News and Updates
In the beginning, all was hydrogen – and helium, plus a bit of lithium. Three elements in all. Today's universe, however, has nearly a hundred naturally occurring elements, with thousands of variants (isotopes), and more likely to come.
Figuring out how the universe got from its starting batch of three elements to the menagerie found today is the focus of a new Physics Frontiers Center research grant to Arizona State University's School of Earth and Space Exploration (SESE). The grant is from the National Science Foundation's Joint Institute for Nuclear Astrophysics – Center for the Evolution of the Elements. Of the full $11.4 million NSF grant, about $1 million will come to ASU over five years.
SESE astrophysicist Frank Timmes is the lead scientist for ASU's part of the Physics Frontiers Center research project. Timmes, ASU's director of advanced computing, focuses his astrophysical research on supernovae, cosmic chemical evolution, their impacts on astrobiology and high-performance computing. He is also a scientific editor of The Astrophysical Journal.
The evolution of elements project also includes Michigan State University in Lansing (the lead institution), the University of Notre Dame in South Bend, Indiana, and the University of Washington in Seattle.
Joining Timmes on the project will be astrophysicists Patrick Young, Evan Scannapieco and Sumner Starrfield, also from the School of Earth and Space Exploration In addition, the award will fund two postdoctoral researchers to collaborate on the effort.
Take it from the top
Time started 13.7 billion years ago with the Big Bang, which produced the basic three elements. Yet by the time the Bang was a billion years old, essentially all the other chemical elements we know had formed. How did this happen?
"It takes place inside stars," says Timmes. "They're the element-factories of the universe. They take light stuff, such as hydrogen and helium, process it in nuclear reactions, and then crank out carbon, nitrogen, oxygen and all those good things that make you and me."
While the broad outline is clear, details are a lot murkier, he says, and that's where ASU's researchers enter the picture.
"ASU's contribution is to provide the glue between experimental low-energy nuclear astrophysics measurements and astronomical observations of stars," Timmes says.
Ancient stars were fundamentally different from those today, he notes, because they started off with a different collection of initial ingredients – no heavy elements. But those first-generation stars are gone.
As Timmes explains, "The stars that began back then went through their life cycles and died, so we naturally don't directly see them today. But when they died, they exploded and threw out little bits of carbon, oxygen and nitrogen, which ended up in the next generation of stars."
Round and round in cycles
In a process that still continues today, massive stars create more and more complex elements, then explode as supernovas and scatter the newly created elements into space for another generation of stars to use. Cycle after stellar cycle, stars became steadily richer in heavier and more complex elements.
The sun, its planets and moons all formed about 4.5 billion years ago. Most of the elements they contain didn't exist when the universe was young, so what generation does the sun belong to?
Timmes explains, "A typical massive star, in round numbers, lives about a million years. The Big Bang occurred about 7 billion years before the sun formed. I need a thousand generations of massive stars to get us to a billion years, so I need on the order of 10,000 generations of massive stars to get one with the sun's composition.
"We are the product of many, many, many previous generations of stars."
The researchers at the School of Earth and Space Exploration plan to develop computer models of stars of all sizes, masses and chemical compositions, then set them on their life courses. It's building stars in computers and comparing them to observations of stars to see how the universe builds them for real.
"The toughest theoretical problem we have to work on is how stars explode," says Timmes. "In a loose, hand-waving sense, we know that stars explode, of course, but exactly how it happens isn't well-known or understood."
The new research project fits well with the expertise of the school's astrophysicists. And there's another plus as well. With this project, ASU is joining a small group of research centers that deal with "Frontiers Physics." The entire country has only about ten such centers, Timmes explains. Highly competitive and highly sought-after, they cover subjects such as biological physics and theoretical physics.
But there's just one nuclear astrophysics center, he says. "And it's great that ASU is going to play a key role in it."
It might seem like a good idea to prevent people from building on land where active earthquake faults run. But experience in California with just such a land-use law, enacted in 1972, shows it's having unintended effects.
Some of those strips of hazardous land have become greenbelts that attract high-value homes and wealthy people, according to a study published in the journal Earth's Future and mentioned in KQED's Science blog.
"We were astonished to discover the correlation between fault-zone parks and greenways – and high-priced housing," says Ramon Arrowsmith, professor of geology in Arizona State University's School of Earth and Space Exploration (SESE). He is a co-author of the study, along with Christopher Boone from ASU's School of Sustainability and Nathan Toké from Utah Valley University, Orem, the lead author of the study. (Toké received his PhD from SESE in 2011.)
The researchers anticipated that the areas next to active fault zones would have become stigmatized and avoided by wealthy people. The team expected to find them occupied mostly by poor and socially vulnerable populations.
In fact, the opposite happened for the most part. Removing areas from the possibility of new construction led developers to build additional park space adjacent to the hazard zones. Parks and greenspace are seen as environmental amenities, and this made them more desirable, despite the known seismic risks. This was especially true in the parks-poor city of Los Angeles.
Transforming zones of natural hazard into amenities attracted populations of relatively high social status. The team concluded that the distribution of social vulnerability is sometimes more strongly tied to amenities than to hazards.
Arrowsmith says, "I was surprised with the unintended consequences of the hazard maps. These actually produced attractive greenbelts and open space, and thus higher value real estate and associated demographic implications."
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7 pm - 10 pm
Saturday, Sept. 6 is International Observe the Moon Night all over the world. In celebration, lunar scientists and researchers at Arizona State University's School of Earth and Space Exploration are holding an open house for the public dedicated to the Moon and Moon-observing.
The open house will run from 7-10 p.m., Sept. 6 (regardless of the weather) at the Lunar Reconnaissance Orbiter Camera Science Operations Center on ASU's Tempe campus. The center is located in Interdisciplinary Building A-wing, 1100 S. Cady Mall. Parking is available in the Apache Boulevard Parking Structure and on the street.
The public is invited to observe the Moon through telescopes, through stunning images from NASA's Lunar Reconnaissance Orbiter and through the eyes of scientists who have studied our neighbor world in detail.
At the open house, you will be able to:
• View the Moon through telescopes
• Examine detailed images of the Moon's surface taken by the LRO spacecraft
• Tour the Science Operations Center
• Ask scientists questions about the Moon and lunar exploration
• Participate in a scavenger hunt
• View an actual rock from the Moon, collected by Apollo 15 astronauts
Don't miss this great opportunity to explore the Moon with your own eyes through a telescope.
In July 1978, Peter Buseck of Arizona State University, together with two postdoctoral researchers (also then at ASU), published a paper on a new technique for high-resolution imaging of crystal structures using transmission electron microscopes. Recently, the scientific journalNature has hailed that paper as a milestone in the science of crystallography. At the same time, Nature also cited three other milestone crystallography papers.
The Nature Milestones series highlights key discoveries that have shaped different scientific fields, and enables the wider recognition of classic findings that are often recognized only by those in the field.
Buseck, an ASU Regents' Professor in both the School of Earth and Space Exploration and the Department of Chemistry and Biochemistry, notes today, "We used a relatively common mineral, vesuvianite, as an example because it has a complex crystal structure. The paper showed how quantitative structural information down to almost the atomic level could be obtained by careful electron microscopy and electron diffraction."
Both of the then-postdocs have gone on to distinguished careers, he notes. Michael O'Keefe spent most of his career at the National Center for Electron Microscopy in Berkeley, California. He is a former president of the Microscopy Society of America, and has had many successes in theoretical electron microscopy.
The other postdoctoral researcher, Sumio Iijima, is the discoverer of carbon nanotubes. Notes Buseck, "He has had a highly distinguished career working on surface microscopy, catalysts and other advanced materials."
Iijima is a past president of the Japanese Microscopy Society, a member of the Japanese Academy and U.S. National Academy of Sciences, among others. His many prizes include the the Benjamin Franklin Medal in physics from The Franklin Institute (2002) and the inaugural Kavli Prize for Nanoscience (Kavli Foundation, Norway, 2008).
"It's an unanticipated but pleasant surprise that this paper would be cited as a milestone contribution 36 years after publication," says Buseck today.
"At the time, my students and postdoctoral associates were using transmission electron microscopy in new ways to study various aspects of minerals. Our papers were appearing regularly in Nature and Science, and the cited paper did not seem more or less special than many of the others. Nonetheless, its selection is gratifying."
Editor's Note: Links are included for informational purposes only. Due to varying editorial policies, news publications may remove or change a link for archival purposes at any time without notice.
New lunar meteorite to be on display at ASU’s Center for Meteorite Studies
Arizona State University’s Center for Meteorite Studies (CMS) recently received a precious gift. Aside from its price tag, what makes this space rock so special is where it came from: the Moon.
The new sample belongs to the rare class of meteorites originating from the Moon called “lunaites”. Of all known distinct meteorites in this world, of which there are tens of thousands, less than a hundred are thought to come from the Moon.
The softball-size meteorite donation is valued at about a quarter of a million dollars, and is likely to be the most significant single donation ever made to the Center.
“Of the tens of thousands of known meteorites (most of which come from asteroids), only a very tiny fraction are lunaites. So this is a very rare kind even among meteorites, which are themselves quite rare among rocks found on Earth,” says Meenakshi Wadhwa, director of the Center and professor in ASU’s School of Earth and Space Exploration. “This new sample is probably one of our most prized pieces and without a doubt one of the most significant recent additions to our collection.”
Known as Northwest Africa 7611, this meteorite was found near the Moroccan/Algerian border in May 2012. It was subsequently purchased by the donor, Dr. Jay Piatek, from a Moroccan meteorite dealer. Piatek is an avid meteorite collector and owns one of the more significant private collections in the world. He is a supporter and generous donor to university and museum collections.
The Center has six other lunaites in its collection, but their total weight is about 60 grams. As such, this new lunaite, weighing 311 grams, represents a five-fold increase in the total mass of lunar material in the collection. The total known weight of the original specimen was 916 grams, and the mass donated to the Center is the largest remaining mass (or main mass) of this meteorite.
“The chemistry, mineralogy and textures of lunar meteorites or lunaites are similar to samples that were brought back from the Moon by the Apollo missions (1969-1972). These characteristics are quite distinct from other classes of meteorites and terrestrial rocks,” explains Wadhwa. “Lunaites can have a small amount of metal, but it is present in very small abundance compared to ordinary chondrites, for example, which are the most common types of meteorites.”
Classified as a lunar regolith breccia, this meteorite contains a mix of rock types from the Moon’s mare and highlands. However, because there is very little mare material on the far-side of the Moon, this regolith breccia most likely came from the near-side (that has both mare and highlands material).
The gift will be on display for the short term, but there are plans to use it for research purposes in the future years.
“It is a beautiful fresh-looking piece, with one cut and polished face that shows the internal texture and fabric of the rock – as such it displays a unique snapshot of the lunar surface,” says CMS collections manager Laurence Garvie.
Consisting of specimens from around 2,000 separate meteorite falls and finds, meteorites in the Center’s collection represent samples collected from every part of the world. Visitors may explore the collection weekdays, from 8 a.m. to 5 p.m., on the second floor of Interdisciplinary Science and Technology Building IV.
Photo Photo of the spectacular 311 gram lunar meteorite (NWA 7611) on display in ASU’s Center for Meteorite Studies. The cut and polished surface uniquely shows the great diversity of rock types on the lunar surface. Photo by Laurence Garvie
To welcome this year’s incoming freshmen, the School of Earth and Space Exploration (SESE) and the Center for Meteorite Studies at Arizona State University have dedicated a meteorite to the Class of 2018.
Meteorites are remnants of processes that occurred in the earliest history of the Solar System ~4.5 billion years ago.
The Class of 2018’s meteorite, a 381 gram slice of the Seymchan pallasite, was found in Russia in 1967. It is a stony-iron meteorite (pallasite) composed mostly of nickel-rich iron metal and olivine (a yellowish-green silicate mineral). It is thought to have formed at the core-mantle boundary of an asteroid that later broke apart such that pieces then fell to Earth as meteorites.
“This meteorite was obtained especially for the purpose of dedicating to, and inspiring, the Class of 2018,” says Professor Meenakshi Wadhwa, director of the Center for Meteorite Studies. “We wanted to give them a unique gift, something memorable – so this exceptional meteorite specimen seemed like the perfect fit.”
Incoming freshmen are encouraged to visit “their” meteorite, located in the lobby of the Interdisciplinary Science and Technology Building IV (ISTB 4), part of the Gallery of Scientific Exploration.
The Center for Meteorite Studies in SESE houses the largest, most significant university-based collection of these unique materials. The Meteorite Gallery is located on the second floor of ISTB 4. The display is open to the public for self-guided tours Monday through Friday, from 9 a.m. to 5 p.m., excluding ASU holidays.
You may want to tune in for this:
SESE’s Sara Walker will be on NPR's Science Friday discussing the novel Dune on 8/22 for the Science Friday Bookclub. She will be on air 11:40-noon (AZ time).
An Arizona State University alumna has devised the largest catalog ever produced for stellar compositions. Called the Hypatia Catalog, after one of the first female astronomers who lived ~350 AD in Alexandria, the work is critical to understanding the properties of stars, how they form, and possible connections with the formation and habitability of orbiting planets. And what she found from her work is that the compositions of nearby stars aren’t as uniform as once thought.
Since it is not possible to physically sample a star to determine its composition, astronomers study of the light from the object. This is known as spectroscopy, and it is one of the most important tools that an astronomer has for studying the universe. From it, researchers can often get information about the temperature, density, composition, and important physical processes of an astronomical object.
The digital catalog is a compilation of spectroscopic abundance data from 84 literature sources for 50 elements across 3,058 stars in the solar neighborhood, within 500 lightyears of the Sun. It essentially lists the compositions of stars, but only stars that are like the Sun – or F-, G-, or K-type (the Sun is a G-type star) – that are relatively near to the Sun.
“This catalog can hopefully be used to guide a better understanding of how the local neighborhood has evolved,” explains Natalie Hinkel, who graduated from ASU in 2012 with her doctorate in astrophysics and is now a postdoctoral fellow at San Francisco State University (SFSU).
Putting together a catalog this large that is an accumulation of other people’s work required a substantial amount of background research – compiling the first 50 datasets took her about six months. In total, and with the help of her collaborators Frank Timmes, Patrick Young, Michael Pagano, and Maggie Turnbull, the project took about two years. Hinkel started the project as her dissertation at ASU; however, a significant number of changes and revisions were made to the published manuscript while Hinkel was a postdoctoral researcher at San Francisco State University.
Vizier, a database where researchers can post their astronomical data, was a starting point but since not everyone posts their data online, many times Hinkel had to go to individual papers and transcribe the data by hand.
The Hypatia Catalog has a wide number of applications. The most obvious one for astronomers is looking at stars who host extrasolar planets, or exoplanets.
“Since 1997, we’ve known that stars with giant, Jupiter-like planets have quite a bit of iron in them. This result has been reproduced dozens of times. However, with a catalog of this magnitude, we can now study literally all of the other elements measured in stars in great detail to see if there are relationships between the presence of a planet (gaseous or terrestrial) and the element abundances,” explains Hinkel.
“Hypatia will help guide the future search for habitable planets as we learn to predict the properties of planets from the elemental makeup of the stars they orbit,” says ASU President’s Professor Ariel Anbar, who oversees the ASU Astrobiology Program. The work on the Hypatia Catalog was an outcome of the NASA Astrobiology Institute’s program at ASU.
Co-author Young, an associate professor in ASU’s School of Earth and Space Exploration, believes that “this is a great step forward in our understanding of the chemical compositions of stars, which fundamentally affect their evolution and the properties of the planets that accompany them.”
“Given all of the motion in the galaxy, this was a very unexpected result. But it’s also very exciting because of the huge number of implications for nearby planets, their compositions, and whether they could be habitable - by us or something similar to us,” says Hinkel.
While constructing the catalog, Hinkel noticed that the stars in the solar neighborhood reveal unexpected compositions, which is discussed in the paper published in the September issue of the Astronomical Journal.
The Sun is in the disk of the galaxy, where the vast majority of the Milky Way’s young stars are located. As the disk rotates, so too do the stars – both in the direction of the disk, as well as in smaller random motions.
“You can think of this like a swarm of bees: While the swarm in general moves, the bees themselves are going in all different directions. Because of this motion within the disk, the stars are considered to be well mixed – like a tossed salad. Therefore, you don’t expect to see, for example, a whole tomato in your salad – or many stars that have similar abundances in close proximity to each other,” explains Hinkel.
However, what Hinkel found is that the nearby ‘solar salad’ is comprised of lettuce at the bottom, chunks of tomato in the middle (where the middle of the galactic plane is), then lettuce again on top. In this case, the lettuce are stars that all have a high abundances of quite a few elements and the tomatoes are stars that have low abundances of those same elements.
In other words, the solar neighborhood does not appear to be a mixed salad; it’s a layered salad.
The full catalog will be available via Hinkel’s paper through the Astronomical Journal. The analyzed, reduced version will be made available through Vizier (http://vizier.u-strasbg.fr/viz-bin/VizieR), which anyone is free to access.
Photo: Natalie Hinkel gives a plenary talk at the Cool Stars 18 meeting in Flagstaff, Ariz. about her paper on the Hypatia Catalog. Courtesy Natalie Hinkel
The search for extraterrestrial life, popularly known as SETI, has traditionally focused on searching for life in the universe by scanning the skies for electromagnetic radiation, like radio waves. A better way to search for extraterrestrial civilizations might be to look for industrial pollution, argues Sara Imari Walker, an assistant professor in ASU's School of Earth and Space Exploration and the Beyond Center for Fundamental Concepts in Science, in a Future Tense article for Slate magazine.
Industrial pollutants like the climate-altering chlorofluorocarbons (CFCs) that human industries produce could potentially be detected from hundreds of light years away. Pollution may be a more reliable sign of advanced civilizations than radio waves, which, judging by our own technological development, are only a temporary stepping stone to more advanced communications technology.
The Earth, which once broadcast a high volume of radio waves into space, is becoming increasingly "radio quiet" as we shift toward digital communications. If extraterrestrial civilizations are like us, they will only be using radio waves for 100 years or so, which seems like a long time, but on a cosmic scale is "hardly the blink of an eye."
Henry Lin of the Harvard-Smithsonian Center for Astrophysics, which has led the way in championing the hunt-for-pollution approach, has questioned whether discovering pollution in the farthest reaches of space would really be a sign of intelligent life.
Lin wonders if "civilizations more advanced than us ... will consider pollution as a sign of unintelligent life since it's not smart to contaminate your own air." Walker's perspective is that "our methods to search for extraterrestrial intelligence are an intimate reflection of ourselves."
In a historical moment where pollution and climate change are in the forefront of our global consciousness, it's not such a surprise that we are searching the skies for other civilizations in a similar situation.
"Hopefully," writes Walker, "we will one day enter a phase of human technological development where we will possess the insights to look for 'greener' little green men."
To learn more about pollution and the search for extraterrestrial intelligence, including hunting for alien garbage on the moon, read the full article at Future Tense.
Future Tense is a collaboration among ASU, the New America Foundation and Slate magazine that explores how emerging technologies affect policy and society.
Image: SETI has traditionally focused on looking for signs of life by scanning the skies for electromagnetic radiation. Above, a false-color view constructed using infrared data from the Spitzer Space Telescope of the Orion Nebula. Photo by: NASA/JPL-Caltech