48th Lunar and Planetary Science Conference (2017), Abstract #1507
E. Dunham, M. Wadhwa, R. Hervig, S. Simon, L. Grossman
47th Lunar and Planetary Science Conference (2016), Abstract #2723
Prajkta Mane received her B.Sc. in Geology from the University of Mumbai (St. Xavier’s College) in 2008, followed by her M.Sc. in Applied Geology from the Indian Institute of Technology (Bombay) in 2010.
After receiving her M.Sc., Prajkta worked as a Project Associate at PLANEX Physical Research Laboratory in Ahmedabad India, a unit of the Government of India’s Department of Space. Her work involved analyzing the isotopic composition of calcium- and aluminum-rich inclusions (CAIs) in meteorites via Multi Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICP-MS).
Prajkta’s research in the Center for Meteorite Studies focuses on determining the chemical and isotopic compositions of meteorites in order to shed light on processes in the early Solar System. She analyzes CAIs to decipher the chronology of early Solar System events and the specific processes involved; CAIs were the first solids to condense from the Solar nebula, and they preserve petrographic and geochemical records of the earliest events to shape our Solar System.
The inclusions Prajkta studies are encapsulated by distinct edges, composed of only one or two minerals, called Wark-Lovering rims. Due to the extremely small scale of these rims, it is challenging to analyze their chemical and isotopic composition with traditional mass spectrometry techniques. Using the Cameca NanoSIMS 50L at ASU, Prajkta has been able to chemically image Wark-Lovering rims on a nanometer scale via secondary ion mass spectrometry, and has successfully age-dated them using their aluminum and magnesium isotopic content. The results of her analyses have provided insight into the chronology of events in the early Solar System and the accretion of planetary bodies, and Prajkta plans to continue her study of primitive meteorites to further constrain the formation time of these rims.
In addition to her work on Wark-Lovering rims, Prajkta has measured zirconium isotopes in CAIs, and has investigated the evolution of water reservoirs on Mars using the hydrogen isotope composition of the newest martian meteorite fall, Tissint.
Prajkta is a recipient of NASA’s Earth and Space Science Fellowship, and was granted the 2014 Graduate Excellence Award by ASU’s College of Liberal Arts and Sciences.
An active participant in outreach activities, Prajkta frequently represents the Center for Meteorite Studies and School of Earth and Space Exploration at events such as ASU Homecoming, Earth & Space Open House, Night of the Open Door, and Phoenix Comicon.
Having successfully defended her dissertation in September, Prajkta plans to pursue a career in meteoritics and planetary science. She has a strong interest in pioneering analytical methods to significantly advance our knowledge of the building blocks of the Solar System, in particular the development of laboratory techniques to further study the isotope geochemistry of meteorites and samples returned from planetary missions.
Karen Rieck received her M.S. from Arizona State University in 2008. As a Master’s student, she measured lithium isotopes in basaltic meteorites. Supervised by Dr. Richard Hervig, the goal of this research was to better understand the thermal histories of eucrites by measuring chemical heterogeneity within the minerals comprising these basaltic meteorites.
During her Ph.D. in the School of Earth & Space Exploration, Karen conducted scientific research on Solar System materials under the advisement of her committee members (Richard Hervig, Thomas Sharp, Meenakshi Wadhwa, Peter Williams, Patrick Young, and Amy Jurewicz).
Her primary project centered on quantifying the abundances of sodium and potassium in the solar wind. To do this, she used secondary ion mass spectrometry (SIMS) to measure samples of solar wind returned by NASA's Genesis spacecraft. This information will help to constrain the baseline composition of the protoplanetary disk from which our Solar System formed. Solar wind samples are a good surrogate for the solar nebula because (1) a preponderance of scientific evidence suggests that the outer layer of the Sun preserves the composition of the early solar nebula, and (2) spacecraft measurements suggest that, for most rock-forming elements, the process of solar wind ejection from the Sun does not appear to cause significant fractionation of elements.
As a secondary project, Karen investigated microtextural changes associated with olivine phase transformation as a function of water content, using optical microscopy, Raman, and scanning electron microscopy, in order to clarify and constrain phase transformation processes in Earth's mantle.
She also utilized optical microscopy and image processing software to investigate ilmenite abundance & crystal size distribution in Apollo 17 Lunar Samples. The information gleaned from this research will enable better interpretation of remote sensing data from orbiting spacecraft.
Karen is the recipient of three NASA Earth and Space Science Fellowships, awarded to outstanding students pursuing graduate degrees in basic and applied research in Earth and space sciences.
Taking an active interest in geology education and outreach, Karen has served as Secretary, Vice-President, and Outreach Coordinator for the ASU Geology Club. She has also participated in numerous outreach events with the Center for Meteorite Studies, including the annual Earth & Space Exploration Day, and ASU’s Night of the Open Door.
Having successfully defended her doctoral dissertation in October, 2015, Karen has undertaken a post-doctoral scholarship at Los Alamos National Laboratory, where she will continue analyzing Genesis solar wind samples.
Kera Tucker received her B.S. in Geology from Oregon State University in 2011. As an undergraduate student, Kera worked with Dr. Anita Grunder on the geochemical classification of pumices found in Oregon’s Hampton Tuff ignimbrite. The results of this research were presented at the 2011 Geological Society of America’s Rocky Mountain and Cordilleran Joint Meeting in Logan, Utah.
After completing her undergraduate degree, Kera became a Program Specialist with the NASA Astrobiology Institute, and was involved in various education and public outreach efforts including FameLab and NASA Ames team public outreach, as well as social media, and Astrobiology Institute datasets.
Excited to combine her passions for geology and space science, Kera enrolled as a Master’s student in the School of Earth and Space Exploration at ASU in 2013. Her Master’s project was aimed at determining the hydrogen isotopic composition and water content of the interior of Mars by analyzing Nominally Anhydrous Phases (NAPs) in eight martian meteorites. She performed this work under the supervision of Prof. Meenakshi Wadhwa (Director, Center for Meteorite Studies), and in collaboration with Profs. Richard Hervig and Christy Till.
Using the Secondary Ion Mass Spectrometer (SIMS) at Arizona State University, Kera conducted 113 individual analyses of water content and hydrogen isotopic composition of NAPs in the shergottites Zagami, Los Angeles, QUE 94201, SaU 005 and Tissint and in the nakhlites Nakhla, Lafayette, and Yamato 000593. Based on these analyses, Kera was able to infer that the mantle source reservoirs of the martian meteorites were similar to the Earth’s mantle in terms of hydrogen isotopic composition and water content.
A portion of Kera's thesis study was recently presented at the 46th Lunar and Planetary Science Conference, in Houston, TX (read Kera's conference abstract here). Having successfully defended her Master’s thesis in April of 2015, Kera will graduate in May.
Kera aspires to a career in field geology, allowing her to pursue her passions for Earth Science and the outdoors, as well as providing the opportunity to inspire and educate future generations.