Dr. Perry A Gerakines

Dr. Perry A Gerakines

  • (AST, PLANETARY STUDIES)
  • 301.286.9179
  • NASA/GSFC
  • Mail Code: 691.1
  • Greenbelt , MD 20771
  • Employer: NASA
  • Brief Bio

    Research Interests

    Cosmic Ices

    I specialize in the study of interstellar and planetary ices. These include icy dust grain mantles found in dark interstellar clouds as well as icy materials found on the surfaces of objects within the outer Solar System (comets, icy moons, Kuiper Belt Objects, etc.).

    I have used spectroscopy in different regions of the electromagnetic spectrum, such as the infrared or ultaviolet, to study the compositions of astrophysically relevant materials. Lab data help to predict and interpret observations made with astronomical observatories (such as the Spitzer or James Webb Space Telescopes) and planetary missions (such as Cassini or New Horizons). I also create laboratory analogs of interstellar and solar-system ices in order to understand the physical and chemical changes they undergo when exposed to particle radiation or high-energy photons.

    Astrobiology

    In work supported by the Goddard Center for Astrobiology, I have studied the survivability of amino acids glycine, alanine, and phenylalanine in icy planetary subsurfaces subjected to particle radiation (Mars, Europa, comets).  This work has been highlighted in a NASA press release from 2013 and featured on the website of the NASA Astrobiology Institute.

    Spectroscopy of Astrophysical Ices

    This includes measurements of the infrared spectra of mixed molecular ices of astrophysical interest at temperatures from 10 to 300 K;  the determination of parameters such as complex refractive indices (optical constants), band intensities (band strengths) , and absorption coefficients. 

    Infrared Observational Astronomy

    Studies of dust and ice in the interstellar medium (ISM); Extinction and reddening of starlight by dust; Polarization of starlight in the ISM; Infrared absorption features due to interstellar dust and ice; the abundance of interstellar molecules in dust grain mantles; observations at international ground-based telescopes (such as the United Kingdom Infrared Telescope) and using space observatories (such as the Infrared Space Observatory and the Spitzer Space Telescope)

    Planetary Exploration and Missions

    I am a Deputy Project Scientist for the Comet Astrobiology Exploration SAmple Return (CAESAR) mission, a candidate for selection as the fourth mission in NASA’s New Frontiers Program. CAESAR would sample the surface of comet 67P/Churyumov-Gerasimenko and return the sample to Earth for detailed studies. It would be the farthest-reaching sample return mission in history. 

    Education

    1998 -- Ph.D., Physics, Rensselaer Polytechnic Institute (Troy, NY)
    1995 -- Two-year Research Degree (M.S.), Astronomy, Leiden University (Leiden, the Netherlands)
    1993 -- B.S., Physics (Astrophysics minor), Rensselaer Polytechnic Institute (Troy, NY)

    Positions/Employment

    9/2010 - Present

    Research Space Scientist

    NASA Goddard Space Flight Center, Greenbelt, MD
    10/2006 - 8/2012

    Associate Professor

    Department of Physics, the University of Alabama at Birmingham, Birmingham, AL
    9/2000 - 9/2006

    Assistant Professor

    Department of Physics, the University of Alabama at Birmingham, Birmingham, AL
    11/1998 - 8/2000

    Postdoctoral Research Associate

    National Research Council - National Academy of Sciences, NASA Goddard Space Flight Center, Greenbelt, MD

    Professional Societies

    American Astronomical Society (AAS), 1993 - Present
    Division for Planetary Sciences
    Laboratory Astrophysics Division
    American Geophysical Union (AGU), 1999 - Present
    International Astronomical Union (IAU), 2002 - Present
    American Association for the Advancement of Science (AAAS), 2016 - Present
    Society of Physics Students (SPS), 1995 - Present
    Asia-Oceania Geosciences Society (AOGS), 2005 - Present
    American Chemical Society (ACS), 1998 - 2014

    Other Professional Information

    For a complete listing of my publications and presentations, see the results of a Harvard ADS Query for the author name "Gerakines".

    Also see my ResearcherID Profile.

    Selected Publications

    Refereed

    Hudson, R. L., P. A. Gerakines, and R. F. Ferrante. 2018. "IR spectra and properties of solid acetone, an interstellar and cometary molecule." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 193: 33-39 [10.1016/j.saa.2017.11.055]

    Loeffler, M. J., M. H. Moore, and P. A. Gerakines. 2016. "The Effects of Experimental Conditions on the Refractive Index and Density of Low-Temperature Ices: Solid Carbon Dioxide." The Astrophysical Journal, 827 (2): 98 [10.3847/0004-637x/827/2/98]

    Gerakines, P. A., and R. L. Hudson. 2015. "The radiation stability of glycine in solid CO2 – In situ laboratory measurements with applications to Mars." Icarus, 252: 466-472 [Full Text (Link)] [10.1016/j.icarus.2015.02.008]

    Hudson, R. L., P. A. Gerakines, and M. J. Loeffler. 2015. "Activation of weak IR fundamentals of two species of astrochemical interest in the Td point group – the importance of amorphous ices." Physical Chemistry Chemical Physics, 17 (19): 12545-12552 [Full Text (Link)] [10.1039/C5CP00975H]

    Gerakines, P. A., and R. L. Hudson. 2015. "Infrared spectra and optical constants of elusive amorphous methane." Astrophysical Journal Letters, 805 (2): L20 [Full Text (Link)] [10.1088/2041-8205/805/2/L20]

    Smith, K. E., P. A. Gerakines, and M. P. Callahan. 2015. "Metabolic precursors in astrophysical ice analogs: implications for meteorites and comets ." Chemical Communications, 51 (59): 11787-11790 [Full Text (Link)] [10.1039/C5CC03272E]

    Boogert, A. C., P. A. Gerakines, and D. C. Whittet. 2015. "Observations of the icy universe." Annual Review of Astronomy & Astrophysics, 53: 541-581 [Full Text (Link)] [10.1146/annurev-astro-082214-122348]

    Gerakines, P. A., and R. L. Hudson. 2015. "First infrared band strengths for amorphous CO2, an overlooked component of interstellar ices." The Astrophysical Journal Letters, 808 (2): L40 [Full Text (Link)] [10.1088/2041-8205/808/2/L40]

    Smith, K. E., M. P. Callahan, P. A. Gerakines, J. P. Dworkin, and C. H. House. 2014. "Investigation of pyridine carboxylic acids in CM2 carbonaceous chondrites: Potential precursor molecules for ancient coenzymes." Geochimica et Cosmochimica Acta, 136: 1-12 [Full Text (Link)] [10.1016/j.gca.2014.04.001]

    Hudson, R. L., P. A. Gerakines, and M. H. Moore. 2014. "Infrared Spectra and Optical Constants of Astronomical Ices: II. Ethane and Ethylene." Icarus, 243: 147-148 [10.1016/j.icarus.2014.09.001]

    Gerakines, P. A., and R. L. Hudson. 2013. "Glycine's Radiolytic Destruction in Ices: First in situ Laboratory Measurements for Mars." Astrobiology, 13: 647-655 [10.1089/ast.2012.0943]

    Callahan, M. P., P. A. Gerakines, M. G. Martin, Z. Peeters, and R. L. Hudson. 2013. "Irradiated benzene ice provides clues to meteoritic organic chemistry." Icarus, 226 (2): 1201-1209 [Full Text (Link)] [10.1016/j.icarus.2013.07.033]

    Gerakines, P. A., R. L. Hudson, M. H. Moore, and J.-L. Bell. 2012. "In-situ Measurements of the Radiation Stability of Amino Acids at 15 - 140 K." Icarus, 220: 647-659 [10.1016/j.icarus.2012.06.001]

    Richey, C. R., and P. A. Gerakines. 2012. "Near-infrared band strengths of molecules diluted in N2 and H2O ice mixtures relevant to interstellar and planetary ices." The Astrophysical Journal, 759: 74-86 [10.1088/0004-637X/759/1/74]

    Cook, A. M., D. C. Whittet, S. S. Shenoy, et al. P. A. Gerakines, D. W. White, and J. E. Chiar. 2011. "The Thermal Evolution of Ices in the Environments of Newly Formed Stars: The CO2 Diagnostic." The Astrophysical Journal, 730 (2): 124-138 [10.1088/0004-637X/730/2/124]

    Agresti, D. G., and P. A. Gerakines. 2009. "Simultaneous Fitting of Mars Moessbauer Data." Hyperfine Interactions, 188: 113-120 [10.1007/s10751-008-9896-1]

    Whittet, D. C., A. M. Cook, S. S. Shenoy, et al. J. E. Chiar, Y. J. Pendleton, and P. A. Gerakines. 2009. "The Nature of Carbon Dioxide Bearing Ices in Quiescent Molecular Clouds." The Astrophysical Journal, 695: 94-100 [10.1088/0004-637X/695/1/94]

    White, D., P. A. Gerakines, D. Whittet, and A. Cook. 2009. "Laboratory Spectra of the CO2 Bending-Mode Feature in Interstellar Ice Analogs Subject to Thermal Processing." Astrophysical Journal Supplement Series, 180: 182-191 [Full Text (Link)] [10.1088/0067-0049/180/1/182]

    Sonnentrucker, P., D. A. Neufeld, P. A. Gerakines, et al. E. A. Bergin, G. J. Melnick, W. J. Forrest, J. L. Pipher, and D. C. Whittet. 2008. "Fully Sampled Maps of Ices and Silicates in Front of Cepheus A East with Spitzer." The Astrophysical Journal, 672: 361-370.

    Whittet, D. C., S. S. Shenoy, E. A. Bergin, et al. J. E. Chiar, P. A. Gerakines, E. L. Gibb, G. J. Melnick, and D. A. Neufeld. 2007. "The abundance of carbon dioxide ice in the quiescent intracloud medium." The Astrophysical Journal, 655: 332-341.

    Abbas, M. M., D. Tankosic, P. D. Craven, et al. J. F. Spann, A. LeClair, E. A. West, J. C. Weingartner, A. G. Tielens, J. A. Nuth, R. P. Camata, and P. A. Gerakines. 2006. "Photoelectric Emission Measurements on the Analogs of Individual Cosmic Dust Grains." The Astrophysical Journal, 645:

    Gerakines, P. A., J. J. Bray, A. Davis, and C. R. Richey. 2005. "The Strengths of Near-Infrared Absorption Features Relevant to Interstellar and Planetary ices." The Astrophysical Journal, 620: 1140-1150.

    Bergin, E. A., G. J. Melnick, P. A. Gerakines, D. A. Neufeld, and D. C. Whittet. 2005. "Spitzer Observations of CO2 Ice Towards Field Stars in the Taurus Molecular Cloud." The Astrophysical Journal, 627: L33-L36.

    Gerakines, P. A., M. H. Moore, and R. L. Hudson. 2004. "Ultraviolet Photolysis and Proton Irradiation of Astrophysical Ice Analogs Containing Hydrogen Cyanide." Icarus, 170: 202-213.

    Gerakines, P. A., M. H. Moore, and R. L. Hudson. 2001. "Energetic Processing of Laboratory Ice Analogs: UV Photolysis vs. Ion Bombardment." JGR-Planets, 106: 33381-33386.

    Whittet, D. C., P. A. Gerakines, J. H. Hough, and S. S. Shenoy. 2001. "Interstellar Extinction and Polarization in the Taurus Dark Clouds: The Optical Properties of Dust near the Diffuse/Dense Cloud Interface." The Astrophysical Journal, 547: 872-884.

    Moore, M. H., R. L. Hudson, and P. A. Gerakines. 2001. "Mid- and Far-Infrared Spectroscopic Studies of the Influence of Temperature, Ultraviolet Photolysis, and Ion Irradiation on Cosmic-Type Ices." Spectrochimica Acta A , 57: 843-858.

    Hudson, R. L., M. H. Moore, and P. A. Gerakines. 2001. "The Formation of Cyanate Ion (OCN-) in Interstellar Ice Analogs." The Astrophysical Journal, 550: 1140-1150.

    Nummelin, A., D. C. Whittet, E. L. Gibb, P. A. Gerakines, and J. E. Chiar. 2001. "Solid Carbon Dioxide in Regions of Low-Mass Star Formation." The Astrophysical Journal, 558: 185-193.

    Wdowiak, T. J., P. A. Gerakines, D. G. Agresti, and S. J. Clemett. 2001. "Technology Considerations Relevant to an Exobiology Surface-Science Approach for Europa." Astrobiology, 1: 467-476.

    Gerakines, P. A., and M. H. Moore. 2001. "Carbon Suboxide in Astrophysical Ice Analogs." Icarus, 154: 372-380.

    Boogert, A. C., P. Ehrenfreund, P. A. Gerakines, et al. A. G. Tielens, D. C. Whittet, W. A. Schutte, E. F. van Dishoeck, T. de Graauw, L. Decin, and T. Prusti. 2000. "ISO-SWS Observations of Interstellar Solid 13CO2: Heated Ice and the Galactic 12C/13C Abundance Ratio." Astronomy & Astrophysics, 353: 349-362.

    Gerakines, P. A., M. H. Moore, and R. L. Hudson. 2000. "Carbonic Acid Production in H2O:CO2 ices UV Photolysis vs Proton Bombardment." Astronomy & Astrophysics, 357: 793-800.

    Gibb, E. L., D. C. Whittet, W. A. Schutte, et al. A. C. Boogert, J. E. Chiar, P. Ehrenfreund, P. A. Gerakines, J. V. Keane, A. G. Tielens, E. F. van Dishoeck, and O. Kerkhof. 2000. "An Inventory of Interstellar Ices toward the Embedded Protostar W33A." The Astrophysical Journal, 536: 347-356.

    Schutte, W. A., A. C. Boogert, A. G. Tielens, et al. D. C. Whittet, P. A. Gerakines, J. E. Chiar, P. Ehrenfreund, J. M. Greenberg, E. F. van Dishoeck, and T. de Graauw. 1999. "Weak Ice Absorption Features in the Spectrum of the Obscured Young Stellar Object W33 A." Astronomy & Astrophysics, 343: 966-976.

    Vandenbussche, B., P. Enhrenfreund, A. C. Boogert, et al. E. F. van Dishoeck, W. A. Schutte, P. A. Gerakines, J. E. Chiar, A. G. Tielens, J. V. Keane, D. C. Whittet, M. Breitfellner, and M. Burgdorf. 1999. "Constraints on the Abundance of Solid O2 in Dense Clouds from ISO-SWS and Ground-Based Observations ." Astronomy & Astrophysics, 346: L57-L60.

    Gerakines, P. A., D. C. Whittet, P. Ehrenfreund, et al. A. C. Boogert, A. G. Tielens, W. A. Schutte, J. E. Chiar, E. F. van Dishoeck, T. Prusti, F. P. Helmich, and T. de Graauw. 1999. "Observations of Solid Carbon Dioxide in Molecular Clouds with the Infrared Space Observatory." The Astrophysical Journal, 522: 357-377.

    Ehrenfreund, P., O. Kerkhof, W. A. Schutte, et al. A. C. Boogert, P. A. Gerakines, E. Dartois, L. dHendecourt, A. G. Tielens, E. F. van Dishoeck, and D. C. Whittet. 1999. "Laboratory Studies of Thermally Processed H2O-CH3OH-CO2 Ice Mixtures and their Astrophysical Implications." Astronomy & Astrophysics, 350: 240?253.

    Chiar, J. E., P. A. Gerakines, D. C. Whittet, et al. Y. J. Pendleton, A. G. Tielens, A. J. Adamson, and A. C. Boogert. 1998. "Processing of Icy Mantles in Protostellar Envelopes." The Astrophysical Journal, 498: 716-727.

    Whittet, D. C., P. A. Gerakines, A. G. Tielens, et al. A. J. Adamson, A. C. Boogert, J. E. Chiar, T. de Graauw, P. Ehrenfreund, T. Prusti, W. A. Schutte, B. Vandenbussche, and E. F. van Dishoeck. 1998. "Detection of Abundant CO2 Ice in the Quiescent Dark Cloud Medium toward Elias 16." The Astrophysical Journal, 498: L159-L163.

    Whittet, D. C., T. Prusti, G. A. Franco, et al. P. A. Gerakines, D. Kilkenny, K. A. Larson, and P. R. Wesselius. 1997. "On the Distance to the Chamaeleon I and II Associations." Astronomy & Astrophysics, 327: 1194-1205.

    Ehrenfreund, P., A. C. Boogert, P. A. Gerakines, A. G. Tielens, and E. F. van Dishoeck. 1997. "Infrared Spectroscopy of Interstellar Apolar Ice Analogs." Astronomy & Astrophysics, 328: 649-669.

    Whittet, D. C., A. C. Boogert, P. A. Gerakines, et al. W. A. Schutte, A. G. Tielens, T. de Graauw, T. Prusti, E. F. van Dishoeck, P. R. Wesselius, and C. M. Wright. 1997. "Infrared Spectroscopy of Dust in the Diffuse Interstellar Medium toward Cygnus OB2 No 12." The Astrophysical Journal, 490: 729-734.

    Schutte, W. A., P. A. Gerakines, T. R. Geballe, E. F. van Dishoeck, and J. M. Greenberg. 1996. "Discovery of Solid Formaldehyde toward the Protostar GL 2136: Observations and Laboratory Simulation." Astronomy & Astrophysics, 309: 633-647.

    Ehrenfreund, P., P. A. Gerakines, W. A. Schutte, M. C. van Hemert, and E. F. van Dsihoeck. 1996. "Infrared Properties of Isolated Water Ice." Astronomy & Astrophysics, 312: 263-274.

    Gerakines, P. A., W. A. Schutte, and P. Ehrenfreund. 1996. "Ultraviolet Processing of Interstellar Ice Analogs: Pure Ices." Astronomy & Astrophysics, 312: 289-305.

    Ehrenfreund, P., A. C. Boogert, P. A. Gerakines, et al. D. J. Jansen, W. A. Schutte, A. G. Tielens, and E. F. van Dishoeck. 1996. "A Laboratory Database of Solid CO and CO2 for ISO." Astronomy & Astrophysics, 315: L341-L344.

    de Graauw, T., D. C. Whittet, P. A. Gerakines, et al. O. H. Bauer, D. A. Beintema, A. C. Boogert, D. R. Boxhoorn, J. E. Chiar, P. Ehrenfreund, H. Feuchtgruber, F. P. Helmich, A. M. Heras, R. Huygen, D. J. Kester, D. Kunze, P. W. Morris, T. Prusti, P. R. Roelfsema, A. Salama, S. G. Schaeidt, W. A. Schutte, H. W. Spoon, A. G. Tielens, E. A. Valentijn, B. Vandenbussche, E. F. van Dishoeck, P. R. Wesselius, E. Wieprecht, and C. M. Wright. 1996. "SWS Observations of Solid CO2 in Molecular Clouds." Astronomy & Astrophysics, 315: L345-L348.

    van Dishoeck, E. F., F. P. Helmich, T. de Graauw, et al. J. H. Black, A. C. Boogert, P. Ehrenfreund, P. A. Gerakines, J. H. Lacy, T. J. Millar, W. A. Schutte, A. G. Tielens, D. C. Whittet, D. R. Boxhoorn, D. J. Kester, K. Leech, P. R. Roelfsema, A. Salama, and B. Vandenhussche. 1996. "A Search for Interstellar Gas-phase CO2 - Gas:Solid-State Abundance Ratios." Astronomy & Astrophysics, 315: L349-L352.

    Whittet, D. C., W. A. Schutte, A. G. Tielens, et al. A. C. Boogert, T. de Graauw, P. Ehrenfreund, P. A. Gerakines, F. P. Helmich, T. Prusti, and E. F. van Dishoeck. 1996. "An ISO-SWS View of Interstellar Ices: First Results." Astronomy & Astrophysics, 315: L357-L360.

    Schutte, W. A., and P. A. Gerakines. 1995. "Recent Results from the Leiden Observatory Laboratory: (a) Band Strengths in Mixed Ices; (b) UV Photolysis of Solid Methanol." Planetary & Space Science, 43: 1253-1256.

    Gerakines, P. A., and D. C. Whittet. 1995. "A Review of Interstellar Polarization Properties and Recent Measurements toward the Chamaeleon I and Taurus Dark Clouds." Planetary & Space Science, 43: 1325-1328.

    Gerakines, P. A., W. A. Schutte, J. M. Greenberg, and E. F. van Dishoeck. 1995. "The Infrared Band Strengths of H2O, CO, and CO2 in Laboratory Simulations of Astrophysical Ice Mixtures." Astronomy & Astrophysics, 296: 810-818.

    Gerakines, P. A., D. C. Whittet, and A. Lazarian. 1995. "Grain Alignment in the Taurus Dark Cloud." The Astrophysical Journal, 455: L171-L175.

    Greenberg, J. M., A. Li, C. X. Mendoza-Gomez, et al. W. A. Schutte, P. A. Gerakines, and M. de Groot. 1995. "Approaching the Interstellar Grain Organic Refractory Component." The Astrophysical Journal, 455: L177-L180.

    Whittet, D. C., P. A. Gerakines, A. L. Carkner, et al. J. H. Hough, P. G. Martin, T. Prusti, and D. Kilkenny. 1994. "A Study of the Chamaeleon-I Dark Cloud and T-Association - Part VI - Interstellar Polarization, Grain Alignment, and Magnetic Field." Monthly Notices of the Royal Astronomical Society, 268: 1-12.

    Brief Bio

    Selected Publications

    Refereed

    Hudson, R. L., P. A. Gerakines, and R. F. Ferrante. 2018. "IR spectra and properties of solid acetone, an interstellar and cometary molecule." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 193 33-39 [10.1016/j.saa.2017.11.055]

    Loeffler, M. J., M. H. Moore, and P. A. Gerakines. 2016. "The Effects of Experimental Conditions on the Refractive Index and Density of Low-Temperature Ices: Solid Carbon Dioxide." The Astrophysical Journal 827 (2): 98 [10.3847/0004-637x/827/2/98]

    Gerakines, P. A., and R. L. Hudson. 2015. "The radiation stability of glycine in solid CO2 – In situ laboratory measurements with applications to Mars." Icarus 252 466-472 [Full Text (Link)] [10.1016/j.icarus.2015.02.008]

    Hudson, R. L., P. A. Gerakines, and M. J. Loeffler. 2015. "Activation of weak IR fundamentals of two species of astrochemical interest in the Td point group – the importance of amorphous ices." Physical Chemistry Chemical Physics 17 (19): 12545-12552 [Full Text (Link)] [10.1039/C5CP00975H]

    Gerakines, P. A., and R. L. Hudson. 2015. "Infrared spectra and optical constants of elusive amorphous methane." Astrophysical Journal Letters 805 (2): L20 [Full Text (Link)] [10.1088/2041-8205/805/2/L20]

    Smith, K. E., P. A. Gerakines, and M. P. Callahan. 2015. "Metabolic precursors in astrophysical ice analogs: implications for meteorites and comets ." Chemical Communications 51 (59): 11787-11790 [Full Text (Link)] [10.1039/C5CC03272E]

    Boogert, A. C., P. A. Gerakines, and D. C. Whittet. 2015. "Observations of the icy universe." Annual Review of Astronomy & Astrophysics 53 541-581 [Full Text (Link)] [10.1146/annurev-astro-082214-122348]

    Gerakines, P. A., and R. L. Hudson. 2015. "First infrared band strengths for amorphous CO2, an overlooked component of interstellar ices." The Astrophysical Journal Letters 808 (2): L40 [Full Text (Link)] [10.1088/2041-8205/808/2/L40]

    Smith, K. E., M. P. Callahan, P. A. Gerakines, J. P. Dworkin, and C. H. House. 2014. "Investigation of pyridine carboxylic acids in CM2 carbonaceous chondrites: Potential precursor molecules for ancient coenzymes." Geochimica et Cosmochimica Acta 136 1-12 [Full Text (Link)] [10.1016/j.gca.2014.04.001]

    Hudson, R. L., P. A. Gerakines, and M. H. Moore. 2014. "Infrared Spectra and Optical Constants of Astronomical Ices: II. Ethane and Ethylene." Icarus 243 147-148 [10.1016/j.icarus.2014.09.001]

    Gerakines, P. A., and R. L. Hudson. 2013. "Glycine's Radiolytic Destruction in Ices: First in situ Laboratory Measurements for Mars." Astrobiology 13 647-655 [10.1089/ast.2012.0943]

    Callahan, M. P., P. A. Gerakines, M. G. Martin, Z. Peeters, and R. L. Hudson. 2013. "Irradiated benzene ice provides clues to meteoritic organic chemistry." Icarus 226 (2): 1201-1209 [Full Text (Link)] [10.1016/j.icarus.2013.07.033]

    Gerakines, P. A., R. L. Hudson, M. H. Moore, and J.-L. Bell. 2012. "In-situ Measurements of the Radiation Stability of Amino Acids at 15 - 140 K." Icarus 220 647-659 [10.1016/j.icarus.2012.06.001]

    Richey, C. R., and P. A. Gerakines. 2012. "Near-infrared band strengths of molecules diluted in N2 and H2O ice mixtures relevant to interstellar and planetary ices." The Astrophysical Journal 759 74-86 [10.1088/0004-637X/759/1/74]

    Cook, A. M., D. C. Whittet, S. S. Shenoy, et al. P. A. Gerakines, D. W. White, and J. E. Chiar. 2011. "The Thermal Evolution of Ices in the Environments of Newly Formed Stars: The CO2 Diagnostic." The Astrophysical Journal 730 (2): 124-138 [10.1088/0004-637X/730/2/124]

    Agresti, D. G., and P. A. Gerakines. 2009. "Simultaneous Fitting of Mars Moessbauer Data." Hyperfine Interactions 188 113-120 [10.1007/s10751-008-9896-1]

    Whittet, D. C., A. M. Cook, S. S. Shenoy, et al. J. E. Chiar, Y. J. Pendleton, and P. A. Gerakines. 2009. "The Nature of Carbon Dioxide Bearing Ices in Quiescent Molecular Clouds." The Astrophysical Journal 695 94-100 [10.1088/0004-637X/695/1/94]

    White, D., P. A. Gerakines, D. Whittet, and A. Cook. 2009. "Laboratory Spectra of the CO2 Bending-Mode Feature in Interstellar Ice Analogs Subject to Thermal Processing." Astrophysical Journal Supplement Series 180 182-191 [Full Text (Link)] [10.1088/0067-0049/180/1/182]

    Sonnentrucker, P., D. A. Neufeld, P. A. Gerakines, et al. E. A. Bergin, G. J. Melnick, W. J. Forrest, J. L. Pipher, and D. C. Whittet. 2008. "Fully Sampled Maps of Ices and Silicates in Front of Cepheus A East with Spitzer." The Astrophysical Journal 672 361-370

    Whittet, D. C., S. S. Shenoy, E. A. Bergin, et al. J. E. Chiar, P. A. Gerakines, E. L. Gibb, G. J. Melnick, and D. A. Neufeld. 2007. "The abundance of carbon dioxide ice in the quiescent intracloud medium." The Astrophysical Journal 655 332-341

    Abbas, M. M., D. Tankosic, P. D. Craven, et al. J. F. Spann, A. LeClair, E. A. West, J. C. Weingartner, A. G. Tielens, J. A. Nuth, R. P. Camata, and P. A. Gerakines. 2006. "Photoelectric Emission Measurements on the Analogs of Individual Cosmic Dust Grains." The Astrophysical Journal 645

    Gerakines, P. A., J. J. Bray, A. Davis, and C. R. Richey. 2005. "The Strengths of Near-Infrared Absorption Features Relevant to Interstellar and Planetary ices." The Astrophysical Journal 620 1140-1150

    Bergin, E. A., G. J. Melnick, P. A. Gerakines, D. A. Neufeld, and D. C. Whittet. 2005. "Spitzer Observations of CO2 Ice Towards Field Stars in the Taurus Molecular Cloud." The Astrophysical Journal 627 L33-L36

    Gerakines, P. A., M. H. Moore, and R. L. Hudson. 2004. "Ultraviolet Photolysis and Proton Irradiation of Astrophysical Ice Analogs Containing Hydrogen Cyanide." Icarus 170 202-213

    Gerakines, P. A., M. H. Moore, and R. L. Hudson. 2001. "Energetic Processing of Laboratory Ice Analogs: UV Photolysis vs. Ion Bombardment." JGR-Planets 106 33381-33386

    Whittet, D. C., P. A. Gerakines, J. H. Hough, and S. S. Shenoy. 2001. "Interstellar Extinction and Polarization in the Taurus Dark Clouds: The Optical Properties of Dust near the Diffuse/Dense Cloud Interface." The Astrophysical Journal 547 872-884

    Moore, M. H., R. L. Hudson, and P. A. Gerakines. 2001. "Mid- and Far-Infrared Spectroscopic Studies of the Influence of Temperature, Ultraviolet Photolysis, and Ion Irradiation on Cosmic-Type Ices." Spectrochimica Acta A 57 843-858

    Hudson, R. L., M. H. Moore, and P. A. Gerakines. 2001. "The Formation of Cyanate Ion (OCN-) in Interstellar Ice Analogs." The Astrophysical Journal 550 1140-1150

    Nummelin, A., D. C. Whittet, E. L. Gibb, P. A. Gerakines, and J. E. Chiar. 2001. "Solid Carbon Dioxide in Regions of Low-Mass Star Formation." The Astrophysical Journal 558 185-193

    Wdowiak, T. J., P. A. Gerakines, D. G. Agresti, and S. J. Clemett. 2001. "Technology Considerations Relevant to an Exobiology Surface-Science Approach for Europa." Astrobiology 1 467-476

    Gerakines, P. A., and M. H. Moore. 2001. "Carbon Suboxide in Astrophysical Ice Analogs." Icarus 154 372-380

    Boogert, A. C., P. Ehrenfreund, P. A. Gerakines, et al. A. G. Tielens, D. C. Whittet, W. A. Schutte, E. F. van Dishoeck, T. de Graauw, L. Decin, and T. Prusti. 2000. "ISO-SWS Observations of Interstellar Solid 13CO2: Heated Ice and the Galactic 12C/13C Abundance Ratio." Astronomy & Astrophysics 353 349-362

    Gerakines, P. A., M. H. Moore, and R. L. Hudson. 2000. "Carbonic Acid Production in H2O:CO2 ices UV Photolysis vs Proton Bombardment." Astronomy & Astrophysics 357 793-800

    Gibb, E. L., D. C. Whittet, W. A. Schutte, et al. A. C. Boogert, J. E. Chiar, P. Ehrenfreund, P. A. Gerakines, J. V. Keane, A. G. Tielens, E. F. van Dishoeck, and O. Kerkhof. 2000. "An Inventory of Interstellar Ices toward the Embedded Protostar W33A." The Astrophysical Journal 536 347-356

    Schutte, W. A., A. C. Boogert, A. G. Tielens, et al. D. C. Whittet, P. A. Gerakines, J. E. Chiar, P. Ehrenfreund, J. M. Greenberg, E. F. van Dishoeck, and T. de Graauw. 1999. "Weak Ice Absorption Features in the Spectrum of the Obscured Young Stellar Object W33 A." Astronomy & Astrophysics 343 966-976

    Vandenbussche, B., P. Enhrenfreund, A. C. Boogert, et al. E. F. van Dishoeck, W. A. Schutte, P. A. Gerakines, J. E. Chiar, A. G. Tielens, J. V. Keane, D. C. Whittet, M. Breitfellner, and M. Burgdorf. 1999. "Constraints on the Abundance of Solid O2 in Dense Clouds from ISO-SWS and Ground-Based Observations ." Astronomy & Astrophysics 346 L57-L60

    Gerakines, P. A., D. C. Whittet, P. Ehrenfreund, et al. A. C. Boogert, A. G. Tielens, W. A. Schutte, J. E. Chiar, E. F. van Dishoeck, T. Prusti, F. P. Helmich, and T. de Graauw. 1999. "Observations of Solid Carbon Dioxide in Molecular Clouds with the Infrared Space Observatory." The Astrophysical Journal 522 357-377

    Ehrenfreund, P., O. Kerkhof, W. A. Schutte, et al. A. C. Boogert, P. A. Gerakines, E. Dartois, L. dHendecourt, A. G. Tielens, E. F. van Dishoeck, and D. C. Whittet. 1999. "Laboratory Studies of Thermally Processed H2O-CH3OH-CO2 Ice Mixtures and their Astrophysical Implications." Astronomy & Astrophysics 350 240?253

    Chiar, J. E., P. A. Gerakines, D. C. Whittet, et al. Y. J. Pendleton, A. G. Tielens, A. J. Adamson, and A. C. Boogert. 1998. "Processing of Icy Mantles in Protostellar Envelopes." The Astrophysical Journal 498 716-727

    Whittet, D. C., P. A. Gerakines, A. G. Tielens, et al. A. J. Adamson, A. C. Boogert, J. E. Chiar, T. de Graauw, P. Ehrenfreund, T. Prusti, W. A. Schutte, B. Vandenbussche, and E. F. van Dishoeck. 1998. "Detection of Abundant CO2 Ice in the Quiescent Dark Cloud Medium toward Elias 16." The Astrophysical Journal 498 L159-L163

    Whittet, D. C., T. Prusti, G. A. Franco, et al. P. A. Gerakines, D. Kilkenny, K. A. Larson, and P. R. Wesselius. 1997. "On the Distance to the Chamaeleon I and II Associations." Astronomy & Astrophysics 327 1194-1205

    Ehrenfreund, P., A. C. Boogert, P. A. Gerakines, A. G. Tielens, and E. F. van Dishoeck. 1997. "Infrared Spectroscopy of Interstellar Apolar Ice Analogs." Astronomy & Astrophysics 328 649-669

    Whittet, D. C., A. C. Boogert, P. A. Gerakines, et al. W. A. Schutte, A. G. Tielens, T. de Graauw, T. Prusti, E. F. van Dishoeck, P. R. Wesselius, and C. M. Wright. 1997. "Infrared Spectroscopy of Dust in the Diffuse Interstellar Medium toward Cygnus OB2 No 12." The Astrophysical Journal 490 729-734

    Schutte, W. A., P. A. Gerakines, T. R. Geballe, E. F. van Dishoeck, and J. M. Greenberg. 1996. "Discovery of Solid Formaldehyde toward the Protostar GL 2136: Observations and Laboratory Simulation." Astronomy & Astrophysics 309 633-647

    Ehrenfreund, P., P. A. Gerakines, W. A. Schutte, M. C. van Hemert, and E. F. van Dsihoeck. 1996. "Infrared Properties of Isolated Water Ice." Astronomy & Astrophysics 312 263-274

    Gerakines, P. A., W. A. Schutte, and P. Ehrenfreund. 1996. "Ultraviolet Processing of Interstellar Ice Analogs: Pure Ices." Astronomy & Astrophysics 312 289-305

    Ehrenfreund, P., A. C. Boogert, P. A. Gerakines, et al. D. J. Jansen, W. A. Schutte, A. G. Tielens, and E. F. van Dishoeck. 1996. "A Laboratory Database of Solid CO and CO2 for ISO." Astronomy & Astrophysics 315 L341-L344

    de Graauw, T., D. C. Whittet, P. A. Gerakines, et al. O. H. Bauer, D. A. Beintema, A. C. Boogert, D. R. Boxhoorn, J. E. Chiar, P. Ehrenfreund, H. Feuchtgruber, F. P. Helmich, A. M. Heras, R. Huygen, D. J. Kester, D. Kunze, P. W. Morris, T. Prusti, P. R. Roelfsema, A. Salama, S. G. Schaeidt, W. A. Schutte, H. W. Spoon, A. G. Tielens, E. A. Valentijn, B. Vandenbussche, E. F. van Dishoeck, P. R. Wesselius, E. Wieprecht, and C. M. Wright. 1996. "SWS Observations of Solid CO2 in Molecular Clouds." Astronomy & Astrophysics 315 L345-L348

    van Dishoeck, E. F., F. P. Helmich, T. de Graauw, et al. J. H. Black, A. C. Boogert, P. Ehrenfreund, P. A. Gerakines, J. H. Lacy, T. J. Millar, W. A. Schutte, A. G. Tielens, D. C. Whittet, D. R. Boxhoorn, D. J. Kester, K. Leech, P. R. Roelfsema, A. Salama, and B. Vandenhussche. 1996. "A Search for Interstellar Gas-phase CO2 - Gas:Solid-State Abundance Ratios." Astronomy & Astrophysics 315 L349-L352

    Whittet, D. C., W. A. Schutte, A. G. Tielens, et al. A. C. Boogert, T. de Graauw, P. Ehrenfreund, P. A. Gerakines, F. P. Helmich, T. Prusti, and E. F. van Dishoeck. 1996. "An ISO-SWS View of Interstellar Ices: First Results." Astronomy & Astrophysics 315 L357-L360

    Schutte, W. A., and P. A. Gerakines. 1995. "Recent Results from the Leiden Observatory Laboratory: (a) Band Strengths in Mixed Ices; (b) UV Photolysis of Solid Methanol." Planetary & Space Science 43 1253-1256

    Gerakines, P. A., and D. C. Whittet. 1995. "A Review of Interstellar Polarization Properties and Recent Measurements toward the Chamaeleon I and Taurus Dark Clouds." Planetary & Space Science 43 1325-1328

    Gerakines, P. A., W. A. Schutte, J. M. Greenberg, and E. F. van Dishoeck. 1995. "The Infrared Band Strengths of H2O, CO, and CO2 in Laboratory Simulations of Astrophysical Ice Mixtures." Astronomy & Astrophysics 296 810-818

    Gerakines, P. A., D. C. Whittet, and A. Lazarian. 1995. "Grain Alignment in the Taurus Dark Cloud." The Astrophysical Journal 455 L171-L175

    Greenberg, J. M., A. Li, C. X. Mendoza-Gomez, et al. W. A. Schutte, P. A. Gerakines, and M. de Groot. 1995. "Approaching the Interstellar Grain Organic Refractory Component." The Astrophysical Journal 455 L177-L180

    Whittet, D. C., P. A. Gerakines, A. L. Carkner, et al. J. H. Hough, P. G. Martin, T. Prusti, and D. Kilkenny. 1994. "A Study of the Chamaeleon-I Dark Cloud and T-Association - Part VI - Interstellar Polarization, Grain Alignment, and Magnetic Field." Monthly Notices of the Royal Astronomical Society 268 1-12

                                                                                                                                                                                            
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