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Project Reports

• Advancing Methods for the Analyses of Organics Molecules in Microbial Ecosystems

  Eigenbrode’s GCA work over the past year has largely focused on advancing protocols for the extraction and analysis of complex organics molecules in iron-oxide rich samples regarded as analogs to groundwater seeps and ancient surface water environments on Mars and ancient Earth. Eigenbrode has succeeded with some advance in methods for organic extraction and analysis for samples that include iron seep sediments, cultured iron bacteria, and terrace sediments of the Rio Tinto. In addition, Eigenbrode has been part of a successful study aimed at understanding microbial metabolisms and ecological evolution of Neoarchean using Fe, S, and C isotopic records.

  ROADMAP OBJECTIVES: 2.1 4.1 5.1 5.2 5.3 6.1 7.1

• Composition of Parent Volatiles in Comets: Oxidized Carbon

  GCA Co-Investigator Dr. Michael DiSanti continued his work on measuring parent volatiles in comets using high-resolution near-infrared spectroscopy at world class observatories in Hawai’i and Chile. The goal of this work is to build a taxonomy of comets based on ice compositions, which show considerable variation among comets measured to date. DiSanti’s research emphasizes the chemistry of volatile oxidized carbon, in particular the efficiency of converting CO to H2CO and CH3OH on the surfaces of icy interstellar grains, through H-atom addition reactions prior to their incorporation into comets. The work requires planning and conducting observations, processing of spectra, and development and application of fluorescence models for interpretation of observed line intensities.

  ROADMAP OBJECTIVES: None Selected

• Chemical Models of Nebular Processes

  We have conducted theoretical and observational studies to understand the chemical transformation of matter as it evolves between different astronomical environments: from interstellar molecular clouds to protoplanetary disks and comets. Theoretical work has focused on isotopic fractionation processes and negative ion chemistry. Observational work has involved a campaign to observe comet C/2007 N3 (Lulin) at milllimeter wavelengths, as well as interferometric mapping of the Orion-KL star-forming region and the IRS 46 protoplanetary disk.

  ROADMAP OBJECTIVES: None Selected

• Origin and Evolution of Organics in Planetary Systems

  The central goal of the Blake group effort in the NASA GSFC Astrobiology node (Origin and Evolution of Organics in Planetary Systems (Mike Mumma, P.I.) is to determine whether complex organics such as those seen in meteorites are detectable in the circumstellar accretion disks that encircle young stars and in the comae of comets. Our program has both observational and laboratory components. We use state-of-the-art telescopes from microwave to optical frequencies, and we have developed novel high frequency and temporal resolution instruments that seek to utilize the unique properties of the terahertz (THz) modes of complex organics. The astronomical searches for such modes will begin with Herschel PACS and HIFI observations in early 2010, and will continue with SOFIA and ALMA studies as these observatories become operational in CY2011 and CY2012. The overall suite of laboratory and observational research promises to revolution our understanding of prebiotic chemistry in both our own and other solar systems.

  ROADMAP OBJECTIVES: 1.1 1.2 3.1

• Research Activities in the Astrobiology Analytical Laboratory

  A little over 4.5 billion years ago, our solar system was a disk of gas and dust, newly collapsed from a molecular cloud, surrounding a young and growing protostar. Today most of the gas and dust is in the spectacularly diverse planets and satellites of our solar system, and in the Sun. How did the present state of the planetary system come to be from such undistinguished beginnings? The telling of that story is an exercise in forensic science. The “crime” occurred a long time ago and the “evidence” has been tampered with, as most planets and satellites display a rich variety of geological evolution over solar system history.

  Fortunately, not all material has been heavily processed. Comets and asteroids represent largely unprocessed material remnant from the early solar system and they a represented on Earth by meteorites and interplanetary dust particles (IDPs). Furthermore, telescopic studies of the birth places of other solar systems allow researchers to simulate those environments in the laboratory so that we may characterize the organic material produced.

  We are a laboratory dedicated to the study of organic compounds derived from Stardust and future sample return missions, meteorites, lab simulations of Mars, interstellar, proto-planetary, and cometary ices and grains, and instrument development. Like forensic crime shows, the Astrobiology Analytical Laboratory employs commercial analytical instruments. However, ours are configured and optimized for small organics of astrobiological interest instead of blood, clothing, etc.

  ROADMAP OBJECTIVES: 3.1 4.3 7.1

• Summer Undergraduate Internships in Astrobiology

  2009 featured the sixth SUIA offering (Summer Undergraduate Internships in Astrobiology), a ten-week residential research program at the Goddard Center for Astrobiology (GCA).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

  ROADMAP OBJECTIVES: None Selected

• The Formation of Graphite Whiskers in the Primitive Solar Nebula

  Graphite whiskers have been discovered associated with high temperature phases in meteorites1 such as Calcium Aluminum Inclusions and chondrules and it has been suggested that expulsion of such material from protostellar nebulae could significantly affect the optical properties of the average interstellar grain population. We have experimentally studied the potential for Fischer-Tropsch and Haber-Bosch type reactions to produce organic materials in protostellar systems from the abundant H2, CO and N2 reacting on the surfaces of available silicate grains2. When graphite grains are repeatedly exposed to H2, CO and N2 at 875K abundant graphite whiskers are observed to form on or from the surface of the graphite grains. In a dense, turbulent nebula such extended whiskers are very likely to be broken off and the fragments could be ejected either in polar jets or by photon pressure.

  ROADMAP OBJECTIVES: 3.1

• Accomplishments of Graduate Student Yana L. Radeva

  During the time period July 1, 2008 – June 30, 2009, Yana L. Radeva who is a fifth year Ph.D. Student in the Department of Astronomy at the University of Maryland refined and finalized her analysis of the organic composition of comet C/2000 WM1 (LINEAR). The comet was observed with the Near Infrared Echelle Spectrograph on the Keck II telescope on 23, 24 and 25 Nov. 2001.

  ROADMAP OBJECTIVES: None Selected

• Advancing Techniques for in Situ of Complex Organics

  During this year we continued developing techniques and protocols for laser time-of-flight mass spectrometry (TOF-MS) analysis of complex organic molecules and trace elements, which would be of importance on missions to Mars, Titan, comets, and other planetary bodies, where resources for chemical sample manipulation, preparation, and processing are limited. We upgraded the solid sampling and optical configurations for our “Tower TOF” prototype and used the system to further develop peak pattern libraries for Mars and cometary analogs in comparison with other instrument techniques. We examined the effects of sample preparation on fragmentation patterns of benzene di-, tri-, and hexa-carboxylic acid standards, finding that often simpler approaches can yield more reliable results. We also worked toward a new laser pyrolysis-based experiment for analysis of neutral gas from solid samples.

  ROADMAP OBJECTIVES: 2.1 2.2 7.1

• Astrobiology Progress Report

  Scientists at the Cosmic Ice Laboratory with the Goddard Center for Astrobiology study the formation and stability of molecules under conditions found in outer space. During the past year, amino acids found in meteorites were investigated, including some acids not found in terrestrial biology. Investigations into the photostability of glycine under Martian conditions, and environments in the outer solar system, were begun. A project on ethane ice’s spectra and chemistry was initiated. All of this work is part of the Comic Ice Laboratory’s continuing contributions to understanding the chemistry of biologically-related molecules and chemical reactions in extraterrestrial environments.

  ROADMAP OBJECTIVES: 3.1 3.2 7.1

• Current Status & Future Bioastronomy With the Large Millimeter Telescope

  Irvine and colleagues at the University of Massachusetts have been using a unique new broadband radio receiver to measure the spectra of external galaxies in the 3mm wavelength region, and hence to study the chemistry of their interstellar gas. The so-called Redshift Search Receiver allows the simultaneous observation of essentially the entire 3mm spectrum of a galaxy, and hence to measure the molecular emissions in this band. Including all the 10 galaxies observed, we detected 20 spectral lines from 14 different atomic and molecular species. There are interesting differences in the chemistry of these objects, e.g., in the relative strength of emission lines from HCN, HNC, HCO+, CH3OH, 13CO , CS and N2H+ (a proxy for N2). The receiver is ultimately intended for use on the Large Millimeter Telescope; however, until the LMT is completed, the receiver has been tested at the Five College Radio Astronomy Observatory’s 14-meter telescope, operated by the University of Massachusetts Amherst.

  ROADMAP OBJECTIVES: 2.2 3.1

• Evolution of Protoplanetary Disks

  Drs. Aki Roberge and Carol Grady are pursuing studies related to Theme 2 of the NASA GSFC Astrobiology Node, “From Molecular Cores to Planets: Our Interstellar Heritage.” Over the last year, they have been preparing for two Open Time Key Projects using the recently launched Herschel Space Observatory. Herschel is expected to spearhead the next big advances in our knowledge of planet formation, protoplanetary disk evolution, and debris disks. One project (GASPS) will illuminate the evolution of gas abundances and chemistry in protoplanetary disks over the planet-forming phase. The other (DUNES) will sensitively probe the Sun’s nearest neighbors for signs of extrasolar Kuiper Belts. Dr. Roberge has also been working on plans for future direct observations of potentially habitable terrestrial planets.

  ROADMAP OBJECTIVES: None Selected

• Fingerprinting Late Additions to the Earth and Moon via the Study of Highly Siderophile Elements in Lunar Impact Melt Rocks

  Lunar impact melt rocks have been examined for absolute and relative abundances of the highly siderophile elements. This suite of iron-loving elements can potentially be used to fingerprint the large impactors that struck the Earth and Moon during late stages of bombardment. Results for a variety of Apollo and meteoritic impact melt rocks suggest that some impactors were similar to chondritic meteorites but others were not, suggesting an origin via a type of impactor that is no longer sampled by the Earth. Synthesis of these data, as well as data for terrestrial and martian mantle suggests that late accretion was involved in the establishment of the abundances of these elements in their planetary mantles, but could not have been the only process. Pristine lunar crust has very low abundances of all HSE and cannot account for any of the inter-element variations that have been recorded in some lunar impact melt rocks.

  ROADMAP OBJECTIVES: 1.1

• NASA Postdoctoral Program Research Summary

  We used the Swift observatory to study the gaseous composition and evolution of two very interesting comets (8P/Tuttle and C/2007 Lulin). The spectral ranges of Swift’s grisms (175-520 nm) encompass known cometary fluorescence bands of OH (306 nm), and of many other molecular fragments (e.g., NH, CS, CN, C2, fragment CO, etc.). Repeated observations of the two comets with Swift’s UV-Optical Telescope provided a unique dataset that reveals variations in the comet’s gas production rate on a scale of hours as well as months. As part of this investigation, much time and effort was dedicated to developing new analytical routines for processing the grism data. Further observations of different comets will provide insight in the chemical connection between parent- and fragment molecules.

  ROADMAP OBJECTIVES: 3.1 3.2

• Origin and Evolution of Organics in the Planetary Systems

  This progress report summarizes astrobiology research done during the past 12 months (July 2008 – June 2009) at Washington University in St. Louis under the direction of Professor Bruce Fegley, Jr. This research is part of the NASA Goddard Center for Astrobiology (GCA) Team.
  During the past year we (Professor Fegley and Ms. Laura Schaefer) worked on two related topics. These topics are (1) chemistry during metamorphism on chondrite parent bodies, (2) chemistry during accretion of the Earth and Earth-like planets. We published (or have in press) two refereed papers, two invited book chapters, and four abstracts. A third paper has been submitted to Icarus. A fourth paper, with French astronomers who discovered Corot 7-b is in preparation and will be submitted shortly. All ten publications are listed on the attached list.

  ROADMAP OBJECTIVES: 1.2 4.1

• X-Ray Emission From an Erupting Young Star and Stellar Population in the Carina Massive Star Forming Region

  High-energy photons in the young stellar environment are known to be important in stimulating chemical reactions of molecules and producing pre-biotic materials. In this reporting period, we studied X-ray emission from an erupting young star, young stars in a massive star forming region and a neutron star, whose ancient activity may affect current star formation. In particular, the Chandra and Suzaku observatories detected hard variable X-ray emission from the erupting young star V1647 Ori. This result suggests that the new eruption started in 2008 is driven by the same mechanism as an earlier eruption started in 2004.

  ROADMAP OBJECTIVES: 3.1