam of charged ions to the sample and helps determine the composition of the material.

This rock contains olivine, a mineral that is mysteriously sparse in many different lunar samples.

“By analyzing the melt inclusions contained within olivine in this rock, I’ll be able to better understand geochemical evolution of the moon,” Singer said.

Singer’s second project is more experimental. He’s attempting to model and quantify diffusion in a late-stage lunar environment (one of the last regions to cool on the moon) by synthesizing a granite-rich model lunar glass.

Singer will heat this glass past its melting point and place it in contact with solid terrestrial apatite — the Moon’s major water-bearing mineral — and measure how elements diffuse across the glass-grain (or solid-liquid) boundary.

Jack Singer and his advisor, James Greenwood, will travel to Japan this summer to use an ion microprobe at Hokkaido University.

Jack Singer and his advisor, James Greenwood, will travel to Japan this summer to use an ion microprobe at Hokkaido University.

“This type of analysis helps us to better understand the processes that occurred during the last stages of lunar cooling,” he explained.

In addition, Singer and Greenwood will travel to Japan this summer to use an ion microprobe at Hokkaido University.

“This machine allows us to analyze and measure stable isotope ratios in the minerals we are interested in, and can therefore tell us something about the fractionation and geochemical history of the lunar body,” Singer said.

Next fall, Singer will write about his research findings.

NASA Supports Greenwood’s Research on the Moon’s Water

James “Jim” Greenwood

James “Jim” Greenwood

Assistant Professor of Earth and Environmental Sciences James “Jim” Greenwood has received a $331,000 grant from NASA to support his research on the moon’s water.

His proposed research, tracking water in rock samples brought back by the Apollo missions, will “take a giant leap towards solving one of the most important questions in planetary science – whether the Moon is wet or dry,” Greenwood said.

“We’ll be studying pockets of glass trapped in early and late-crystallizing minerals in lunar mare basalt samples,” Greenwood said. “We will measure water and other volatile elements in these trapped melt pockets to reconstruct the volatile history of the samples as they cooled and crystallized near the lunar surface.”

The NASA grant is part of NASA’s Lunar Advanced Science and Exploration Research program.

Greenwood intends to use the grant, which will be distributed over four fiscal years, to fund one Wesleyan undergraduate per summer to conduct research in his lab. The grant will also allow Greenwood to do critical measurement work at Hokkaido University in Sapporo, Japan.

This project is only the latest initiative in Greenwood’s intensive work on lunar rocks, and the Moon’s relative wetness. Most recently he and four colleagues co-authored a paper in the prestigious journal Science, casting doubt on the theory of abundant lunar water, while simultaneously boosting theories around the Moon’s creation, several billion years ago.

 

Greenwood, Colleagues Debunk Sloshy Lunar Theory

James Greenwood, assistant professor of earth and environmental sciences, studies the potential of water on the moon.

James Greenwood, assistant professor of earth and environmental sciences, studies the potential of water on the moon.

James “Jim” Greenwood, assistant professor of earth and environmental sciences, and four colleagues have published a paper that casts doubt on the theory of abundant water on the moon while simultaneously boosting theories around the creation of the moon, several billion years ago.

The paper, “The Lunar Apatite Paradox,” published March 20 in the prestigious journal Science, stems from work involving the mineral apatite, the most abundant phosphate in the solar system. (Along with its presence on planets, it’s found in teeth and bones.)

Initial work on the lunar rocks brought back to Earth by the Apollo missions indicated that the Moon was extremely dry. Any evidence of water was dismissed as contamination from Earth.

But more recent experiments have shown the presence of plenty of water in grains of apatite derived from lunar rocks. Greenwood and colleagues sought to figure out whether, or how that could be.

“We formulated a solution to the problem of how you get this much water into moon apatite by using a mathematical model,” Greenwood said.

Gilmore, Greenwood, Martin ’14, Dottin ’13 Attend Planetary Science Conference

At left, James Dottin '13 and Peter Martin '14 reunited at the Lunar and Planetary Science Conference in March. Both presented papers at the annual conference.

At left, James Dottin ’13 and Peter Martin ’14 reunited at the Lunar and Planetary Science Conference in March. Both presented papers at the annual conference.

Two faculty, one student and one alumnus made paper presentations at the 45th Lunar and Planetary Science Conference in The Woodlands, Tex., March 17-21.

The Planetary Science Conference brings together international specialists in petrology, geochemistry, geophysics, geology and astronomy to present the latest results of research in planetary science. The five-day conference included topical symposia and problem-oriented sessions. During the conference, Marty Gilmore, chair and associate professor of earth and environmental sciences, presented a paper on the “Venus Exploration Roadmap to the Venus Exploration Analysis Group (VEXAG)” on March 20.

James Greenwood, assistant professor of earth and environmental sciences, presented “Hydrogen Isotopes of Water in the Moon: Evidence for the Giant Impact Model from Melt Inclusion and Apatite in Apollo Rock Samples,” on March 19.

Peter Martin '14 presented a poster titled "Modeling and Mineralogical Analyses of Potential Martian Chloride Brines."

Peter Martin ’14 presented a poster titled “Modeling and Mineralogical Analyses of Potential Martian Chloride Brines.”

Peter Martin ’14 presented his research on “Modeling and Mineralogical Analyses of Potential Martian Chloride Brines” on March 20.  Martin’s travel to the conference was funded by a Connecticut Space Grant and a USRA Thomas R. McGetchin Memorial Scholarship Award. Gilmore is Martin’s advisor.

James Dottin ’13, who is currently a Ph.D. student in geology at the University of Maryland,  spoke on “Isotope Evidence for Links between Sulfate Assimilation and Oxidation of Martian melts from Meteorites MIL 03346, MIL 090030, MIL 090032 and MIL 090136” on March 21.  While at Wesleyan, Dottin participated in the McNair Program. Greenwood was Dotton’s advisor.

Gilmore also presented a paper on “Are Martian Carbonates Hiding in Plain Sight? VNIR Spectra of Hydrous Carbonates,” which was co-authored by Patrick Harner MA ’13. Harner is a Ph.D. student at the Lunar and Planetary Laboratory at the University of Arizona. Harner completed this research while a student at Wesleyan.

Greenwood’s Study Published in Science

James “Jim” Greenwood, assistant professor of earth and environmental sciences, and four colleagues have co-authored a paper titled “The Lunar Apatite Paradox,” published in the  journal Science on March 20. 

The study casts doubt on the theory of abundant water on the moon while simultaneously boosting theories around the creation of the moon, several billion years ago.

NASA Funds Greenwood’s Lunar Rock Study

Jim Greenwood

James Greenwood, research associate professor of earth and environmental sciences, received a grant worth $494,517 from NASA. The grant will support his research titled “Water in Lunar Rocks: Petrologic and Isotopic Analyses of Phosphate Minerals in Apollo’s Samples” through June 30, 2014.

Greenwood Mentioned on BBC News Regarding Water in Lunar Rocks

James Greenwood, visiting assistant professor of earth and environmental sciences, was mentioned in a June 14 BBC News science article on “Much More Water Found in Lunar Rocks.”

Greenwood and Professor Lawrence Taylor from the University of Tennessee in Knoxville, have come up with evidence on the origins of lunar water: comets. According to the article, they believe there were a lot of comets flying around at the time of the Moon’s formation, “hitting the little, nascent, early Moon some 4.5 billion years ago.”

Greenwood Finds Water in Moon Rocks

Jim Greenwood, research assistant professor of earth and environmental sciences, holds a slide with a moon rock sample that contains water. The water was found in the mineral apatite, which he and his team were able to identify in the sample. (Photo by Olivia Bartlett Drake)
Jim Greenwood, research assistant professor of earth and environmental sciences, holds a slide with a moon rock sample that contains water. The water was found in the mineral apatite, which he and his team were able to identify in the sample. (Photo by Olivia Bartlett Drake)

Soon after the Apollo spaceflights to the moon, experts examined the rocks brought back by the astronauts and declared with certainty that the moon was a dry, waterless place.

Forty years later, James Greenwood begs to differ. Not only does he have proof, his findings strongly suggest that some of the lunar water he found is not indigenous to the moon or earth but appears to have originated from somewhere else in space.

Greenwood, research associate professor, visiting assistant professor, Earth and Environmental Sciences, pioneered a new method of analyzing the rocks using a combination of light, electron and ion-beam microscopes. He and his international team of planetary geologists and geochemists, announced their findings at the 41st Annual Lunar and Planetary Science Conference in Houston, Texas, in March.

It was a discovery almost didn’t happen, however. In fact, the only reason Greenwood found proof of water on the moon was because he was looking at a rock from Mars.

“I was in a lab at Hokkaido University in Sapporo, Japan, using an ion microscope to measure water in Martian meteorites,” Greenwood, who is a planetary geochemist, says. “We had pioneered this new technique to use two-dimensional ion imaging and were looking at this mineral in the meteorites called ‘apatite,’ which is a common phosphate mineral and holds water. Our analyses had been very good, probably better than ever before. So I thought, ‘What if we used this technique on moon rocks?’”

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Greenwood thought of moon rocks because a 2008 study from Brown University had found possible evidence of water in volcanic moon rocks. However, the study had been problematic and its results disputed. Still, Greenwood was intrigued that the possibility of water in the lunar rock samples had not been thoroughly vetted.

“The rocks were all declared devoid of water when they were first analyzed 40 years ago,” he said. “But I thought our new technique held some promise.”

Greenwood’s technique and the advanced instruments he gained access to, made it possible for him and the other scientists on his team to analyze the sample’s chemical composition over areas as small as 5 x 5 microns.

“In the past, they had actually ground up the analyzed samples. This created conditions that put the chemical analysis out of context,” he says. “Our method let us look at the samples as they are, in situ.”

The hardest part was getting permission to examine a sample. Less than 900 rocks were brought back from all the Apollo missions combined. Access is strictly limited.

It took several months, but Greenwood was able to get a few samples to analyze. The first were from the lunar highlands, which he thought might hold promise. But no water-holding apatite was found. Then he gained access to a sliver of rock brought back from the southwestern edge of the Mare Tranquillitatis – the “Sea of Tranquility” – where Apollo 11 had set down in 1969.

“So there we were in the lab at about 3 a.m. and the first sample we looked at, boom, there it was. Water. At first we couldn’t believe it. But we double-checked and we were just blown away. It was clearly there.”

The apatite, which is the same mineral that teeth are made of, was rife with water molecules. However, as Greenwood and his colleagues continued to analyze the samples they found that the water contained in the rocks was not from the earth or the moon.

“It was consistent in the water that comes from comets,” Greenwood says.

How could he tell? Water molecules found on earth – and those indigenous to the moon, since it was once part of the earth – contain a specific ratio of hydrogen to deuterium, which scientists use as a standard. The water Greenwood has found in some of the lunar samples has nearly twice the deuterium.

“The only things that falls into this range with any consistency are comets,” Greenwood says.

He adds that comets have long been known to hold frozen water and that perhaps as much as 10% of the earth’s water had come from comets, as well.

Microscopic water in minerals inside moon rocks is a tremendous find, but in a practical sense it does not open the door to, say, astronauts extracting this water to use on a lunar base or colony. Greenwood says that process would be too expensive and energy-exclusive with current methods. However, his discovery does open up another possibility.

“The level of water we found in the samples are consistent with the amount of water one would find from the mantle in the earth,” he says. “So there may be a reservoir of water within the mantle of the moon. Somewhat like groundwater here on earth.”

How far within the mantle, how deep below the surface is another challenge for another completely different type of study.

But Greenwood and his team have confirmed what many people have wondered for centuries, perhaps millennia. There is water on the moon.