ASU News - Earth / Space

Sally Ride blasts onto Tempe campus for festival

icsea — Mon, 25 Feb 2008 16:20:48 -0700

Sally Ride, America’s first woman in space, returns to ASU on March 1 as keynote speaker for the Sally Ride Science Festival and Educator Institute. About 800 to 1,000 children, teachers and parents are expected to attend the events, which will cover topics like exploding stars, extreme astronomy and molecular madness.

This is the seventh year for the festival to be held at ASU, with interactive presentations taking place from 11 a.m. to 4 p.m. at Gammage Auditorium. The aim is to spark fifth through eighth graders’ interests in science, math and technology, with discovery workshops and a street fair that includes hands-on activities, booths, food and music.

Co-sponsors are Barrett, the Honors College, and Sally Ride Science, a science content company for children that also produces publications, summer camps and after-school programs.

A professional development workshop for teachers will take place at the same time at the Mars Space Flight Facility, called “From Astrobiology to Zoology: Igniting Students’ Interest in Science Careers.” Teachers will learn practical ways to integrate science careers into their classroom activities and will be given time to customize lessons and activities for their classrooms.

The festival costs $18 and the educator institute costs $30, including lunch, workshops and the featured talk. Advance registration is required, with a deadline of Feb. 29. For information or registration go to www.sallyridescience.com/festivals or call 800-516-5161.

Children’s workshops will be taught by local scientists and engineers, with ASU faculty and students taking the lead. Participants will include Cecilia Lunardini of physics, Frank Timmes and Laura Wasylenki of the School of Earth and Space Exploration, Gregory Privitera of psychology, Marcia Levitus of Biodesign, and Libby Larson of geography, along with a dozen graduate and undergraduate students.

Irene Bradley, admissions specialist, will talk to parents and teachers about preparing young students for college. Anita Verdugo Tarango, director of outreach for University Student Initiatives, will discuss the Barrett Summer Scholars program.

Hunter of dinosaur mystery to address scientific revolutions

chughes3 — Mon, 18 Feb 2008 16:46:07 -0700

Walter Alvarez, world-renowned geologist and author of “T. rex and the Crater of Doom,” is no stranger to scientific revolutions. It was Alvarez, along with his father and two other researchers, who in 1980 published their hypothesis that dinosaurs and other species on Earth were obliterated some 65 million years ago after an object from outer space, either a comet or asteroid, crashed into the planet, creating a large crater and a massive dust cloud.

Alvarez, a professor of geology at the University of California, Berkeley, will deliver a lecture Feb. 21 on scientific revolutions that shaped history, as this year’s recipient of the Eugene Shoemaker Memorial Award presented by BEYOND, the Center for Fundamental Concepts in Science at Arizona State University. The 7:30 p.m. lecture will be given in the Great Hall located in Armstrong Hall on ASU’s Tempe campus.

“Alvarez is world famous for his widely-accepted impact theory and his extensive research in plate tectonics and geomagnetic reversals,” says Paul Davies, an ASU professor and director of BEYOND in ASU’s College of Liberal Arts and Sciences. “It’s fitting to honor him as the second recipient of the Shoemaker Memorial Award.”

Shoemaker was known for his pioneering research with his wife, Carolyn, in the field of asteroid and comet impacts. Last year’s recipient was Apollo 17 astronaut Harrison Schmitt.

In 1988, the Shoemakers named a minor planet “Alvarez” (1985 HC), in honor of Alvarez and his father, Luis, a Nobel laureate.

Among many other contributions to the field of astronomy, Shoemaker, his wife, and their friend David Levy, discovered a comet that collided with Jupiter in 1994. That comet was named the Shoemaker-Levy 9.

The Eugene Shoemaker Memorial Award is presented each year to a leading scientist in honor of his or her life and work.

This year’s recipient, Alvarez, joined the faculty at the University of California, Berkeley, in 1977, when he began a study of the mass extinction at the end of the Cretaceous Period (the final years of the age of dinosaurs) as recorded in the Italian limestones. Evidence from iridium measurements suggested that the extinction was due to impact on the Earth of a giant asteroid or comet, and, many years later that hypothesis was confirmed by the discovery of the largest impact crater on the planet, in the subsurface of the Yucatán Peninsula, dating from precisely the time of the Cretaceous-Tertiary extinction.

From 1994 to 1997 Alvarez was chair of the Department of Geology and Geophysics at the University of California, Berkeley, and since then has returned to teaching and to research centered on Mediterranean tectonics, impact events and Earth’s history as recorded in the sedimentary rocks of the Colorado Plateau and in the deep-water limestones of Italy.

His current interest is “Big History,” the emerging interdisciplinary field that aims to tie everything in Earth’s past – its cosmic ancestry, its geological and paleontological evolution and the pageant of human societies – into a coherent understanding of the grand sweep and character of history. His Feb. 21 lecture at ASU is titled “Scientific revolutions that shaped history: From the Portuguese explorers to Gene Shoemaker and the planets.”

Alvarez is a recipient of the Penrose Medal, the highest honor of the Geological Society of America, and is a member of the National Academy of Sciences. He earned a doctorate in geology from Princeton University and a bachelor’s degree in geology from Carleton College in Minnesota.

The Eugene Shoemaker Memorial Lecture is free and open to the public. Seating is limited and reservations are required. Information at beyond.asu.edu or 480-965-3240.

Carol Hughes, carol.hughes@asu.edu
480-965-6375
College of Liberal Arts and Sciences

China, U.S. students explore Mars at ASU

lccampb — Wed, 23 Jan 2008 12:03:00 -0700

In the first-ever program of its kind, joint teams of U.S. and Chinese high school students will start exploring Mars firsthand at ASU.

Beginning Jan. 27 and running for nine days, 16 students drawn from all across China will meet with eight equally skilled students from Nogales (Ariz.) High School. Together, the space-minded students will take part in the China Youth Space Academy at ASU’s Mars Space Flight Facility.

Mars is a natural focus because ASU’s School of Earth and Space Exploration is an international leader in space science, with instruments operating in orbit and on the surface of Mars.

Each student team, consisting of U.S. and Chinese students, will decide on a Mars geological problem to solve. The teams then will command the Mars Odyssey spacecraft, which is in orbit around the Red Planet, to take images and data to solve the problems.

In the final step, the student teams will analyze their data and report on their findings, just as working scientists do.

“The Space Academy program was created to excite high school students from the United States and China about careers in space science and engineering,” says Jennie Si, a professor of electrical engineering in ASU’s Ira A. Fulton School of Engineering.

Si also is director of ASU’s China initiatives and special projects in the Office of the Vice President for Research and Economic Affairs.

The Chinese students were chosen through an academic challenge joint partnership between ASU, the Chinese government-run Web site china.com.cn and Flying Spirit International Ad (Beijing) Co.

More than 12,000 students registered to take an online test that evaluated the students’ knowledge of the solar system and space exploration. Forty semifinalists then competed in November for two days to produce the 16 winners.

Rick Shangraw, ASU’s vice president for research and economic affairs, led a delegation of five ASU faculty and staff members to serve as judges for the competitions, which took place in Beijing.

The online test and the final competition, which included designing a human outpost on Mars, were developed by ASU staff members in the School of Earth and Space Exploration. The competition questions and challenges reflected the combined science and engineering focus of the school.

“The Chinese students who entered the Space Academy competition were all very impressive,” says Philip Christensen, Regents’ Professor of Geological Sciences and director of ASU’s Mars Space Flight Facility.

Christensen also is the designer of the instrument on Mars Odyssey that the student teams will use to study Mars. During the final round of competition in Beijing, Nov. 17-18, Christensen was one of the judges.

For their team projects at ASU, all the students will be working under Christensen’s guidance.

The Nogales students also have a long space exploration pedigree.

“Students from this high school have taught NASA administrators and other government officials how to take Mars images,” says Brian Grigsby, director of ASU’s Mars Education Program. “The Nogales students have also organized space-related events in their city, and they have helped teach other students throughout the area about space exploration and science.”

The China Youth Space Academy is one of the many ways ASU’s School of Earth and Space Exploration is educating the next generation of space explorers. The school aims to fuse the study of science with engineering and send its graduates on career paths to expand knowledge of Earth, the solar system and the universe.

“The China Youth Space Academy will carve a new path in cross-cultural learning,” Si says. “ASU is committed to finding and developing brilliant minds from around the country and the world.”

Robert Burnham, robert.burnham@asu.edu
(480) 458-8207
Mars Space Flight Facility

ASU research solves solar system quandary

lccampb — Tue, 22 Jan 2008 17:36:57 -0700

Quick: What’s the order of the planets in the solar system? Need a little help? Maybe the following mnemonic rings a bell: “My Very Educated Mother Just Served Up Nine Pizzas.” It’s useful for remembering the order of the planets today, but it wouldn’t have been as useful in the past, and not just because the International Astronomical Union demoted Pluto to “dwarf planet” last year.

The reason this mnemonic wouldn’t have worked is because the planets weren’t always in the order they are today. Four billion years ago, early in the solar system’s evolution, Uranus and Neptune switched places.

This is the result of recent work by Steve Desch, an assistant professor in ASU’s School of Earth and Space Exploration. The work appears in a recent issue of Astrophysical Journal. Desch based his conclusion on his calculations of the surface density of the solar nebula, which is the disk of gas and dust out of which all of the planets formed. The surface density – or mass per area – of the solar nebula protoplanetary disk is a fundamental quantity needed to calculate everything from how fast planets grow to the types of chemicals they are likely to contain.

It’s very hard to observe the surface density in protoplanetary disks forming solar systems today, both because they’re too far away and because most observations detect only dust and miss everything larger than a baseball. So, for the last 30 years, most researchers have relied on an estimate of the surface density: the Minimum Mass Solar Nebula.

The idea is simple: take the rocky component of each planet, add hydrogen and helium until it matches the Sun in composition, and spread the mass over the area of each planet’s orbit. The minimum mass solar nebula predicts disk masses not too different from what we can observe in forming solar systems. But it also predicts low surface densities, with the mass too spread out to form planets quickly.

“I was thinking about planet formation and noticing that all the current models failed to predict how Jupiter could grow to its current size in the lifetime of the solar nebula,” Desch says. “Given Jupiter’s composition and size, models predicted it would take many millions of years for it to form, and billions of years for Uranus and Neptune – but our solar system isn’t that old. That’s when I ran across the Nice model.”

The Nice model (named for the city in France where it was developed) is based on sophisticated numerical calculations of the planets’ orbits over millions of years. It explains several aspects about the orbits of Jupiter, Saturn, Uranus and Neptune, as well as the Kuiper Belt of comets beyond, by assuming the giant planets formed a lot closer together than they’re found today.

Neptune, for example, formed less than half the distance from the Sun that it orbits today. And in 50 percent of their simulations, Uranus and Neptune switched places, although there was no way to determine whether they did or not.

Desch realized the Nice model implied the mass of the solar system was packed together more tightly than the minimum mass solar nebula assumed. By spreading the masses of the planets over their original orbits, as predicted by the Nice model, he found a very smooth variation of surface density with distance from the Sun, albeit one that fell off very sharply far from the Sun. The fit varied by only a few percent from the planets’ masses, but only if Uranus and Neptune did indeed switch places.

“Neptune had to form closer to the sun than Uranus, or you don’t get the smooth profile,” he says.

The new findings have other profound implications, too.

“The surface density of the solar nebula isn’t what we originally thought – it is actually much higher – and this has implications for where we formed and for how fast planets grow,” Desch says. “A higher surface density of the solar nebula means that Uranus and Neptune formed closer and faster, in only 10 million years instead of billions.”

That’s important because Uranus and Neptune contain a few Earth masses of hydrogen and helium gas, and observations of other protoplanetary disks show these gases don’t hang around for more than 10 million years.

In addition to demonstrating for the first time that all of the giant planets can grow within the lifetime of the solar nebula, Desch also uncovered the reason behind the sharp variation in density with distance from the Sun.

“The distribution of mass falls off very steeply because the outer edge is constantly being boiled away through the process of photoevaporation, by the ultraviolet radiation of nearby massive stars,” he says.

Before this, researchers had not considered the effects of photoevaporation on the mass distribution of the solar system. Desch’s work shows that photoevaporation does move mass from the outer edge – but at a fixed rate, so it keeps it from spreading out too much, thus aiding planet growth.

So it seems that 4 billion years ago, “My Very Educated Mother Just Served Nine Up Pizzas” would have been the mnemonic to learn.

“This reminds us that the solar system is a dynamic place,” Desch says. “For the first 650 million years of the solar system, Neptune was closer to the sun than Uranus – that’s 15 percent of the history of the solar system. It looked completely different than we see it today.”

Nikki Staab, nstaab@asu.edu
(480) 965-8122
School of Earth and Space Exploration

Spanias to lead NSF-funded project

Thu, 20 Dec 2007 14:56:51 -0700

Andreas Spanias, a professor in the Department of Electrical Engineering and director of the SenSIP (Sensor, Signal & Information Processing) consortium, is leading a collaborative National Science Foundation (NSF)-funded project to develop a software program designed to aid earth science research.

Spanias and his team – including Linda Hinnov, the project’s director and an associate research professor in the Department of Earth and Planetary Sciences at Johns Hopkins University, and James Ogg, a professor in the Department of Earth and Atmospheric Science at Purdue University – will participate in the three-year, $575,000 project, titled “Collaborative Research: An Astronomical-Calibrated Time Scale for the Mesozoic Era.”

The team will use a Java-DSP (digital signal processing) software package, a visual Web-based programming environment developed by ASU electrical engineering faculty and graduate students working with SenSIP.

Java-DSP, which has been used for wireless sensing research and DSP education technology projects funded by NSF, is available on the Web for public use.

For their part in the new collaborative project, Spanias and his team will create a new Java-DSP program – J-DSP/Earth Systems Edition (J-DSP/ESE) – that will enable scientists to use modern signal processing techniques to address problems in earth systems research.

Sci-fi meets sci-fact at lecture

chughes3 — Tue, 06 Nov 2007 07:41:00 -0700

It’s sci-fi meets sci-fact when internationally known physicist Lawrence Krauss and actor Armin Shimerman guide audience members on a warp speed journey through the fantasies of science fiction via the "Star Trek" universe and the exciting possibilities of the real universe, including the fascinating world of modern physics. The multimedia presentation will begin at 7:30 p.m. Nov. 8 at the Tempe Center for the Arts, 700 W. Rio Salado Parkway, Tempe.

Hosted by Beyond, the Center for Fundamental Concepts in Science at Arizona State University, the presentation is free and open to the public, but reservations are required. Seats are still available and may be reserved online at beyond.asu.edu/register.html or by calling (480) 965-3240.

Krauss, a professor of physics and astronomy at Case Western Reserve University in Cleveland, Ohio, and the author of "The Physics of Star Trek," will talk about topics ranging from time travel to warp speed, from the Big Bang to the search for extraterrestrial intelligence. Shimerman, who played the "Star Trek" Ferengi character Quark and appeared in a dozen different science fiction TV shows, brings a cache of science fiction with him for this event. Shimerman also is an author, writing a series of science fiction novels under the Merchant Prince title.

The talk – Beyond the Star Trek Universe – is the first in what is planned to be an annual "science behind science fiction" event, says Paul Davies, director of ASU’s research center Beyond. More information about the center is online at beyond.asu.edu.

White House honors ASU faculty

chughes3 — Thu, 01 Nov 2007 10:06:05 -0600

Two young scientists at Arizona State University – a geophysicist and an educational psychologist – are among 58 recipients of the 2006 prestigious Presidential Early Career Award for Scientists and Engineers (PECASE). Having two faculty members receive this national award is a first for ASU.

Matthew J. Fouch, an associate professor in the School of Earth and Space Exploration, and Jenefer Husman, an assistant professor in the Mary Lou Fulton College of Education, were recognized in a ceremony at the White House Nov. 1.

The Presidential Early Career Award for Scientists and Engineers, established in 1996, honors the most promising researchers in the nation within their fields. Nine federal departments and agencies annually nominate scientists and engineers at the start of their independent research careers.

Selection for the award is based on innovative research at the frontiers of science and technology that is relevant to the mission of the sponsoring organization or agency, and community service.

Fouch and Husman were nominated by the National Science Foundation, which provides grant support for five years through its Faculty Early Career Development (CAREER) program.

“These awards underscore the exceptional talent at ASU,” says Elizabeth D. Capaldi, ASU’s provost. “To earn two of only 58 national awards is a remarkable achievement. I congratulate Dr. Fouch and Dr. Husman. We are all honored by their success.”

Matthew J. Fouch

Gigabytes of data are flowing from the National Science Foundation’s (NSF) project known as EarthScope, and ASU associate professor Matthew J. Fouch and his students are “right in the thick of it.”

Fouch is being honored with a PECASE award for developing new approaches that integrate geophysical data types – seismic and geodetic – to help researchers and students better understand deformation, or the dynamic nature of Earth’s interior, beneath continental North America.

He is one of 20 NSF-nominated recipients of this year’s PECASE honor. Fouch received a NSF CAREER grant last year that supports his work in both developing new approaches to integrating EarthScope as well as bringing data from seismic stations around the world into the classroom.

“There’s no way to get geologic samples from a wide range of places deep inside Earth,” Fouch says. Yet, by developing semi-automated data analysis tools, “Earth science students can perform seismic research in their classroom, using real-time data from a variety of sources, including EarthScope’s seismic monitoring component: USArray.”

And, with EarthScope’s facility now constructed and fully operational, data is being collected and analyzed by Fouch and his graduate students.

“It’s a revolutionary new amount of data for understanding the geologic history of the western United States,” he says. The data can be used to answer questions about historic changes occurring within and beneath Earth’s tectonic plates, such as the Juan de Fuca Plate in the Pacific Northwest.

“This is a region where there have been extreme changes over the last 35 million years and more that are still not well understood. The new data generated by EarthScope and our own seismic arrays in the region are providing a beautiful window into how those processes occur,” Fouch says. “It will generate a profoundly new set of images that shows where the plate is, where it is not and where it appears to have fallen apart.”

That “window” is data-created computer imaging of deep beneath the Earth’s crust.

“We’re using the data to relate the geology at the surface to the structure and deformation (stress and strain) in the depths of Earth,” he says.

This new interdisciplinary approach to collecting and analyzing data, making it accessible to students, and, to the public through lectures, helped earned Fouch these national honors.

“It is an honor to receive this presidential award, which goes beyond the NSF CAREER award,” he says. Such awards, early in his career, have given him the academic and research freedom to explore new directions, “to take risks,” he says.

“With five years of funding from grants like the CAREER award, rather than a typical two-to-three year grant, it’s like receiving two bonus years to do research and think about your research at a much deeper level,” he says. “The extra time allows for more introspection and development of new approaches to your science.”

The award also recognizes Fouch for integrating teaching with research. With a passion for Earth science and a commitment to teaching, his goal is to develop a series of tools that can be used in the classroom, drawing on data from far away points.

Fouch, who has his bachelor’s degree in geology from Pomona College, his master’s and doctoral degrees in geophysics from Brown University, and performed postdoctoral work at the Carnegie Institution of Washington, joined ASU in 2001 as an assistant professor in the Department of Geological Sciences in the College of Liberal Arts and Sciences. He recently was promoted to an associate professor in the college’s new School of Earth and Space Exploration.

“ASU is a very unique place that enables young faculty to achieve CAREER and PECASE awards. The administration here has always been enthusiastically supportive of new and innovative efforts,” he says.

The revolutionary new ways science and engineering are fused in the School of Earth and Space Exploration is one example of how Arizona State University is building a new American university.

“Compared to many places around the country and the world, we’re empowered to be incredibly academically free at ASU. To my mind, it’s like the wild west,” Fouch says. “Anything can go here, in the best possible way.”

Jenefer Husman

Jenefer Husman, an assistant professor of psychology in education, has focused her work as a motivation researcher on understanding the developmental processes of students who pursue and persist in careers in science and engineering, and adding an important link between successful intervention programs and student achievement in these fields.

“Engineering programs across the country have very high attrition rates. This fact led me to suspect that students in engineering may suffer from motivational conflicts,” Husman says. “Engineering is a difficult major that requires students to possess a strong prior knowledge base combined with the ability to persist in the face of difficulties and disappointments.” Additionally, educators must understand how students conceptualize their futures, she says.

Her research study titled “Connecting with the future: Supporting identity and career development in Post-Secondary Science and Engineering,” endeavors to address these goals. The project is being supported by the CAREER program sponsored by the National Science Foundation.

“There is a strong identity associated with becoming an engineer, although not every student can internalize or wants to internalize that identity,” Husman says. “I believe that my research can help engineering educators better understand the identity formation process their students are going through, and how to support their students’ motivation to learn.”

Through the project, Husman and a team of ASU researchers will specifically focus on the concepts and processes that form a person’s future time perspective (FTP). The more accurate, complete and viable a person’s FTP, the more likely, Husman says, they are to succeed, both in the present and in the future.

“By better understanding how students think about their futures in science and engineering, we can better support and guide them, increasing the number of students who choose and succeed in science and engineering careers,” she says.

In an examination of engineering education literature, Husman realized there was very little focused on motivational issues in engineering education. The early catalyst for her research, instead, was born from her own experiences as a young student and scholar.

“When I was in elementary school, I had great difficulty learning. Everything was hard; mathematics, reading and writing,” she says. “Like so many learning-disabled students, I had strengths in some areas and great weaknesses in others.”

Husman says she was fortunate that her instructors noticed this early and took action. “My teachers and parents were all keenly aware of my learning disability and worked with me, after school, at night studying at the kitchen table and on weekends. Helping me learn to work with my learning disability was a family affair.”

When her studies overwhelmed her, Husman’s father reassured her, telling her college would be easier than elementary school.

“Even then, he was setting expectations for me, but supporting my belief in my own ability to succeed academically,” she says. “I knew that, even if things were hard then, in the future I would be successful.”

Husman says it was those early struggles with learning that taught her “what a difficult and fascinating process learning is.” It also taught her how important motivation – the willingness to put forth large amounts of effort – is to student achievement.

“Most importantly, I understood firsthand how important a strong, positive, view of the future is to supporting motivation and learning. My goal is to better understand how people think about their futures and how instructors and parents can help their child develop a clear, positive image of themselves in the future.”

Ultimately, students must have good motivational orientations, in order to choose and succeed in rigorous courses and careers in science and engineering, Husman says. And yet there has been little consideration of the importance or possible impact of existing interventions on students’ motivation for learning to become an engineer.

Husman says ASU is in the unique position to propagate knowledge in this area, having several ongoing programs to support student recruitment and retention in engineering, including the Virtual Counseling Center, which provides programs and instruments for helping students and graduates develop life and career plans, and the campus-based Women in Science and Engineering program.

“These programs support many aspects of students’ learning,” she says.

Joan Sherwood, Joan.Sherwood@asu.edu
480-965-2114
Mary Lou Fulton College of Education

ASU invites community to explore Earth, space

chughes3 — Wed, 31 Oct 2007 12:13:58 -0600

Kids of all ages, and their parents and teachers too, are invited to learn more about Earth and space through hands-on activities, experimental demonstrations and public lectures by ASU scientists from 9 a.m. to 3 p.m. Nov. 3, in the Bateman Physical Science Building, F-Wing, at ASU’s Tempe campus.

The annual Earth and Space Exploration Day, hosted by ASU’s School of Earth and Space Exploration, provides a variety of educational activities “for kids ages 5 to 95,” says professor Tom Sharp, a mineralogist and associate director of the NASA Arizona Space Grant Consortium.

“The purpose of this event is to provide an up-close opportunity for the public to see some of the great science we do at ASU, while we engage students of all ages in fun, hands-on scientific learning activities,” says Sharp. “There is plenty of depth for adults too.”

For example, ASU planetary scientist David Williams will present a lecture on solar system exploration at 10 a.m., and give an overview of results from NASA’s and the European Space Agency’s 2007 planetary missions. Other lectures on black holes, volcanology, the Mars rovers and whether there will be an energy crisis are scheduled on the hour throughout the event.

In conjunction with the day of exploration, ASU’s Space Photography Laboratory is hosting an open house and will show the latest NASA planetary images.

There also will be special shows in the planetarium, including one on “Stars over Arizona.” Other educational activities include learning about minerals while panning for gold, examining rocks and meteorite sections under a microscope, viewing the sun with a solar telescope, and learning about volcanoes and their explosive eruptions.

The public can “take a tour” of Mars with the aid of a GeoWall 3-D projector. Children, and adults can bring in rocks for “Dr. Rock” to identify or water samples for “Dr. Water” to analyze. Minerals, gems, fossils from around the world, the only active seismograph in central Arizona, a six-story Foucault pendulum, and Columbian mammoth bones from Chandler, Ariz., will be on display in the Dietz Museum of Geology.

Also scheduled is a geology field trip to “A” Mountain (Hayden Butte) to learn about sedimentary rocks, volcanic rocks and geological structures exposed in Tempe.

There will be handouts and outreach information for teachers from the School of Earth and Space Exploration and other academic and research units in the College of Liberal Arts and Sciences, including the Institute for Human Origins and the School of Geographical Sciences.

“We hope the event will encourage children to learn that science is fun as they learn about how the Earth works and how we study it,” Sharp says.

The Bateman Physical Science Building is just south of University Drive, between McAlister and College avenues in Tempe. Public parking is free in any ASU lot south of University Drive on Nov. 3. Parking options include the Tyler Street Parking Structure (#2), on the corner of Tyler and McAlister, and in the Rural Road Parking Structure (#4) on Lemon Street and Rural Road. For more information, contact the School of Earth and Space Exploration at (480) 965-5081 or www.sese.asu.edu.

Carla Mitchell, carla.mitchell@asu.edu
(480) 965-1441

Carol Hughes, carol.hughes@asu.edu

(480) 965-6375

College of Liberal Arts and Sciences

ASU astronomers help locate obscure galaxies

ngerbis — Wed, 10 Oct 2007 17:17:57 -0600

If there is one thing parents know about looking for their children’s lost toys, it is to not rule out a possible spot just because the youngsters say they already looked there.

The same could be said for astronomers – they are just looking for much bigger Legos.
Recently, two ASU researchers helped to locate what they call the “Lego building blocks of galaxies.” They did so by looking in a place that other astronomers already had looked, but with fresh eyes.

Using NASA’s Hubble and Spitzer Space Telescopes, an international team of astronomers found nine of the smallest, faintest, most compact galaxies ever observed in the early universe – the building blocks of today’s larger, older galaxies.

The team, which includes associate professors Sangeeta Malhotra and James Rhoads of ASU’s School of Earth and Space Exploration, announced the discovery of these protogalaxies Sept. 6. Nor Pirzkal of the Space Telescope Science Institute in Baltimore led the study, which also included Chun Xu of the Shanghai Institute of Technical Physics in China.

Composed of millions of brilliant blue stars, each infantile galaxy is one-hundredth to one-thousandth as large as our Milky Way galaxy and formed about 12.5 billion years ago – just 1 billion years after the “Big Bang.”

Such galaxies are consistent with the conventional model of galactic formation, which holds that larger galaxies are formed when younger, smaller, less-massive galaxies merge. The sighting thus offers some much-needed support for the “hierarchical model,” which has become ever more contentious in recent years.

The controversy, like the discovery, is a question of observation.

One of the oddities of astronomy is that looking at distant objects also means looking back in time. Light, the fastest thing in the universe, still takes time to get from object to observer, meaning that scientists are always looking at snapshots from moments long ago.

If the conventional model is correct, then astronomers peering “deep” into the early days of the universe should detect “building block” galaxies akin to the ones announced Sept. 6. As yet, however, researchers have predominantly found older, more massive galaxies – causing some to question the hierarchical theory.

One explanation for observations skewing toward finding older galaxies is the Spitzer telescope itself, which specializes in seeing into the infrared spectrum.

“Spitzer is very good at detecting old stars,” Malhotra says. “When you see an old galaxy with Spitzer, it is exciting to publish articles saying, ‘Hey, old stars in a young universe.’ But when people don’t see galaxies with Spitzer, it’s a nondetection, and not much is made of it.”

Malhotra and Rhoads, along with their colleagues, wondered if these nondetections could be masking the very galaxies they sought. If these expanses of space did not contain old galaxies, might they not hold young ones?

To find out, the group turned to the Hubble Space Telescope.

“With the Hubble Space Telescope, we were able to find emissions in blue light, which meant that there were a lot of young stars in those galaxies,” Malhotra says. “The question was, underneath all of that, was there a substrate of old stars that came from a previous generation? For that, we had to look at the red light data, which came from Spitzer.”

By analyzing the spectral energy distribution data available from the two telescopes’ instrument arrays, the team determined that the nine blue galaxies indeed lack old red stars – and that they are also not very massive.

The spectral data also showed that the galaxies were very blue, implying that they are largely dust-free. Just as atmospheric dust makes sunsets red, dust between stars and observers on Earth makes starlight appear redder.

All of this was good news because, while Legos might be found in dusty corners of the house, building blocks of the galactic sort are more likely to be located in dust-free zones.

“Dust is a sign that a galaxy has been around for a while, because it is made of heavier elements that are themselves produced in stars,” Rhoads says. “So if there is a lot of dust, it means that the galaxy has been around long enough for dust to be formed in stars and dispersed back into gas between the stars at least once.”

Rhoads – who, along with Xu, first identified these galaxies – added that three of the galaxies appear to be stretched into tadpole-like shapes instead of the usual rounded blobs, which could suggest that they are in the process of merging with neighboring galaxies to form larger, cohesive structures.

In the effort to see the early universe, sometimes looking twice pays off.

“If you want to have a fair idea of what’s going on in the old universe, then you have to pay attention not only to what you see, but also to what you don’t see,” Malhotra says. “So, in this case, we don’t see old stars – and that’s big news.”

ASU scientists keep an eye on Martian dust storm

gcampbel — Wed, 11 Jul 2007 14:34:15 -0600

Scientists at ASU’s Mars Space Flight Facility are using the Thermal Emission Imaging System (THEMIS) on NASA’s Mars Odyssey orbiter to monitor a large dust storm on the Red Planet.

The instrument, a multiwavelength camera sensitive to five visible wavelengths and 10 infrared ones, is providing Mars scientists and spacecraft controllers with global maps that track how much atmospheric dust is obscuring the planet.

The dust storm, which erupted during the last week of June, is affecting operations for all five spacecraft operating at Mars. The fleet includes two NASA rovers on the ground (Spirit and Opportunity), plus three orbiters, two of which belong to NASA (Mars Odyssey and Mars Reconnaissance Orbiter) and one to the European Space Agency (Mars Express).

Beginning in the equatorial region west of Meridiani Planum, the storm moved into the heavily cratered southern highlands. It took roughly a week to grow large enough to spread around the planet south of the equator. Dust has now drifted into the northern hemisphere as well.

“This is the favorable time of the Martian year for dust storms,” says Joshua Bandfield, research associate at the Mars Space Flight Facility.

The facility is part of the School of Earth and Space Exploration in ASU’s College of Liberal Arts and Sciences.

“It’s summer in the southern hemisphere,” he says. “That’s when Mars lies closest to the sun and solar heating is greatest. We can watch weather fronts spreading and kicking up dust in a big way.”

Bandfield says that as winds sweep dust into the atmosphere, the atmosphere becomes warmer. This adds to the storm’s power, helping it to pick up more dust.

But the process has a built-in limitation, he says.

“When the dust becomes thick enough, it reflects more sunlight from the atmosphere, allowing the air near the surface to cool,” Bandfield says.

As seen from orbit, the dust storm has the effect of veiling surface features – or even concealing them completely, which hasn’t happened yet in this event.

“This storm isn’t as big or severe as the one in 2001,” Bandfield says. “THEMIS and other orbiters can still see the surface, despite the continuing dust activity.”

From the ground, the dust in the air has cut the amount of sunlight reaching the rovers’ solar panels, thus reducing their electrical power.

“If you were standing there, you’d see the sky looking tawny with haze,” he says. “The sun would appear as a sharp-edged disk, but the light level would be noticeably lower than what you would see under a totally clear sky.”

Luckily, say scientists, summer is a time when the rovers can best survive under reduced power. If the storm had struck during local winter, the rovers might not get enough power during the day to stay alive through the cold Martian night.

How long will this storm last? No one knows for sure, but Bandfield notes its effects won’t disappear as quickly as the storm erupted.

“Mars will remain dusty for at least a couple months more,” he says.

Mars dust map images are available online at themis.asu.edu/dustmaps. At infrared wavelengths, the smallest details THEMIS can see on the surface are 330 feet (100 meters) wide. Philip Christensen, Regents’ Professor of geological sciences in ASU’s School of Earth and Space Exploration, is director of the Mars Space Flight Facility, as well as the designer and principal investigator for the THEMIS instrument.