Department News

The OSIRIS-REx mission was highlighted in the Spring 2013 edition of Arizona, the UA alumni magazine, with a suite of six articles featuring Professor Dante Lauretta and some of the UA students (graduate and undergraduate) working on the mission project.

OSIRIS-REx Mission: Are We Stardust?

OSIRIS-REx Students

A Scientist, Runner, and Musician Pulls an Intricate Camera System Together - on Deadline

A Sophomore Writes Code to Track a NASA Robot

An Engineer - and his Dog - Settle In To Make History

Creative Writing Meets Planetary Science

The Camera Man

In celebration of Women's History Month 2013 (Women Inspiring Innovation Through Imagination: Celebrating Women in Science, Technology, Engineering and Mathematics), the OSIRIS-REx team developed some online resources for promoting celebrating women in STEM careers. Several current and former LPL faculty, staff, and students are featured, including Nadine Barlow, Veronica Bray, Kat Crombie, Renu Malhotra, Elisabetta Pierazzo, and Elizabeth Roemer. 

Check out the videos, booklists, PowerPoint shows, and biographies online here.

Sarah Mattson, Senior Staff Technician with the HiRISE project, received an Emily Krauz scholarship from the University of Arizona Staff Advisory Council for the fall 2012 semester. The scholarship award is intended to support UA classified staff in career advancement or continuing education and professional development. Sarah applied the award to enrollment in an optics course (Linear Systems and Fourier Analysis).

Congratulations, Sarah!

The first LPL Women's lunch had an impressive turnout of 36 women, representing alumnae, faculty, staff, and grad students, and many people who are combinations thereof.  We came from the Kuiper, Sonett, and Drake buildings as well as JHUAPL, BYU, and Caltech (thanks to the Titan Working Group Meeting for bringing the out-of-towners).  As a result of the lunch, our email discussion list has grown from less than twenty members to over fifty. Anyone interested in joining the email list can subscribe here.

Additionally:

• The personalized tour of HiRISE science operations for Drake Building people after the LPL Staff Colloquium was a joint effort organized by women who made contact at the event. We intend to continue the tradition across the LPL buildings whenever possible.

• Because there is demonstrated interest in continuing group events, Ingrid Daubar and I submitted a mini-grant proposal to the university's Committee on the Status of Women for funding to support future meetings, networking opportunities, guest speakers, and mentoring, community building and outreach events. The mini-grant proposal was successful, and the "LPL Women" project was awarded funds in support of fostering a sense of community within the women of LPL; fostering a sense of community and inclusion on campus by reaching out to other women in science groups through joint discussions or social events; providing time and space to discuss issues such as those raised by the Strategic Planning Committee; increasing awareness of resources and career options; participating as "LPL Women" at LPL general public and children's outeach events.

• A number of LPL Women are now connected to Steward Observatory's Women in Science Forum and vice-versa, a trend Vanessa Bailey (graduate student in Astronomy) and I are actively promoting.

We welcome new members and ideas for further activities!

The UA Campus played host again this spring to the annual Tucson Festival of Books. This year's event, the fifth annual festival, was held March 9-10, 2013; the event was a huge success despite some wild spring weather at the start.

LPL faculty, staff, and graduate students participated in the festival as part of the UA ScienceCity, located on the UA mall directly in front of the Kuiper Space Sciences building. Highlights of the LPL events included OSIRIS-REx staff and ambassadors describing the mission and talking about meteorites and impact cratering. Also featured was Assistant Professor Tamara Rogers, who presented an informal talk on "Mysteries of the Sun: What We Know and What We're Learning." This opportunity for outreach was greatly facilitated with volunteer staffing from the College of Science community volunteers.

The Tucson Festival of Books is free and open to the public. It has become one of the most anticipated and well attended book fairs in the U.S., attracting approximately 100,00 attendees, 450 authors, and 300 exhibitors.

Whether by telescope or spacecraft, when we look at the surfaces of other planets we do so through remote sensing instruments.  There is a wide variety of such instruments from Synthetic Aperture Radars to visible wavelength cameras and an even wider range of geologic features to examine from sand dunes to lava flows.  On Earth, remote sensing is further complicated by vegetation and features constructed by humans.  However, there is one great advantage to remote sensing data analysis on the Earth – you can actually visit the site to test your conclusions…

On this trip we packed our bags for the Mojave Desert, but not before doing some analysis of remotely sensed data from a variety of instruments on both aircraft and spacecraft.  In this way we aim to test our ability (or the data’s ability) to determine something of the surface properties in advance.  The Mojave is a great area for such an experiment both because it has a wide variety of geology and because it is well covered by many different datasets.

After a lengthy drive, our first stop was the Kelso dunes.  Armed with a shovel (the shovel actually saw a lot of use on this trip), we set out to explain the appearance of the dunes in Synthetic Aperture Radar (SAR) datasets. These data show the dunes are dark in the shorter wavelength bands (such as the 5cm C-band) and brighter in the longer wavelength bands (such as the 25cm L-band and 80cm P-band).  Some digging revealed a possible cause – the upper sand is dry quartz grains (with a low dielectric constant that doesn’t scatter radar waves well); however, about 20-30 centimeters (8-12 inches) below the surface a wet layer was found. The longer wavelength radar waves may be sensing this higher dielectric constant layer and scattering more. It was late in the day, but after racking their brains about what to do next some people managed a moonlit hike to the top of the dunes.

Kelbaker Road runs through the Mojave and is full of interesting sites. Just a few miles from Kelso, we stopped at a rock outcrop that we had identified as ‘interesting’ in some hyperspectral imaging data.  Two spectrally distinct rocks were visible here that turned out to be a limestone and a shale. They in turn were quite distinct from the surrounding alluvium, which turned out to be dominated by coarse quartz grains. We pressed onward to Old Government Road, which led us down to Soda Lake (a playa).  SAR data show the playa surface to behave very differently in C, L and P bands and to have large variations from place to place.  Some more digging revealed that many of these differences were probably due to the depth where the playa sediment transitions from dry to wet.  Additionally, roughness differences between parts of the playa dominated by silt and parts dominated by evaporate deposits contributed to the differing radar brightnesses seen in the data. The Cima volcanic field was next door and we stopped here to look at roughness differences between volcanic flows of different ages and how they manifested themselves in the radar data.  Many of the Cima cinder cones also show spectral differences between their summits and lower flanks in our hyperspectral datasets.  Close inspection from hiking to the top and back (which proved to be more involved than expected) of one cone suggested weathering differences of the cinders led to the spectral differences. Finally at Cima we checked out a lava tube cave.  Recent high-resolution planetary cameras have resulted in the discovery of several such caves on Mars and the Moon.

The next day we drove a loop around the Mojave stopping first at some agricultural fields.  Some enigmatic radar-bright radial bands in these circular fields are probably due to concentric ridges at the L-band wavelength scale that result from the concentric planting of alfalfa grass.  The strongly depolarized radar return here is probably due to the vegetation itself.  Such pathological topography (not to mention the vegetation) is unexpected on other planetary surfaces.  Our second stop of the day was the Pisgah lava flow and cone (or rather what’s left of it as it’s being mined away).  We investigated obvious brightness and depolarization contacts in the radar data of the lava field that correlated with dramatic changes in surface roughness.  We also had the chance to explore Glove cave, another lava tube, and hear about the astrobiological research that happened there and its relevance for other lava tubes around the solar system.

Our final stop for this day was the Amboy lava field and cinder cone.  In visible-band orbital imagery the Amboy cone has a dark streak emanating from it to the southeast. Examination of C-band radar data suggests the streak also scatters more radar energy.  Rick Greenberg joined the trip in his plane and flew to Amboy to help us characterize the streak from the air.  On the ground the margins of the streak are very diffuse, but with the help of Rick and his passengers we were able to locate it.  Unfortunately the weather and delays on the road meant we only had the time to map out its northern edge.  The formation of the streak seems to be related to the rate of delivery of silt-size material. Within the streak, this rate seems slow enough that the dark rocks can rise to the surface forming a dark desert pavement with the brighter silt underneath. Outside the streak, continuing silt delivery seems fast enough to keep these dark rocks buried.  The radar brightness difference may also be related to this. Basalt contains appreciable iron, which the silt does not.  A desert pavement of basaltic pebbles is both rougher and has a higher dielectric constant than areas dominated by silt.

Rick and crew landed safely and camped with us in Amboy that night. The next morning we visited Broadwell lake (another playa), which (in contrast to Soda Lake) is homogeneously dark at all radar wavelengths.  The surface here is smooth packed silt and bone dry as far down as we could dig.  There’s nothing in the surface composition or roughness to scatter radar power in the backward direction towards the receiver.

A trip to the Mojave is always fun from a geological perspective. This time however we also gained a little remote sensing intuition.  Other places in the solar system are less easy to visit, but hopefully we can make more sense of their surfaces now.

Despite our tendency to crisscross the whole southwestern U.S. on these trips, there is an incredibly interesting geologic story sitting on our doorstep here in the Tucson area.  There has been growing interest among the fieldtrip group in understanding more about the processes that have fashioned the local landscape around Tucson and that was finally satisfied this semester.

From a geological point of view, we’re fortunate here in the Southwest to be so close to the edge of North America.  Our geologic story is largely shaped by our proximity to this active plate boundary over the past hundred million years or so.  Prior to that, southern Arizona had a mix of dry periods and marine incursions.  One of these marine periods led to the formation of limestone rocks, which would likely have remained obscure were it not for the fabulous caves that formed within them. We had the chance to visit one of these caves at Kartchner Caverns, discovered less than 40 years ago by Gary Tenen and Randy Tufts (an LPL alum).  Other sedimentary rocks that predate the main volcanic and tectonic stories recorded at Tucson can be seen east of the Tucson Mountains too.  However, most of the geologic story we followed started in the late Cretaceous – just before the disappearance of the dinosaurs.

About seventy million years ago there was an oceanic plate (called the Farallon plate), to our west, that was in the process of disappearing beneath North America.  As younger and younger portions of this oceanic plate were dragged beneath our continent they began to float higher and eventually grate along the underside of North America compressing our continent and building mountains.  A wave of volcanic activity passed eastward through the Tucson area ahead of this and large ash-flow calderas dotted the landscape. We visited the remnants of one of these in the Tucson Mountains.  Here, large quantities of volcanic ash are welded together forming the rocks we see (and can be comfortably examined at Gate’s Pass).  During this period, hydrothermal circulation around the subterranean magma chambers led to the concentration of much of Arizona’s copper and other minerals that we continue to mine today.

Probably the most shocking part of this part of the story is that the Tucson Mountains are no longer sitting above the magma chamber that fed them.  That magma chamber is likely part of the Catalina and Rincon mountains on the other side of town! How then did the surface volcanoes end up so far away from where they started?  As the trailing edge of the Farallon plate disappeared beneath North America its angle of descent steepened and it stopped compressing the continent. The mountain ranges produced earlier began to collapse and the crust to spread outward. This crustal spreading manifested itself on the surface in the Tucson area as nearly horizontal faults. Thus the Tucson mountains were able to slide, nearly horizontally, westward off the top of their (now solidified) magma chamber.  Without the weight of the Tucson Mountains above it, the buried granite could rise up buoyantly above the surface.  The Rincon and Catalina Mountains are these magma chambers. We visited the fault where the surface rocks slid off the buried magma chambers to the south and east of these mountains.  Having the surface volcanoes scrapped off like this has consequences for the granite of the magma chamber too. The heat and pressure generated in the region being sheared metamorphoses the granite into mylonite – a rock with a texture that can tell you details of the direction of the shear.  We saw plenty of examples of mylonite on the Catalina Highway – this metamorphism progressed to different extents in different places and is barely apparent at all behind the steep Catalina forerange.  These uplifted partly-metamorphosed magma chambers, where the original surface rocks have been moved off, are called metamorphic core complexes.  They are known to be widespread now, but were first recognized in this classic Tucson example.

Stretching of the crustal rocks continued in a different form as the Farallon plate peeled away from the underside of North America and volcanic activity returned producing dikes that are visible today in the Tucson Mountains.  Steeper faults now formed and occurred in sets that allowed intervening valley floors to drop downward nearly intact.  The alternating basins and mountain ranges this produced can be seen throughout the southwest. Tucson itself sits in one of these basins and we visited a classic example of one of these basin-and-range faults near Oracle named the Pirate Fault.

With the basin floors dropping, the surrounding mountains shed material that began to fill in these low areas.  This continues to this day and we saw examples of bedrock channels and debris flows that have contributed material to the basin fill.  As the mountains erode backward and shed more debris both alluvial fans and pediment surfaces can form.  Compaction of sediment above buried pediments can also lead to fissures opening up on the surface – a process that we saw has accelerated around Wilcox in recent times as groundwater is mined for agriculture.

Within the infilling basins, lakes alternated with playas as climatic conditions shifted. Eventually the basins became so full of sediment that they began to overflow allowing drainage waters to move from basin to basin.  After the basins were integrated in this way lakes gave way to thoroughgoing rivers. The San Pedro river sediments tell this complete story very well and there are great exposures of them in the Saint David’s Formation near Benson.

Despite all the buildings, agriculture and people around Tucson there’s still a lot of geology to see.  This trip has certainly provided us with an appreciation of the local story and how it fits into the broader forces at work as Earth’s tectonic plates (and perhaps those of some extrasolar planes) jostle past each other over geologic time.

On May 1, NASA announced that the OSIRIS-REx target asteroid 1999 RQ36 was renamed Bennu. The name Bennu was selected from over 8,000 entries submitted to the Name that Asteroid! contest. Bennu was an important avian deity in ancient Egypt and one of the symbols of the god Osiris. Egyptians usually depicted Bennu as a gray heron. The double nature of asteroids delivering life’s molecules and sometimes bringing destruction such as the recent fall in Chelyabinsk, Russia, inspired the mission name, OSIRIS-REx, and now the asteroid’s name. Nine-year old Mike Puzio submitted the winning entry, stating, 
“The winged OSIRIS-REx and its heron-like TAGSAM evoke attributes of Bennu, as does the egg shape of the asteroid itself.”

OSIRIS-REx will launch in 2016, rendezvous with Bennu in 2018, and take a sample in 2019.

More information about how Bennu got its name is available on the OSIRIS-REx site and in the UA News press release.

Early this year, the International Astronomical Union announced the naming of asteroids after two women with strong ties to LPL.

Asteroid 1999 YV 22 (discovered December 31, 1999, MPC 79104) has been officially designated (75562) Wilkening and asteroid 2000 BF34 (discovered December 31, 2000, MPC 82401) has been officially designated (25760) Annasptiz. Both asteroids were discovered by LPL's Catalina Sky Survey.

Laurel Wilkening was on the LPL faculty from 1973 to 1983 and served as PTYS/LPL Head and Director from 1981 to 1983. She is now retired and living in Tucson. More about Laurel Wilkening's fascinating life is available from a 2001 NASA oral history project ("Herstory") interview available online from NASA Johnson Space Center.

Anna Spitz received her Ph.D. working with Professor William Boynton in 1991 and is currently Education and Public Outreach lead for the OSIRIS-REx mission.

Congratulations to Dr. Wilkening and Dr. Spitz!

The LPL Board of Advisors, the external group chartered with helping LPL and its director improve interactions with the world beyond campus and NASA, has been reformulated after a several year absence. The group will have its initial meeting in June to set goals and begin work. The Board members range from LPL alumni to Tucson community leaders who have not been part of the LPL family before. You’ll be hearing more from the Board as time progresses. Board members are:

David Acklam is a retired engineer who has been very active in astronomical outreach in the Tucson area. As well as being the chair of LPL’s Kuiper Circle Community Outreach committee, he is also an OSIRIS-REx Ambassador, a volunteer telescope operator at Flandrau Science Center, a Friend and docent at the Planetary Science Institute, and a volunteer Project ASTRO astronomer partner. Acklam is also a member of the Tucson Amateur Astronomy Association and the Planetary Society. He received his BSEE and MS from the University of Arizona and was a career Air Force officer, before moving to Texas Instruments and then Raytheon Missile Systems.

Dan Cavanagh is a 1974 Communications graduate of the University of Arizona. His varied background includes being President of the American Chamber of Commerce Government Relations Council and being a leading contributor to radio networks and wire services though out North America. He has spent 40 years in Southern Arizona developing/serving on successful efforts impacting public policy, taxation, the arts and education. Cavanagh's most recent position was Southern Arizona Manager of Government Affairs for the world's largest publicly traded copper company, Freeport McMoRan.

Chris Lewicki is the President and Chief Engineer of Planetary Resources, the asteroid mining company. He received his bachelor’s and master’s degrees in Aerospace Engineering from UA, and worked at LPL with Professor Bill Boynton’s group. He was then intimately involved with the lifecycle of NASA’s Mars Exploration Rovers and the Phoenix Mars Lander. Lewicki performed system engineering development and participated in assembly, test and launch operations for both Mars missions. He was Flight Director for the rovers Spirit and Opportunity, and the Surface Mission Manager for Phoenix. The recipient of two NASA Exceptional Achievement Medals, Lewicki has an asteroid named in his honor, 13609 Lewicki.

Laura McGill is Engineering Deputy of Raytheon Missile Systems, the largest private employer in southern Arizona. A principal engineering fellow, McGill was formerly deputy director for Advanced Medium Range Air-to-Air Missiles and Special Programs. She holds a bachelor’s degree in aeronautical and astronautical  engineering from the University of Washington and a master’s degree in aerospace systems through a General Dynamics engineering development program. She is a lifetime fellow of the American Institute for Aeronautics and Astronautics (AIAA) and a member of its board of directors.

Jani Radebaugh, who obtained her PhD in planetary science from LPL in 2005, is an associate professor of geological sciences at Brigham Young University. She specializes in landform geomorphology in the solar system. As an associate member of the Cassini RADAR Team, she studies dunes, mountains, cryovolcanoes, rivers and lakes on Saturn's moon Titan, and she studies volcanoes and mountains on Jupiter's moon Io from Galileo, Cassini, and Voyager observations. Radebaugh has done field work in the Egyptian Sahara, the Ethiopian Afar Rift Valley, Hawaii, the desert southwestern US, and Antarctica.

Timothy Reckart is a Tucson attorney whose commercial and corporate practice focuses on intellectual property transactions and the representation of emerging-growth, technology-based companies. Reckart’s broad experience includes 22 years as General Counsel for technology-based enterprises, 19 of them with Research Corporation Technologies in Tucson. He holds a law degree and an MBA from Stanford University, a master’s degree in nuclear engineering from the University of California at Berkeley and a bachelor’s degree in nuclear engineering from the Massachusetts Institute of Technology.

Kjell Stakkestad is the President of Northstar, a wholly-owned subsidiary of KinetX Aerospace in Tempe, Arizona. He received both his bachelor and master degrees in mathematics from the University of California at Davis, and then accepted a position as a staff orbit analyst at Lockheed Missiles and Space Company (LMSC).  In 1993, Stakkestad left LMSC to help found KinetX Aerospace and serve as its first President and Chief Financial Officer.  As the orbit dynamics lead for the development of the IRIDIUM satellite ground control system, he developed the initial orbital dynamics requirements for the ground system.  He also led a variety of KinetX software, hardware, and system engineering projects for the IRIDIUM project. KinetX is a partner with LPL in the OSIRIS-REx mission.