nai

Project Progress

SUMMER UNDERGRADUATE INTERNSHIPS IN ASTROBIOLOGY

Project Investigators: Michael Mumma, Drake Deming, Jason Dworkin, Jennifer Eigenbrode, Marla Moore, Geronimo Villanueva, and Richard Walker

2008 featured the fifth SUIA offering (Summer Undergraduate Internships in Astrobiology), a ten-week residential research program at the Goddard Center for Astrobiology (GCA). (http://astrobiology.gsfc.nasa.gov/education.html) Competition was very keen, with an oversubscription ratio of 3.0. Students applied from over 28 colleges and universities in the United States, and 6 Interns from 4 institutions were selected. Each Intern carried out a defined research project working directly with a GCA scientist at Goddard Space Flight Center or the University of Maryland. As a group, the Interns met with a different GCA scientist each week, learning about his/her respective area of research, visiting diverse laboratories and gaining a broader view of astrobiology as a whole. During a Field Trip to the National Radio Astronomy Observatory in Greenbank, West Virginia, Interns toured the Telescope Operations Facility that monitors and controls the Robert C. Byrd Green Bank Telescope (GBT). The GBT is the most technically advanced single-dish radio telescope in the world. Its 110-meter by 100-meter dish boasts more than two acres of area for collecting faint radio waves from the Universe. Weighing 17 million pounds, the GBT is also one of the world’s largest moving structures on land. The Interns also took a class on how to operate the 40ft Telescope and were able to take observations and present their results the next day. At summer’s end, each Intern reported his/her research in a power point presentation projected nation-wide to member Teams in NASA’s Astrobiology Institute, as part of the NAI Forum for Astrobiology Research (FAR) Series.

(http://astrobiology.nasa.gov/nai/seminars/detail/128)

Brief Summaries of Research are given below:

Charlotte Carlstrom (Emory College) was mentored by GCA Collaborator Dr. Jen Eigenbrode (GSFC). Using standards and samples, Charlotte learned the fundamentals of gas chromatography mass spectrometry (GCMS) analysis of organic compounds common to Mars analog samples. First she prepared standard mixes of compounds common to terrestrial life (e.g. saturated, unsaturated, and hydroxy carboxylic acids, alphatic alcohols and ketones, amines, quinones, triglycerides, etc). These mixes are being used as a quantitative and qualitative reference for gas chromatography mass spectrometry (GCMS) analyses of Mars analog rocks and ice. Building upon Charlotte’s biological background and astrobiology interests, she also investigated a variety of hydrocarbons in control samples (snow algae and cryoconite sediments) from the surface of an arctic glacier that is the target of more intensive studies of signatures of life in ice (funded by NASA Programs in Exobiology and Mars Fundamental Research, J. Eigenbrode, PI). She compared GCMS results of (1) solvent-extracts, as is common of geobiology laboratories, and (2) pyrolysis products, as would be expected of an instrument similar to the Science Analysis at Mars (GCMS) being prepared by P. Mahaffy and colleagues for the Mars Science Laboratory mission. Her results shed light on molecular inputs to ice from surface biology, aerosols and wind-blown detritus. The results will contribute to a growing knowledge base of biosignatures from GCMS analyses, and will help us differentiate sources for trace levels of organics detected surface glacial ice.

Ariel Lewis (Eckerd College) was a second year intern and she worked with GCA Co-Investigator Dr. Jason Dworkin (GSFC). In their search for amino acids in meteorites, Dr. Dworkin and collaborators had identified ubiquitous contamination of samples collected in Antartica and stored in nylon bags. Ariel conducted a study of candidate collection bags for possible use in future Antarctic meteorite expeditions. Her work focused on finding a cleaner bag for meteorite collection and storage. Clean water samples were placed in bags made of three candidate materials and extracted twentyfour hours later. These samples were then subjected to acid hydrolysis and analyzed for contaminants using LC-FD/ToF-MS. This quantitative analysis allowed direct comparison of the amino acid cleanliness of the various bags, and identified a better bag for meteorite collection.

Lorne Loudin (Keene State College) worked with GCA Co-Investigator Prof. Richard Walker (University of Maryland) for a second summer. He investigated Os isotopic compositions and the concentrations of highly siderophile elements in multiple pieces of an Apollo 17 lunar impact melt rock: Highly Siderophile Elements and Osmium Isotope Systematics in the Lunar Impact Melt 76055. This work led to identification of surviving isotopic signatures of the impactor that created the Serentitatis Basin and also likely the relict signature of a pre-Serenitatis impactor. This is the first time such complexity has been observed in lunar impact melt rocks. Lorne plans to begin Graduate Studies in the Department of Geology, at the University of Maryland, working with Dr. Walker, in January 2009.

Nadezhda Radeva (Connecticut College) is a second year intern and was mentored by GCA Collaborator Dr. Geronimo Villanueva (GSFC). Nadya analyzed high resolution infrared spectra of Mars acquired at the W. M. Keck Observatory (Mauna Kea, HI), emphasizing bands of CO₂, H₂O, HDO, and O₂ revealed in a spectrally complete survey of the 1.1-1.4, 2.9-3.7, and 4.6-5.0 μm spectral regions. Working with these highly advanced spectra, she studied and removed instrumental effects (e.g., hot and dead pixels, spectral-fringes, spectral tilt, and baseline offsets) and provided calibrated spectra across the disk of Mars. She extracted line intensities for water (H₂O) and O₂(1Δ) point-by-point along the central meridian of Mars, showing that the two species are anti-correlated on the planet. The O₂ emission is a tracer for ozone so her results provide a direct measure of these photo-chemically linked atmospheric species on Mars.

Lily Raines (Eckerd College) was mentored by GCA Co-Investigator Dr. Marla Moore (GSFC), on a project entitled “Following the carbon: Structure, Chemistry and Spectroscopy of Frozen Ethane”. Oort Cloud comets, as well as Pluto, Quaoar, 2005 FY9, and other TNOs contain significant amounts of ethane. Even though this molecule is found in many places, there is very little information about its amorphous, metastable, and crystalline phases. Lily’s experiments formed ethane ices at various temperatures, then heated and ion-irradiated them to investigate the resulting phase changes, the possible reversal of phase changes, and the radiation chemistry of ethane. These properties were studied using IR spectroscopy in the near-, mid-, and far-IR regions. Improved understanding of ethane ices and processing may contribute to future searches for related hydrocarbons in the outer solar system.

Kamen Todorov (Connecticut College) was mentored by GCA Co-Investigator Dr. Drake Deming (GSFC). Kamen’s presentation was on the Atmosphere of Exoplanet HAT-P-1b from Spitzer Space Telescope Observations. HAT-P-1b is a transiting gas giant planet orbiting extremely close to its parent star. It is a typical representative of the class of 'hot Jupiters’. Kamen analyzed data from the secondary eclipse of HAT-P-1b in four different wavelengths. He detected the flux from the planet and compared it with existing models of planetary atmospheres; the results are being prepared for publication. This was Kamen’s second year as an intern and he will begin graduate studies at Penn State in the fall of 2008.