From Brown University: “Differences between the Moon’s near and far sides linked to colossal ancient impact”

From Brown University

April 8, 2022
Kevin Stacey
kevin_stacey@brown.edu
401-863-3766

A new study reveals that an ancient collision on the Moon’s south pole changed patterns of convection in the lunar mantle, concentrating a suite of heat-producing elements on the nearside. Those elements played a role in creating the vast lunar mare visible from Earth. CREDIT: Matt Jones. https://www.eurasiareview.com

New research shows how the impact that created the Moon’s South Pole–Aitken basin is linked to the stark contrast in composition and appearance between the two sides of the Moon.

The face that the Moon shows to Earth looks far different from the one it hides on its far side. The nearside is dominated by the lunar mare — the vast, dark-colored remnants of ancient lava flows. The crater-pocked far side, on the other hand, is virtually devoid of large-scale mare features. Why the two sides are so different is one of the Moon’s most enduring mysteries.

Now, researchers have a new explanation for the two-faced Moon — one that relates to a giant impact billions of years ago near the Moon’s south pole.

A new study published in the journal Science Advances shows that the impact that formed the Moon’s giant South Pole–Aitken (SPA) basin would have created a massive plume of heat that propagated through the lunar interior. That plume would have carried certain materials — a suite of rare-Earth and heat-producing elements — to the Moon’s nearside. That concentration of elements would have contributed to the volcanism that created the nearside volcanic plains.

“We know that big impacts like the one that formed SPA would create a lot of heat,” said Matt Jones, a Ph.D. candidate at Brown University and the study’s lead author. “The question is how that heat affects the Moon’s interior dynamics. What we show is that under any plausible conditions at the time that SPA formed, it ends up concentrating these heat-producing elements on the nearside. We expect that this contributed to the mantle melting that produced the lava flows we see on the surface.”

The study was a collaboration between Jones and his advisor Alexander Evans, an assistant professor at Brown, along with researchers from Purdue University, The University of Arizona Lunar and Planetary Laboratory & Department of Planetary Sciences, Stanford University and NASA JPL/Caltech.

The Moon’s nearside (left) is dominated by vast volcanic deposits, while the far side (right) has far fewer). Why the two sides are so different is an enduring lunar mystery.

The differences between the near and far sides of the Moon were first revealed in the 1960s by the Soviet Luna missions and the U.S. Apollo program. While the differences in volcanic deposits are plain to see, future missions would reveal differences in the geochemical composition as well. The nearside is home to a compositional anomaly known as the Procellarum KREEP terrane (PKT) — a concentration of potassium (K), rare earth elements (REE), phosphorus (P), along with heat-producing elements like thorium. KREEP seems to be concentrated in and around Oceanus Procellarum, the largest of the nearside volcanic plains, but is sparse elsewhere on the Moon.

Some scientists have suspected a connection between the PKT and the nearside lava flows, but the question of why that suite of elements was concentrated on the nearside remained. This new study provides an explanation that is connected to the South Pole–Aitken basin, the second largest known impact crater in the solar system.

For the study, the researchers conducted computer simulations of how heat generated by a giant impact would alter patterns of convection in the Moon’s interior, and how that might redistribute KREEP material in the lunar mantle. KREEP is thought to represent the last part of the mantle to solidify after the Moon’s formation. As such, it likely formed the outermost layer of mantle, just beneath the lunar crust. Models of the lunar interior suggest that it should have been more or less evenly distributed beneath the surface. But this new model shows that the uniform distribution would be disrupted by the heat plume from the SPA impact.

According to the model, the KREEP material would have ridden the wave of heat emanating from the SPA impact zone like a surfer. As the heat plume spread beneath the Moon’s crust, that material was eventually delivered en masse to the nearside. The team ran simulations for a number of different impact scenarios, from dead-on hit to a glancing blow. While each produced differing heat patterns and mobilized KREEP to varying degrees, all created KREEP concentrations on the nearside, consistent with the PKT anomaly.

The researchers say the work provides a credible explanation for one of the Moon’s most enduring mysteries.

“How the PKT formed is arguably the most significant open question in lunar science,” Jones said. “And the South Pole–Aitken impact is one of the most significant events in lunar history. This work brings those two things together, and I think our results are really exciting.”

See the full article here .

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Welcome to Brown

Brown University is a private Ivy League research university in Providence, Rhode Island. Founded in 1764 as the College in the English Colony of Rhode Island and Providence Plantations, Brown is the seventh-oldest institution of higher education in the United States and one of the nine colonial colleges chartered before the American Revolution.

At its foundation, Brown University was the first college in North America to accept students regardless of their religious affiliation. The university is home to the oldest applied mathematics program in the United States, the oldest engineering program in the Ivy League, and the third-oldest medical program in New England. The university was one of the early doctoral-granting U.S. institutions in the late 19th century, adding masters and doctoral studies in 1887. In 1969, Brown adopted its “Open Curriculum” after a period of student lobbying. The new curriculum eliminated mandatory “general education” distribution requirements, made students “the architects of their own syllabus” and allowed them to take any course for a grade of satisfactory (Pass) or no-credit (Fail) which is unrecorded on external transcripts. In 1971, Brown’s coordinate women’s institution, Pembroke College, was fully merged into the university.

Admission is among the most selective in the United States; in 2021, the university reported an acceptance rate of 5.4%.

The university comprises the College; the Graduate School; Alpert Medical School; the School of Engineering; the School of Public Health and the School of Professional Studies. Brown’s international programs are organized through The Watson Institute for International and Public Affairs at Brown University , and the university is academically affiliated with the UChicago Marine Biological Laboratory in Woods Hole, Massachusetts (US) and The Rhode Island School of Design. In conjunction with the Rhode Island School of Design, Brown offers undergraduate and graduate dual degree programs.

Brown’s main campus is located in the College Hill neighborhood of Providence, Rhode Island. The university is surrounded by a federally listed architectural district with a dense concentration of Colonial-era buildings. Benefit Street, which runs along the western edge of the campus, contains one of the richest concentrations of 17th and 18th century architecture in the United States.

As of November 2019, nine Nobel Prize winners have been affiliated with Brown as alumni, faculty, or researchers, as well as seven National Humanities Medalists and ten National Medal of Science laureates. Other notable alumni include 26 Pulitzer Prize winners, 18 billionaires, one U.S. Supreme Court Chief Justice, four U.S. Secretaries of State, 99 members of the United States Congress, 57 Rhodes Scholars, 21 MacArthur Genius Fellows, and 37 Olympic medalists.

The foundation and the charter

In 1761, three residents of Newport, Rhode Island, drafted a petition to the colony’s General Assembly:

“That your Petitioners propose to open a literary institution or School for instructing young Gentlemen in the Languages, Mathematics, Geography & History, & such other branches of Knowledge as shall be desired. That for this End… it will be necessary… to erect a public Building or Buildings for the boarding of the youth & the Residence of the Professors.”

The three petitioners were Ezra Stiles, pastor of Newport’s Second Congregational Church and future president of Yale University; William Ellery, Jr., future signer of the United States Declaration of Independence; and Josias Lyndon, future governor of the colony. Stiles and Ellery later served as co-authors of the college’s charter two years later. The editor of Stiles’s papers observes, “This draft of a petition connects itself with other evidence of Dr. Stiles’s project for a Collegiate Institution in Rhode Island, before the charter of what became Brown University.”

The Philadelphia Association of Baptist Churches were also interested in establishing a college in Rhode Island—home of the mother church of their denomination. At the time, the Baptists were unrepresented among the colonial colleges; the Congregationalists had Harvard University and Yale University, the Presbyterians had the College of New Jersey (later Princeton University), and the Episcopalians had The William & Mary College and King’s College (later Columbia University). Isaac Backus, a historian of the New England Baptists and an inaugural trustee of Brown, wrote of the October 1762 resolution taken at Philadelphia:

“The Philadelphia Association obtained such an acquaintance with our affairs, as to bring them to an apprehension that it was practicable and expedient to erect a college in the Colony of Rhode-Island, under the chief direction of the Baptists; … Mr. James Manning, who took his first degree in New-Jersey college in September, 1762, was esteemed a suitable leader in this important work.”

James Manning arrived at Newport in July 1763 and was introduced to Stiles, who agreed to write the charter for the college. Stiles’ first draft was read to the General Assembly in August 1763 and rejected by Baptist members who worried that their denomination would be underrepresented in the College Board of Fellows. A revised charter written by Stiles and Ellery was adopted by the Rhode Island General Assembly on March 3, 1764, in East Greenwich.

In September 1764, the inaugural meeting of the corporation—the college’s governing body—was held in Newport’s Old Colony House. Governor Stephen Hopkins was chosen chancellor, former and future governor Samuel Ward vice chancellor, John Tillinghast treasurer, and Thomas Eyres secretary. The charter stipulated that the board of trustees should be composed of 22 Baptists, five Quakers, five Episcopalians, and four Congregationalists. Of the 12 Fellows, eight should be Baptists—including the college president—”and the rest indifferently of any or all Denominations.”

At the time of its creation, Brown’s charter was a uniquely progressive document. Other colleges had curricular strictures against opposing doctrines, while Brown’s charter asserted, “Sectarian differences of opinions, shall not make any Part of the Public and Classical Instruction.” The document additionally “recognized more broadly and fundamentally than any other [university charter] the principle of denominational cooperation.” The oft-repeated statement that Brown’s charter alone prohibited a religious test for College membership is inaccurate; other college charters were similarly liberal in that particular.

The college was founded as Rhode Island College, at the site of the First Baptist Church in Warren, Rhode Island. James Manning was sworn in as the college’s first president in 1765 and remained in the role until 1791. In 1766, the college authorized Rev. Morgan Edwards to travel to Europe to “solicit Benefactions for this Institution.” During his year-and-a-half stay in the British Isles, the reverend secured funding from benefactors including Thomas Penn and Benjamin Franklin.

In 1770, the college moved from Warren to Providence. To establish a campus, John and Moses Brown purchased a four-acre lot on the crest of College Hill on behalf of the school. The majority of the property fell within the bounds of the original home lot of Chad Brown, an ancestor of the Browns and one of the original proprietors of Providence Plantations. After the college was relocated to the city, work began on constructing its first building.

A building committee, organized by the corporation, developed plans for the college’s first purpose-built edifice, finalizing a design on February 9, 1770. The subsequent structure, referred to as “The College Edifice” and later as University Hall, may have been modeled on Nassau Hall, built 14 years prior at the College of New Jersey. President Manning, an active member of the building process, was educated at Princeton and might have suggested that Brown’s first building resemble that of his alma mater.

The College

Founded in 1764, the college is Brown’s oldest school. About 7,200 undergraduate students are enrolled in the college, and 81 concentrations are offered. For the graduating class of 2020 the most popular concentrations were Computer Science; Economics; Biology; History; Applied Mathematics; International Relations and Political Science. A quarter of Brown undergraduates complete more than one concentration before graduating. If the existing programs do not align with their intended curricular interests, undergraduates may design and pursue independent concentrations.

35 percent of undergraduates pursue graduate or professional study immediately, 60 percent within 5 years, and 80 percent within 10 years. For the Class of 2009, 56 percent of all undergraduate alumni have since earned graduate degrees. Among undergraduate alumni who go on to receive graduate degrees, the most common degrees earned are J.D. (16%), M.D. (14%), M.A. (14%), M.Sc. (14%), and Ph.D. (11%). The most common institutions from which undergraduate alumni earn graduate degrees are Brown University, Columbia University, and Harvard University.

The highest fields of employment for undergraduate alumni ten years after graduation are education and higher education (15%), medicine (9%), business and finance (9%), law (8%), and computing and technology (7%).

Brown and RISD

Since its 1893 relocation to College Hill, Rhode Island School of Design (RISD) has bordered Brown to its west. Since 1900, Brown and RISD students have been able to cross-register at the two institutions, with Brown students permitted to take as many as four courses at RISD to count towards their Brown degree. The two institutions partner to provide various student-life services and the two student bodies compose a synergy in the College Hill cultural scene.

Rankings

Brown University is accredited by the New England Commission of Higher Education. For their 2021 rankings, The Wall Street Journal/Times Higher Education ranked Brown 5th in the Best Colleges 2021 edition.

The Forbes Magazine annual ranking of America’s Top Colleges 2021—which ranked 600 research universities, liberal arts colleges and service academies—ranked Brown 26th overall and 23rd among universities.

U.S. News & World Report ranked Brown 14th among national universities in its 2021 edition.[162] The 2021 edition also ranked Brown 1st for undergraduate teaching, 20th in Most Innovative Schools, and 18th in Best Value Schools.

Washington Monthly ranked Brown 37th in 2020 among 389 national universities in the U.S. based on its contribution to the public good, as measured by social mobility, research, and promoting public service.

For 2020, U.S. News & World Report ranks Brown 102nd globally.

In 2014, Forbes Magazine ranked Brown 7th on its list of “America’s Most Entrepreneurial Universities.” The Forbes analysis looked at the ratio of “alumni and students who have identified themselves as founders and business owners on LinkedIn” and the total number of alumni and students.

LinkedIn particularized the Forbes rankings, placing Brown third (between The Massachusetts Institute of Technology and Princeton University) among “Best Undergraduate Universities for Software Developers at Startups.” LinkedIn’s methodology involved a career-path examination of “millions of alumni profiles” in its membership database.

In 2020, U.S. News ranked Brown’s Warren Alpert Medical School the 9th most selective in the country, with an acceptance rate of 2.8 percent.

According to 2020 data from The Department of Education, the median starting salary of Brown computer science graduates was the highest in the United States.

In 2020, Brown produced the second-highest number of Fulbright winners. For the three years prior, the university produced the most Fulbright winners of any university in the nation.

Research

Brown is member of The Association of American Universities since 1933 and is classified among “R1: Doctoral Universities – Very High Research Activity”. In FY 2017, Brown spent $212.3 million on research and was ranked 103rd in the United States by total R&D expenditure by The National Science Foundation.

From Sky & Telescope : “Two Impacts-Not Just One-May Have Formed The Moon”

From Sky & Telescope

October 14, 2021
Asa Stahl

In this image, the proposed hit-and-run collision is simulated in 3D, shown about an hour after impact. Theia, the impactor, barely escapes the collision. A. Emsenhuber / The University of Bern [Universität Bern](CH) / The Ludwig Maximilians University of Munich [Ludwig-Maximilians-Universität München](DE).

Theia Protoplanet slamming into Earth-Sci-News.com

Scientists have long thought that the Moon formed with a bang, when a protoplanet the size of Mars hit the newborn Earth. Evidence from Moon rocks and simulations back up this idea.

But a new study suggests that the protoplanet most likely hit Earth twice. The first time, the impactor (dubbed “Theia”) only glanced off Earth. Then, some hundreds of thousands of years later, it came back to deliver the final blow.

The study, which simulated the literally Earth-shattering impact thousands of times, found that such a “hit-and-run return” scenario could help answer two longstanding questions surrounding the creation of the Moon. At the same time, it might explain how Earth and Venus ended up so different.

The One-Two Punch

“The key issue here is planetary diversity,” says Erik Asphaug (The University of Arizona (US)), who led the study. Venus and Earth have similar sizes, masses, and distances from the Sun. If Venus is a “crushing hot-house,” he asks, “why is Earth so amazingly blue and rich?”

The Moon might hold the secret. Its creation was the last major episode in Earth’s formation, a catastrophic event that set the stage for the rest of our planet’s evolution. “You can’t understand how Earth formed without understanding how the Moon formed,” Asphaug explains. “They are part of the same puzzle.”

The new simulations, which were published in the October Journal of Planetary Sciences, put a few more pieces of that puzzle into place.

The first has to do with the speed of Theia’s impact. If Theia had hit our planet too fast, it would have exploded into an interplanetary plume of debris and eroded much of Earth. Yet if it had come in too slowly, the result would be a Moon whose orbit looks nothing like what we see today. The original impact theory doesn’t explain why Theia traveled at a just-right speed between these extremes.

“[This] new scenario fixes that,” says Matthias Meier (Natural History Museum, Switzerland), who was not involved in the study. Initially, Theia could have been going much faster, but the first impact would have slowed it down to the perfect speed for the second one.

The other problem with the original impact theory is that our Moon ought to be mostly made of primordial Theia. But Moon rocks from the Apollo missions show that Earth and the Moon have nearly identical compositions when it comes to certain kinds of elements. How could they have formed from two different building blocks?

“The canonical giant-impact scenario is really bad at solving [this issue],” Meier says (though others have tried).

A hit-and-run return, on the other hand, would enable Earth’s and Theia’s materials to mix more than in a single impact, ultimately forming a Moon chemically more similar to Earth. Though Asphaug and colleagues don’t quite fix the mismatch, they argue that more advanced simulations would yield even better results.

Earth vs. Venus

Resolving this aspect of the giant-impact theory would be no mean feat. But Asphaug’s real surprise came when he saw how hit-and-run impacts would have affected Venus compared to Earth.

“I first thought maybe there was a mistake,” he recalls.

The new simulations showed that the young Earth tended to pass on half of its hit-and-runners to Venus, while Venus accreted almost everything that came its way. This dynamic could help explain the drastic differences between the two planets: If more runners ended up at Venus, they would have enriched the planet in more outer solar system material compared to Earth. And since the impactors that escaped Earth to go on to Venus would have been the faster ones, each planet would have experienced generally different collisions.

This finding flips the original purpose of the study on its head. If Venus suffered more giant impacts than Earth, the question would no longer be “why does Earth have a moon?” but “why doesn’t Venus?”

Perhaps there was only one hit-and-run event, the one that made our Moon. Perhaps there were many, but for the same reason that Venus collected more impacts than Earth, it also accreted more destructive debris, obliterating any moon it already had. Or perhaps the last of Venus’ impacts was just particularly violent.

Finding out means taking a trip to Venus. That would provide “the next leap in understanding,” Meier says. If Earth and Venus both had hit-and-runs, for example, then the surface of Venus ought to be more like Earth’s than previously expected. If Venus has the same chemical similarities as the Moon and Earth, that would throw out the giant-impact theory’s last remaining problem.

“Getting samples from Venus,” Asphaug concludes, “is the key to answering all these questions.”

See the full article here .

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Sky & Telescope, founded in 1941 by Charles A. Federer Jr. and Helen Spence Federer, has the largest, most experienced staff of any astronomy magazine in the world. Its editors are virtually all amateur or professional astronomers, and every one has built a telescope, written a book, done original research, developed a new product, or otherwise distinguished him or herself.

Sky & Telescope magazine, now in its eighth decade, came about because of some happy accidents. Its earliest known ancestor was a four-page bulletin called The Amateur Astronomer, which was begun in 1929 by the Amateur Astronomers Association in New York City. Then, in 1935, the American Museum of Natural History opened its Hayden Planetarium and began to issue a monthly bulletin that became a full-size magazine called The Sky within a year. Under the editorship of Hans Christian Adamson, The Sky featured large illustrations and articles from astronomers all over the globe. It immediately absorbed The Amateur Astronomer.

Despite initial success, by 1939 the planetarium found itself unable to continue financial support of The Sky. Charles A. Federer, who would become the dominant force behind Sky & Telescope, was then working as a lecturer at the planetarium. He was asked to take over publishing The Sky. Federer agreed and started an independent publishing corporation in New York.

“Our first issue came out in January 1940,” he noted. “We dropped from 32 to 24 pages, used cheaper quality paper…but editorially we further defined the departments and tried to squeeze as much information as possible between the covers.” Federer was The Sky’s editor, and his wife, Helen, served as managing editor. In that January 1940 issue, they stated their goal: “We shall try to make the magazine meet the needs of amateur astronomy, so that amateur astronomers will come to regard it as essential to their pursuit, and professionals to consider it a worthwhile medium in which to bring their work before the public.”

From Curtin University (AU) : “Curtin researchers help date the youngest rocks ever found on the Moon”

From Curtin University (AU)

8 October 2021

Yasmine Phillips
Media Relations Manager (Work days: Tuesdays, Wednesdays and Thursdays)
Tel: +61 8 9266 9085
Mob: +61 401 103 877
yasmine.phillips@curtin.edu.au

Vanessa Beasley
Deputy Director
Tel: +61 8 9266 1811
Mob: +61 466 853 121
vanessa.beasley@curtin.edu.au

Curtin University researchers have helped to determine the age of the youngest rocks ever found on the Moon, as part of a global space mission that is working to refine the chronology of the entire Solar System.

China’s Chang’e-5 Moon landing in December 2020. Source: China National Space Administration [国家航天局](CN) Lunar Exploration and Space Engineering Center.

The new research, published in Science, determined the basaltic volcanic rocks, collected as part of China’s Chang’e-5 Moon landing in December 2020, were about two billion years old – or one billion years younger than those previously found on the Moon.

The rock samples were collected by the Chinese National Space Agency during the Chang’e-5 mission, which marked the first time any nation had collected rocks from the Moon since 1976.

Lead Australian author Professor Alexander Nemchin, from Curtin University’s Space Science and Technology Centre in the School of Earth and Planetary Sciences, said researchers determined the age of the lunar rock samples during remote sessions with the Beijing laboratory using large mass spectrometers that have helped revolutionise geology, similar to Curtin’s Sensitive High Resolution Ion Micro Probe Facility (SHRIMP).

“Previously, the youngest lunar basalt rocks collected as part of the Apollo and Luna missions, as well as lunar meteorites, were found to be older than about three billion years,” Professor Nemchin said.

“After analysing the chemistry of the new Moon rocks collected as part of China’s recent mission, we determined the new samples were about two billion years old, making them the youngest volcanic rocks identified on the Moon so far.

“This discovery puts Australia at the heart of efforts to internationalise scientific collaboration around China’s lunar exploration program, including samples returned from China’s Chang’e-5 mission and the upcoming Chang’e-6 Moon landing in 2024.”

Co-author Professor Gretchen Benedix, also from Curtin’s Space Science and Technology Centre, said the new results would provide researchers with more calibration points for cratering chronology, enabling them to derive more accurate and higher resolution ages across many planetary surfaces.

“These results confirm what experts had long predicted based on remotely obtained images of the Moon and raise further questions as to why these young basalts exist,” Professor Benedix said.

“The task will now turn to finding a mechanism that will explain how this relatively recent heating of the Moon may have supported the formation of basaltic magmas with temperatures exceeding 1000 degrees Celsius – and ultimately help researchers improve age dating of the entire Solar System.”

Professor Fred Jourdan from Curtin’s School of Earth and Planetary Sciences was also a co-author of this paper.

The research was carried out in collaboration with experts from the International Lunar and Planetary Research Center of China, The Beijing SHRIMP Center, The Australian National University, Washington University in St Louis, Notre Dame University and Brown University in the United States of America, the University of Colorado, Manchester University in the United Kingdom and the Natural History Museum in Sweden.

See the full article here .

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Please help promote STEM in your local schools.

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Curtin University (AU) (formerly known as Curtin University of Technology and Western Australian Institute of Technology) is an Australian public research university based in Bentley and Perth, Western Australia. The university is named after the 14th Prime Minister of Australia, John Curtin, and is the largest university in Western Australia, with over 58,000 students (as of 2016).

Curtin would like to pay respect to the indigenous members of our community by acknowledging the traditional owners of the land on which the Perth campus is located, the Wadjuk people of the Nyungar Nation; and on our Kalgoorlie campus, the Wongutha people of the North-Eastern Goldfields.

Curtin was conferred university status after legislation was passed by the Parliament of Western Australia in 1986. Since then, the university has been expanding its presence and has campuses in Singapore, Malaysia, Dubai and Mauritius. It has ties with 90 exchange universities in 20 countries. The University comprises five main faculties with over 95 specialists centres. The University formerly had a Sydney campus between 2005 & 2016. On 17 September 2015, Curtin University Council made a decision to close its Sydney campus by early 2017.

Curtin University is a member of Australian Technology Network (ATN), and is active in research in a range of academic and practical fields, including Resources and Energy (e.g., petroleum gas), Information and Communication, Health, Ageing and Well-being (Public Health), Communities and Changing Environments, Growth and Prosperity and Creative Writing.

It is the only Western Australian university to produce a PhD recipient of the AINSE gold medal, which is the highest recognition for PhD-level research excellence in Australia and New Zealand.

Curtin has become active in research and partnerships overseas, particularly in mainland China. It is involved in a number of business, management, and research projects, particularly in supercomputing, where the university participates in a tri-continental array with nodes in Perth, Beijing, and Edinburgh. Western Australia has become an important exporter of minerals, petroleum and natural gas. The Chinese Premier Wen Jiabao visited the Woodside-funded hydrocarbon research facility during his visit to Australia in 2005.

From Caltech: “Caltech-Led Lunar Trailblazer Mission Approved to Begin Final Design and Build”

From Caltech

December 02, 2020

Written by
Lori Dajose

Contact
Robert Perkins
(626) 395‑1862
rperkins@caltech.edu

After one year of preliminary design and several reviews, NASA has confirmed the Caltech-led Lunar Trailblazer mission to proceed to final design and build. Selected in June 2019 with planned flight system delivery in October 2022, the Lunar Trailblazer mission targets one of the most surprising discoveries of the decade: the presence of water on the Moon.

In this webinar presented by the Keck Institute for Space Studies, Caltech professor of planetary science Bethany Ehlmann presents the Lunar Trailblazer mission design and objectives. Credit: KISS/Caltech.
1:02:15

The mission is a collaboration led by principal investigator Bethany Ehlmann, Caltech professor of planetary science, and managed by JPL, which Caltech manages for NASA.

NASA JPL

Other key partners include spacecraft provider Lockheed Martin and the University of Oxford (UK), which provides one of Lunar Trailblazer’s two instruments.

“We’re excited to pioneer NASA’s use of small satellites to answer big planetary science questions,” says Ehlmann. “We expect Trailblazer will hugely advance our understanding of something we don’t fully understand: the water cycle on airless bodies. Given the importance of water on the Moon for future robotic and human missions, the Lunar Trailblazer mission team is excited to provide the critical basemaps that will guide this future exploration.”

The relatively tiny Trailblazer satellite, which will measure just 3.5 meters in length with its solar panels fully deployed, will spend over a year orbiting the Moon at a height of 100 kilometers, scanning it with two instruments: a visible-shortwave infrared imaging spectrometer built by JPL and a multispectral thermal imager built by the University of Oxford. These instruments will determine the amount and form of water on the Moon, which is not liquid but instead occurs as water ice in cold regions, as free molecules, or bound within minerals. As a NASA SIMPLEx (Small Innovative Missions for Planetary Exploration) program selection, Lunar Trailblazer achieves critical advancements for science as a lower-budget, ride-along mission.

“Lunar Trailblazer has a talented, multi-institutional team whose collective effort resulted in a successful formulation phase and confirmation review,” says Calina Seybold, the mission’s project manager at JPL. “I am thrilled that the team has earned the privilege of continuing to our final design and fabrication phase.”

A key partnership is with Lockheed Martin Space, based out of Denver, Colorado, which will design, integrate, and test the Lunar Trailblazer spacecraft. The company brings its expertise from another SIMPLEx mission called Janus, which will explore asteroids, as well as decades of planetary missions across the solar system.

Joshua Wood, Lunar Trailblazer spacecraft manager at Lockheed Martin, says he is excited for what lies ahead: “Passing this key decision point means we have the green flag to proceed with production on the spacecraft. I’m very excited to see all the big science this compact spacecraft will surely bring back to us.”

A key feature of Lunar Trailblazer is the large role for Caltech in executing the mission. In addition to Ehlmann’s leadership as PI, co-investigator James Dickson, manager of the Bruce Murray Laboratory for Planetary Visualization, will direct the science data system. Mission operations will be run out of Caltech’s IPAC, which brings long experience with space telescope science operations. Through a NASA-funded Student Collaboration Option, undergraduates from Caltech and nearby Pasadena City College are participating in mission communications and mission development, and will help staff operations. In addition to JPL, Lockheed Martin, University of Oxford (UK), and PCC, the other key mission partners are the Applied Physics Laboratory, Brown University, Northern Arizona University, and the University of Central Florida.

“Some of the big questions about water on the Moon are: Does it vary as a function of time of day and temperature? Is it bound in rock or mobile? Why do some shadowed regions host water ice while others are empty, and how much is there at the lunar surface?” says Ehlmann. “We look forward to answering these questions with Lunar Trailblazer.”

Learn more about the mission objectives, instruments, and team here: https://trailblazer.caltech.edu/

See the full article here .

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Please help promote STEM in your local schools.

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The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

Caltech campus

From Curiosity: “The Apollo 12 Mission Had a Curious Claim of Bacterial Life”

Curiosity Makes You Smarter

From From Curiosity

December 20, 2019
Elizabeth Howell

View, during NASA’s Apollo 12 mission, of the ‘Intrepid’ Lunar Module as it descends to the surface of the moon, November 19, 1969.
Interim Archives—Getty Images

Pieces of a craft that spent two years on the moon in the 1960s turned out to harbor something unexpected: bacteria. Did microbes successfully stow away for a moon mission and survive their return to Earth, or were they introduced during later testing? That’s one of the mysteries surrounding the Apollo 12 mission, which brought pieces of the Surveyor 3 robot back to Earth 50 years ago. Here are the latest theories about what happened.

Surviving Space?

The story begins with Apollo 12 astronaut Pete Conrad making a remarkable pinpoint landing on the Ocean of Storms in November 1969, fulfilling the mission objective to land within walking distance of the Surveyor 3 spacecraft that landed two years beforehand. Engineers were curious about how radiation in space might change a spacecraft over time, which is important if you want to design a durable spacecraft.

Astronauts Conrad and Alan Bean dutifully returned some pieces of Surveyor 3 back to Earth — the TV camera, some electrical cables, a sample scoop, and two pieces of aluminum tubing, according to NASA. What some scientists found in those samples has been the subject of Internet rumors ever since.

One research group recovered a little bit of the bacterium Streptococcus mitis, a harmless microorganism that lives in the human nose, throat, and mouth, in some foam within Surveyor 3’s newly returned camera. Surveyor 3 hadn’t been sterilized before going to the moon, and this research group supposed that microbes in the foam had survived the launch, the vacuum of space, and three years on the moon without any source for continuing life, such as water or nutrients. But there’s another explanation that you should consider first.

NASA

Earthly Contamination?

We’ve learned a lot about microbiology and about protecting spacecraft in the last 50 years, and the standards we use today are a lot higher than at the end of the 1960s. For example, the camera came back in a nylon duffel bag that was not airtight, unlike the lunar samples themselves.

“Some people associated with the curation of the Surveyor 3 materials have suggested that the one positive detection of life may be the result of accidental contamination of the material after it was returned to Earth,” NASA said in a statement on the experiment. And there are other explanations, too, including that perhaps the researchers had a false-positive result — that is, maybe they’d incorrectly detected microbes that weren’t actually there.

NASA noted another thing that probably would not be done today: “One of the implements being used to scrape samples off the Surveyor parts could have been laid down on a non-sterile laboratory bench, and then was used to collect surface samples for culturing. It is, therefore, quite possible that the microorganisms were transferred to the camera after its return to Earth.”

NASA

So what’s the verdict between the microbes surviving space for three years, or transferring through simple contamination? It’s hard to say for sure because we can’t repeat the experiment. However, the scientific community is leaning more towards the contamination hypothesis, according to a 2008 statement from one of NASA’s institutes. This hypothesis was also supported in a 2011 conference presentation with a team that included a NASA scientist. The agency tries to take it as a lesson learned when it prepares for missions to places like Mars. The Mars 2020 rover is being designed to search for signs of ancient life, and NASA needs to take every precaution to ensure any life they find is truly Martian.

Today, you can see the very camera that harbored these microbes at the Smithsonian Institution — a popular location for many space artifacts. The microbe mystery is a fun history lesson to consider and teaches us the importance of always checking claims carefully before accepting them at face value.

Surveyor III Television Camera
The television camera from the Surveyor III spacecraft was removed from Surveyor, about two-and-a-half years after the spacecraft landed, by the crew of Apollo 12 and returned to Earth. Smithsonian Ait and Space Museum

See the full article here .

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From AGU GeoSpace Blog: “Ancient Moon rock provides evidence of giant lunar impact 4.3 billion years ago”

From From AGU GeoSpace Blog

16 October 2019
Abigail Eisenstadt

Clast 3A refers to the area sampled from the anorthosite rock called 60016. The rock shown here was brought back during the Apollo 16 mission.
Credit: AGU.

An Apollo 16 lunar rock sample shows evidence of intense meteorite bombardment on the Moon 4.3 billion years ago, according to new research. The results provide new insights for the Moon’s early history, showing lunar impacts were common throughout the Moon’s formation than previously thought.

When the Moon first formed, its surface was covered in a sea of molten rock called the lunar magma ocean. This magma ocean eventually cooled and formed the rocks that make up the lunar crust and mantle.

A new study in AGU’s Journal of Geophysical Research: Planets analyzed a Moon rock from the Apollo 16 mission and found the rock cooled quicker than expected. The results suggest that 4.3 billion years ago a previously unidentified impact event forced the rock from the depths of the slowly cooling lunar crust to the surface.

“Something hit the Moon while the rocks were still at high temperatures, excavated the rock from depths in the lunar crust, and then it cooled quickly after that,” said Naomi Marks, a geochemist at Lawrence Livermore National Laboratory in Livermore, California and lead author of the new study.

Many planetary scientists had previously accepted the idea that the Moon had a relatively peaceful existence following its creation until the Late Heavy Bombardment, a period when the Moon was intensely pelted by meteorites and asteroids 4.0 billion to 3.8 billion years ago. But scientists have been questioning the accuracy of this theory. The new results add to growing evidence that the theory may be incorrect by identifying a major impact outside of the theory’s timeframe, according to the study’s authors.

“We are fairly confident that that the age is recording an impact, which means that there were significant impacts outside of the Late Heavy Bombardment period,” Marks said.

Understanding ancient lunar impacts could help scientists uncover more information about the early Moon’s formation and its surroundings.

Forming rocks from magma

The Moon is thought to have originated from debris created by a collision between an ancient Mars-sized planet and Earth. During its initial period of formation, the Moon’s surface was an ocean of magma. Eventually, heavier elements began to sink to the depths of the ocean, forming the solid lunar core around 4.4 billion years ago. Then the outer layer comprised of lighter material began to rise to the top and cool. This formation of the lunar crust is estimated to have taken between 10 million and 250 million years.

Studying the lunar crust allows scientists to learn more about the Moon’s origins and evolution. One type of lunar surface rock, called anorthosites, are responsible for the Moon’s bright white color and were once thought to be the oldest rocks on the lunar surface.

In the new study, Marks and her colleagues wanted to use anorthosites to estimate how long it took for the lunar magma ocean to cool and solidify into rocks. They took a sample from a previously unexamined anorthosite collected by the Apollo 16 mission and analyzed isotopes produced by the radioactive decay of elements within the rock to determine when it cooled to certain temperatures.

They found the rock went from around 855 degrees Celsius (1,571 degrees Fahrenheit) to roughly 250 degrees Celsius (482 degrees Fahrenheit) within a few thousand years – an unusually quick cooling rate in the scheme of other planetary timescales. The rapid cooling indicates a major impact likely propelled rock out of the lower crust to the surface, where it rapidly cooled into anorthosite alongside other rocks, according to the authors.

The study provides good evidence for a large impact on the Moon 4.3 billion year ago, adding to many decades of research on lunar chronology, said Kevin McKeegan, a planetary scientist at the University of California, Los Angeles in Los Angeles, California, who was unaffiliated with the study.

Evidence for the ancient lunar impact reveals how tumultuous the Moon’s early period was, helping scientists understand more about its formation and composition, according to Marks.

See the full article here .

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GeoSpace is a blog on Earth and space science, managed by AGU’s Public Information staff. The blog features posts by AGU writers and guest contributors on all sorts of relevant science topics, but with a focus on new research and geo and space sciences-related stories that are currently in the news.

Do you have ideas on topics we should be covering? Would you like to contribute a guest post to the blog? Contact Peter Weiss at pweiss@agu.org.