2012 Annual Science Report

Rensselaer Polytechnic Institute Reporting  |  SEP 2011 – AUG 2012

EPO Activity: Undergraduate Research in Astrobiology

Project Progress

Astrobiology research projects for a total of 18 undergraduates were carried out under the mentorship of NAI faculty during the reporting period. The contributions of all undergraduates are summarized below, in order of the projects they were associated with (see also separate sections).

Project 1: Interstellar Origins of Preplanetary Matter (4 Rensselaer students)
Steven Lentine, Cale Kochenour (Physics) and Marshall Aiken (Interdisciplinary Science) analyzed spectroscopic data from two NASA observational facilities, the Spitzer Space Telescope and the ground-based Infrared Telescope Facility (IRTF). The merged Spitzer and IRTF data provide coverage of absorption features in different constituents of interstellar and circumstellar dust and ices, and results enable us to compare the chemical and thermal evolution of ices in the environments of young stellar objects of different luminosity and mass. Lentine is lead author of a journal article that is in an advanced stage of preparation for publication.

Varun Bajaj (Physics) has begun a project in collaboration with NAI postdoc Charles Poteet to model spectra from the Spitzer archive using laboratory data for ices and silicates in combination with models for the underlying stellar atmospheres.

Project 2: Processing of Precometary Ices in the Early Solar System (2 Rensselaer students)
Nicholas Senno and Will Cunningham (Physics) carried out molecular dynamics simulations to study the possible alignment of chiral molecules in supersonic flows. The ultimate goal of this research initiative is to determine whether the chiral asymmetry observed in meteoritic amino acids was related to the effects of shock waves and other supersonic flows in the environments where they formed.

Project 3: Impact History of the Earth-Moon System (2 Albion College students)
Holly Farris (Physics) began selecting Apollo 15 impact glasses in Spring 2012, a project started by Zellner during her sabbatical in Fall 2011 at the Australian National University in Canberra. Though funded by Zellner’s NSF and NASA grants, this research complements Project 3 of this NAI award. Holly is now a first-year planetary science graduate student in the Department of Physics at the University of Arkansas.

Alysandra Ganem (Physics) worked with Zellner in Summer 2012 on a lunar imaging and spectroscopy project, using the 14” Celestron and 10” Meade telescopes at Albion College. Funded by Albion College’s Foundation for Undergraduate Research, Scholarship, and Creative Activity (FURSCA), Alysandra began learning about the Moon’s formation and history, as well as about its geological features, including the impact basins and craters. This project was designed to serve as a precursor that will allow undergraduate students to participate in Project 3 of this NAI award.

Project 4: Survival of Sugars in Ice/Mineral Mixtures on High Velocity Impact (3 Albion College students)
Erica Earl (Chemistry) worked with McCaffrey in summer 2012 to understand the chemistry of unshocked GLA on the surface of montmorillonite clays in liquid solution. Erica continues to work with us during this academic year. Casey Waun (Chemistry) worked with Gudipati at JPL, using MALDI to obtain mass spectra of unshocked and shocked GLA and DHA. Casey spent time learning the instrumentation and then figuring out how to optimize the sample spectra. Though it has yet to be determined whether or not new molecules were found in the shocked samples by MALDI, Casey reports that “a significant number of spectra have been collected and further analysis can continue to occur.” Casey is continuing this project at Albion College and is developing it into her thesis for graduation with Department Honors.

Kelsi Blauvelt worked with Gudipati at JPL, customizing LABVIEW programming to interface the software of the MADLI stepper motors so that they could move independently in the x-, y-, and z-directions, as indicated by user input. Of her summer experience, Kelsi reports: “Being at JPL…reinforced my interest in Physics and made me realize that my next step needs to be graduate school so that I can further my knowledge for novel research… I was also lucky enough to be working at JPL during the MSL landing, and to see the way the facility operates during a mission was a wonderful experience… I was extremely happy with my internship experience and very much appreciate the opportunity to work at JPL.”

Project 6: The Environment of the Early Earth (2 Rensselaer students)
Sebastian Mergelsberg (dual Geology/Biology major) continued his experiments aimed at evaluating the uptake of small amounts of possible atmospheric gases in rock-forming minerals. As described in our NAI proposal, the general rationale of this study was to explore the possibility that ancient minerals (e.g., quartz from the Jack Hills locality containing Hadean zircons) might retain a record of volatile species present in the crystallization environment. Sebastian demonstrated that carbon is incorporated in small amounts in quartz and in apatite. In addition, Sebastian obtained preliminary data on S uptake in apatite, and was able to place constraints on the diffusion rates of all species in the respective minerals. These are sufficiently slow to potentially preserve a record of their abundance in ancient minerals. Sebastian participated in NYCA research for 3 years through Rensselaer’s Undergraduate Research Participation (URP) program; he is now a doctoral student at Virginia Tech.

Ian McCusker (Geology major) conducted a reconnaissance study of Hadean Jack Hills zircon using optical microscopy and electron microprobe analyses, with the broad goal of cataloging mineral inclusions and identifying possible high-temperature zircons. With NAI post-doc Dustin Trail, Ian also participated in the development of Rensselaer’s laser-ablation ICP-MS for age determinations of zircons using U and Pb isotopes, which is now routine. Ian is senior this year and will continue his involvement with the NYCA during the present academic year through the URP program.

Project 7: Prebiotic Chemical Catalysis on Early Earth and Mars (3 Rensselaer students)
Rachel Mathew (Biophysics/Biochemistry major) pursued a research project with Ingrid Wilke in Spring and Summer 2012. She is continuing her research in Fall 2012. Her research involved the fabrication of thin (< 1mm), flat and mechanically stable (free standing) disks of montmorillonite with diameters of 8-12 mm. In the project two different approaches of disk fabrication were pursued: (a) Disk fabrication by pressing montmorillonite powder into flat pellets with a hydraulic press, and (b) disk fabrication by self-assembly of montmorillonite platelets during drying from suspensions. Approach (a) results in montmorillonite disks with random orientation of the montmorillonite microcrystals. In contrast, approach (b) results in montmorillonite disks with an ordered microstructure. Approach (a) has been successfully implemented and permits the reproducible fabrication of montmorillonite disks with the desired dimensions and mechanical stability. Approach (b) resulted in the successful fabrication of a first prototype. Further research will be focused on refinement of approach (b) and demonstrating reproducible sample fabrication. Rachel reported her results in an oral presentation in a group meeting and a written internal report.

Connor Schleicher and Andrew Tupper (Chemistry) worked with James Ferris, Prakash Joshi and Michael Aldersley in the clay catalysis laboratory. Connor investigated the role of different mineral salts on the montmorillonite catalyzed prebiotic RNA synthesis. These minerals are known to facilitate hydrophilic and hydrophobic interactions in organic reactions. Andrew processed clay minerals obtained worldwide for chemical analysis and testing of catalytic activity in RNA synthesis. His work involved treatment of raw clay samples with dilute acid and water to form acid clay, which was converted into neutral (pH 7) clay by titration with NaOH. The neutral clay samples are being tested routinely for catalytic activity in prebiotic RNA synthesis.

Project 8: Microenvironmental Influences on Prebiotic Synthesis (2 Rensselaer students)
Elizabeth Moriarty (Chemistry) worked with graduate student mentor Lauren Cassidy. She prepared solutions containing GMP alone and mixed with other ribonucleotides. The goal is to understand how the reversible self-association of GMP to form organized structures and gel phases, which would compete with its incorporation into abiotically polymerized RNA, would affect the emergence of RNA on prebiotic Earth. She collected circular dichroism (CD) spectra of the various solutions and gel phases for structural characterization and performed thermal melts to investigate their thermal stability and reversibility. Elizabeth graduated in Spring 2012.

Elisa Novelli (Chemistry) worked with graduate student mentor Bradley Burcar. She performed abiotic RNA polymerization reactions on catalytic clays and analyzed the products using MALDI Mass Spectrometry. The goal of the project is to understand how to correctly interpret the information in the mass spectra and to determine the effects of various chemicals and conditions on the abiotic RNA polymerization products. Eliza plans to continue her research until her graduation in Spring 2013.