Solar System Exploration Division

Geronimo Villanueva (he/his)

(Associate Director for Strategic Science)

Geronimo Villanueva (he/his)'s Contact Card & Information.
Email: geronimo.l.villanueva@nasa.gov
Phone: 301.286.1528
Org Code: 690
Address:
NASA/GSFC
 Mail Code 690
 Greenbelt, MD 20771
Employer:
NASA

Brief Bio

Dr. Geronimo Villanueva is the Associate Director for Strategic Science of the Solar System Exploration Division at NASA Goddard Space Flight Center, and specializes in the search for astrobiology-relevant species on Mars, Venus, Ocean Worlds (Europa, Enceladus), primordial bodies (comets) and in distant exoplanets. He is the Principal Investigator (PI) of the Planetary Spectrum Generator (PSG), Co-lead Scientist of the Comet Interceptor MIRMIS instrument, Co-Investigator of the ExoMars/TGO mission, and leader for Mars and Ocean Worlds studies (GTO) for the James Webb Space Telescope (JWST). In recognition to his work on small bodies, the International Astronomical Union (IAU) named minor planet '9724' after Dr. Villanueva, in 2015 the American Astronomical Society (AAS) honored him with the Urey Prize (young planetary scientist of the year), and in 2023 he was awarded the Lindsay Memorial Award in Space Science by NASA, among other honors and awards.


Since completing his Ph.D. studies at the Max-Planck-Institute for Solar-System Research in Germany in 2004, Dr. Villanueva has participated in many projects at three space agencies, NASA, ESA (European Space Agency) and DLR (German Aerospace Agency), with a broad range of research experience in planetary, exploration and Space sciences. He is a strong advocate for Space Exploration and Astronomy, participating in numerous public outreach activities promoting science to underrepresented communities and in developing regions.


For more information refer to: http://astrobiology.gsfc.nasa.gov/Villanueva/

Current Projects

Mission and Research Activities

Solar System

Principal Investigator (PI) of the Planetary Spectrum Generator (PSG), a comprehensive and highly advanced planetary simulation online tool, which is now one of the most used scientific tools in the world, receiving up to 1 million hits per month worldwide. PSG is being used to perform exoplanet research, to simulate solar system objects (e.g., comets), to support missions (e.g., ExoMars, JWST), to develop new instrumentation (e.g., PICASSO, MatISSE) and missions (e.g., Discovery, New Frontiers, LUVOIR, OST), to do Earth sciences, and even Solar physics. 

Project Scientist (PS) of the Chimera Discovery mission concept, a mission to be managed by NASA-GSFC and with international participation. 

Co-lead Scientist and Co-Investigator (Co-I) of the ESA/F-Class Comet Interceptor mission, primarily supporting the development of the Multispectral InfraRed Molecular and Ices Sensor (MIRMIS) instrument for the ESA/F-Class Comet Interceptor mission concept (now in phase 2).

Co-Investigator (Co-I) of the ExoMars/NOMAD mission (ESA/Roscomos/NASA). Some results from our team include: a) we developed a realistic optimal estimation package for PSG and we are leading several science cases for the mission b) we developed a cluster retrieval computational center for the ExoMars mission at GSFC that employs hundreds of computational cores; c) we performed a detailed characterization of the NOMAD instrument and developed of a novel calibration methodology.

Lead of two JWST Guaranteed-Time-Observation programs, Mars and Icy Worlds (Europa/Enceladus) as part of Hammel’s solar system team, and participated in several Early-Release-Science and GO programs for comets, Europa and proto-planetary disks.

Principal Investigator (PI) of an astrochemical ROSES Emerging Worlds project. Some results include: a) Creation of an extensive archive of cometary IR data (1989-2018); b) High-quality Keck, NASA-IRTF and VLT data of 60 comets identified and organized; c) Extraction of abundances employing the latest models and retrieval methods for water, dozens of organics and several cosmogonic indicators (e.g., OPR, D/H); d) Development of a quantum-band model of the deuterated ethane.

Principal Investigator (PI) of a ROSES Exoplanets Research (XRP) project. Some results include: a) Development of a non-LTE radiative transfer module for PSG; b) Development of a modern high-temperature molecular database applicable to low and high resolution spectroscopy; c) Development radiative transfer and sensitivity models for a variety of exoplanetary observational modes (e.g., coronagraphy, transit and cross-correlation).

Principal Investigator (PI) and Co-Investigator (Co-I) in several astronomical studies performed with ground-based observatories: a) Mars observations with ALMA, Keck and NASA-IRTF; b) Detection of water in Europa with Keck; c) High-resolution spectroscopy of comets with ground-based observatories (e.g., Keck, IRTF).

Technology Development

Technology & Missions

  • Co-chair of the Solar System group for the LUVOIR (Large-UV-Optical-Infrared) NASA Decadal observatory (2016-2020).
  • Group co-lead: “Laser Measurements of Atmospheric trace gases” Science Task Group (STG).
  • Observations lead, “Ocean Worlds Science, Exploration and Analogs (OSEAN)”, Science Task Group (STG).
  • Submillimeter Planetary instrumentation (Radical Innovation Project, PI: Gordon Chin), supporting the instrument design and science development.
  • SELFI (Enceladus MatISSE funded project, PI: Gordon), supporting the instrument design and detectability analysis.
  • PROVE (Cometary CubeSat PSDS3 funded project and SIMPLEX-2 concept, PI: Hewagama), developing the science case.
  • SSOLVE (Lunar MatISSE concept, PI: Livengood), supporting the instrument design and detectability analysis.
  • MLLS (Mars Laser Limb Sounding, IRAD funded and PICASSO concept, PI: Riris), supporting the instrument design and detectability analysis.
  • INFR (Ice-giants Net Flux Radiometer, PICASSO funded, PI: Aslam), supporting the instrument design and detectability analysis.
  • MIRECLE (Mid InfraRed Exoplanet CLimate Explorer, MIDEX concept: PI: Staguhn), supporting the mission design and detectability analysis.
  • Co-Chair of the Solar System Group for LUVOIR, and member the Science Support Advisory team, leading a team of planetary sciences who prepared the solar system science cases and DRMs for this frontier concept observatory
  • Lead of the planetary simulation tool for the Origins Space Telescope (OST) concept, and assisted in the development of the solar system science cases and DRMs for this concept observatory.

Positions/Employment

Associate Director, Strategic Science

Solar System Exploration Division - NASA Goddard Space Flight Center

2023 - Present

Planetary Scientist and Lead of PSG

NASA Goddard Space Flight Center - Greenbelt, MD

2016 - 2023

Research Assistant Professor

CUA at NASA Goddard Space Flight Center - Greenbelt, MD

2008 - 2016

Post-Doctoral Research Assistant

Max-Planck-Institut für Sonnensytemforschung - Germany

2004 - 2005

Ph.D. student

Max-Planck-Institut für Sonnensytemforschung and Freiburg University - Germany

2001 - 2004

Founder and Director

Tecnoware Medical Software - Mendoza, Argentina

1998 - 2001

Director of Systems Development

Logic Express Software - Mendoza, Argentina

1997 - 1998

Statistical Analyst and Programmer

Gallup International - Mendoza, Argentina

1994 - 1996

Education

  • Doctorate (Ph.D.), "The High Resolution Spectrometer for SOFIA-GREAT: Instrumentation, Atmospheric Modeling and Observations". Magna Cum Laude, November 2004, Germany. Research performed at and in collaboration with:
    • Albert Ludwig University of Freiburg, Faculty for Applied Sciences, Institut für Mikrosystemtechnik and Kiepenheuer-Institut für Sonnenphysik.
    • Max-Planck-Institut für Sonnensystemforschung (MPS), Lindau, Germany.
    • Deutschen Zentrum für Luft- und Raumfahrt (DLR), German Aerospace Agency.
    • National Aeronautics and Space Administration (NASA).
    • European Space Agency (ESA).
  • Master's Certification (Diplomarbeit Anerkennung), Clausthal Technical University, February 2003, Germany
  • M.S.T.E Atmospheric Radiometry, Universidad Mendoza, Institute for Environmental Studies, 2001, Argentina

Research Interests

Research Experience

Solar System: Astrobiology

  • Broad range of expertise in spectroscopic studies of comets, planets (e.g., Mars, Earth, Venus), exoplanets and protoplanetary disks employing powerful observatories: infrared (Keck, VLT, NASA-IRTF, JWST, Gemini South), radio (ALMA, Herschel, APEX, GBT, HHSMT, CSO, JCMT, KP12m) and X-rays/UV (NASA Swift).
  • Lead investigator of the discovery of a carbon source on Europa (Villanueva+2023, Science) and the extraordinary characterization of Enceladus plume with JWST (Villanueva+2023, Nature Astronomy).
  • Lead investigator of the first global mapping of water D/H on Mars (Villanueva+2022, Science Advances, Villanueva+2015, Science), establishing the history of water on Mars.
  • Lead author of the one of the most comprehensive search for organics in the Martian atmosphere (Villanueva+2013, Icarus).
  • Lead author of the first astronomical measurement of water D/H of a periodic comet (Villanueva+2009).
  • Lead developer of non-LTE radiative transfer models and quantum molecular models for C2H6, CH3OH, H2O, HDO, HCN, NH3, HNC, HC3N resulting in billions of spectral lines suitable for cometary, planetary and astrophysical sciences, including exoplanets.
  • Discoverer of multiple isotopic carbon dioxide bands on Mars at infrared wavelengths, impacting previous searches for trace species on Mars and further constraining greenhouse energy budgets (Villanueva+2008, Icarus and JQSRT).
  • Lead developer of a unique set of data processing techniques for echelle spectrographs that have allowed the investigation of planetary atmospheres (comets, Mars, exoplanets) with unprecedented sensitivity (https://github.com/nasapsg).
  • Expert on Microwave/Sub-mm RF development (microstrip/stripline, TEM modeling, detectors), with participation on the development of the Rosetta-MIRO and Herschel-HIFI instruments.
  • Lead designer and developer of the highest resolution spectrometer (GREAT-CTS) onboard SOFIA (Villanueva 2004, Villanueva+2004/2005).
  • Developer of a full non-linear dynamical General Circulation Model (GCM) for Mars (Villanueva 2004, Hartogh+2005).
  • Supervision and training and many undergrad, Ph.D. students and post-doctoral fellows.

Professional Service

  • Co-Investigator of Goddard's Astrobiology Institute (2005-present).
  • Member of the Hispanic Advisory Committee for Employees (HACE) at NASA Goddard Space Flight Center (2010-present).
  • Member of the Science Steering Commitee (SSC) for the Keck observatory (2017-2022).
  • Member of the Management Operations Working Group (MOWG) for Keck and NASA-IRTF telescopes (2011-2017).
  • Member of the Atacama Large Millimeter Array (ALMA) Time Allocation Committee (2014-2016).
  • Scientific adviser for planetary sciences to ESO for E-ELT and to NASA-IRTF for iSHELL.
  • Official Reviewer for the Mars-Express mission, Planetary Fourier Spectrometer (MEX-PFS) Archive. European Space Agency (ESA) (2008).
  • Organizer (SOC) of several international conferences (e.g., Planets2020, Goddard CubeSats 2018, Cosmochemistry conference in Sweden 2014, Astrobiology conference in Chile - Astrobio 2013).
  • Reviewer of scientific articles submitted to Science, Nature, Icarus, Astrophysical Journal, Space Science Reviews Journal, Advances in Space Research, Journal of Geophysical Research, Advances in Geosciences, and PASP.
  • Reviewer of funding proposals submitted to NASA's Planetary Atmospheres, NASA's Astrophysics Data Analysis Program, NASA's Mars Fundamental Research, NASA's Outer Planets Program, NASA's Origins of Solar Systems Programs, and to the Spanish Research and Innovation program (I+D+i).
  • Member of the American Astronomical Society (Division for Planetary Sciences), the European Geosciences Union, the Institute of Electrical and Electronics Engineering (IEEE), and the Sigma Xi Honor Research Society.

Awards

  • Awardee of the 2023 John C. Lindsay Memorial Award for Space Science together with Michael Smith, in recognition for highly successful spectral modeling and interpretation of solar system bodies and atmospheres.
  • Finalist and Goddard's nominee for NASA's Inventions and Contributions Board (ICB) Software of the Year (SOY) award (PSG team, 2022).
  • Awardee of the 2015 Harold C. Urey Prize for outstanding achievement in planetary research, the highest honor for a young planetary scientist from the American Astronomical Society.
  • The International Astronomical Union (IAU) named minor planet 1981EW17 "(9724) Villanueva", in honor to Dr. Villanueva's research contributions in the area of high-resolution molecular spectroscopy of planetary and cometary atmospheres.
  • Awardee of the NASA Goddard Exceptional Award in Science, LUVOIR SSAT (2020).
  • Awardee of the NASA Goddard Exceptional Award, Artemis Live Shot Team (2020).
  • Awardee of the NASA Group Achievement Award, Astrophysics Large Mission Team (2019).
  • Awardee of the NASA Solar System Exploration Division Peer Award (2019 and 2010).
  • Awardee of the NASA Goddard Exceptional Award in Science, Mars ground-based Team (2009).
  • Awardee of the National Research Council (NRC) Fellowship, American National Academy of Sciences (NAS 2005).
  • Lead investigator of one of the most exciting works in Nature Communications in 2023, and lead investigator of one of the most popular articles in Planetary Sciences of 2013 (Villanueva+2023) as ranked by Elsevier.
  • Article of the day (NASA Astrophysics Data System, Oct/12/2011), lead author and co-author of three Astronomy Pictures of the Day (Dec/22/2014, Jan/19/2009, Feb/21/2009).

Selected Public Outreach

Education and Public Outreach

2005 - Present

  • Deployment to the US-Mexico border (2022): Assisting with the humanitarian crisis on the US Southern Border by working at Donna Immigration Detention Center during the August/2022 immigration crisis.
  • Invited keynote Speaker for the NASA Goddard Hispanic Community (HACE) annual event (2023, 2016).
  • TEDx "Estamos Solos" (2017): Outreach talk about the astronomical search for life to a broad audiance of 10,000 spectators as part of the "TEDx Rio de la Plata" annual event.
  • BBC New Horizons Documentary Series, "Oceans of the Solar System" (2015). The film production included filming in the Atacama desert and a detailed interview about oceans on Mars.
  • Science lecturer for Shakira's foundation 'Pies Descalzos' with the goal of promoting science and technology to impoverished children in Latin America and in Africa.
  • Science Ambassador: Appointed and granted funds by the US Department of State to promote astronomy and physics in under-developed regions of Chile (2013).
  • Organizing Scientist of the MAS+ project "Reducing the Digital Divide in Argentina". This project, sponsored by Microsoft, provides training and access to the newest technologies to young students of public schools and universities.
  • Discovery/Science Channel, "New Life on Mars?" (Jan-2009). The Science Channel prepared a documentary presenting the discovery of methane on Mars, and Dr. Villanueva was invited to present the results and comment on the implications of the discovery to future exploration missions to Mars.
  • Spokesman of the NASA Swift mission (optical, UV, X-ray) for "100 hours of Astronomy" (Apr-2009), a live 24-hour webcast.
  • NASA TV, "Is Mars an Active Planet?" Science Update (Jan-2009). This televised report presented the methane results on Mars and was covered by multiple national and international media stations.
  • Mentoring and supervision of a broad team of scientists and students.
  • Numerous refereed publications, proceedings/conference presentations, and contributions to public media (press, radio and TV).

Selected Publications

Refereed

2024. "Detectability Simulations of a Near-infrared Surface Biosignature on Proxima Centauri b with Future Space Observatories." The Planetary Science Journal 5 (10): 228 [10.3847/psj/ad769d] [Journal Article/Letter]

2024. "The CUISINES Framework for Conducting Exoplanet Model Intercomparison Projects, Version 1.0." The Planetary Science Journal 5 (8): 175 [10.3847/psj/ad5830] [Journal Article/Letter]

2024. "JWST Reveals CO Ice, Concentrated CO2 Deposits, and Evidence for Carbonates Potentially Sourced from Ariel’s Interior." The Astrophysical Journal Letters 970 (2): L29 [10.3847/2041-8213/ad566a] [Journal Article/Letter]

2024. "Accretion of Meteoric Organic Matter at the Surface of Mars and Potential Production of Methane by Ultraviolet Radiation." The Planetary Science Journal 5 (7): 160 [https://dx.doi.org/10.3847/PSJ/ad54c9] [Journal Article/Letter]

2024. "Revealing Callisto’s Carbon-rich Surface and CO2 Atmosphere with JWST." The Planetary Science Journal 5 (3): 60 [10.3847/psj/ad23e6] [Journal Article/Letter]

2024. "Modelling for Comet Interceptor's Modular InfraRed Molecules and Ices Sensor." LPI Contributions 3040 1386 [Proceedings]

2024. "The Comet Interceptor Mission." Space Science Reviews 220 (1): 9 [10.1007/s11214-023-01035-0] [Journal Article/Letter]

2024. "Improved Design of an Advanced Ice Giants Net Flux Radiometer." Space Science Reviews 220 (1): 5 [10.1007/s11214-023-01038-x] [Journal Article/Letter]

2024. "The Modular Infrared Molecules And Ices Sensor (MIRMIS): An Instrument Visiting A Long-Period Comet." Abstract from 21st Annual Meeting AOGS 2024, Pyeongchang, Korea, Republic of 1 [Proceedings]

2023. "Author's Reply to Comment by Greaves et al. on “Phosphine in the Venusian Atmosphere: A Strict Upper Limit From SOFIA GREAT Observations”." Geophysical Research Letters 50 (23): [10.1029/2023gl106136] [Journal Article/Letter]

2023. "The Return of the Rosetta Target: Keck Near-infrared Observations of Comet 67P/Churyumov–Gerasimenko in 2021." The Astronomical Journal 166 (6): 233 [10.3847/1538-3881/acee59] [Journal Article/Letter]

2023. "Molecular Outgassing in Centaur 29P/Schwassmann–Wachmann 1 during Its Exceptional 2021 Outburst: Coordinated Multiwavelength Observations Using nFLASH at APEX and iSHELL at the NASA-IRTF." The Planetary Science Journal 4 (9): 172 [10.3847/psj/ace1e9] [Journal Article/Letter]

2023. "Bayesian Analysis for Remote Biosignature Identification on exoEarths (BARBIE). I. Using Grid-based Nested Sampling in Coronagraphy Observation Simulations for H2O." The Astronomical Journal 166 (3): 129 [10.3847/1538-3881/acebc3] [Journal Article/Letter]

2023. "Grid-based Atmospheric Retrievals for Reflected-light Spectra of Exoplanets Using PSGnest." The Astronomical Journal 166 (3): 86 [10.3847/1538-3881/ace43b] [Journal Article/Letter]

2023. "Gas Sources from the Coma and Nucleus of Comet 46P/Wirtanen Observed Using ALMA." The Astrophysical Journal 953 (1): 59 [10.3847/1538-4357/ace0bc] [Journal Article/Letter]

2023. "Martian Meteoric Mg + : Atmospheric Distribution and Variability From MAVEN/IUVS." Journal of Geophysical Research: Planets 128 (1): [10.1029/2022je007315] [Journal Article/Letter]

2022. "The TRAPPIST-1 Habitable Atmosphere Intercomparison (THAI). III. Simulated Observables—the Return of the Spectrum." The Planetary Science Journal 3 (9): 213 [10.3847/psj/ac6cf1] [Journal Article/Letter]

2022. "Simulated design trades for a visible-wavelength integral field spectrograph operating behind a space coronagraph." Space Telescopes and Instrumentation 2022: Optical, Infrared, and Millimeter Wave [10.1117/12.2630443] [Proceedings]

2022. "Explaining NOMAD D/H Observations by Cloud‐induced Fractionation of Water Vapor on Mars." Journal of Geophysical Research: Planets [10.1029/2021je007079] [Journal Article/Letter]

2022. "EarthShine: Observing our world as an exoplanet from the surface of the Moon." Journal of Astronomical Telescopes, Instruments, and Systems 8 (01): 014003 [10.1117/1.jatis.8.1.014003] [Journal Article/Letter]

2021. "MiniCarb: a passive, occultation-viewing, 6U CubeSat for observations of CO2, CH4, and H2O." Measurement Science and Technology 33 (1): 015902 [10.1088/1361-6501/ac3679] [Journal Article/Letter]

2021. "First Detection and Thermal Characterization of Terminator CO 2 Ice Clouds With ExoMars/NOMAD." Geophysical Research Letters 48 (22): [10.1029/2021gl095895] [Journal Article/Letter]

2021. "A Global and Seasonal Perspective of Martian Water Vapor From ExoMars/NOMAD." Journal of Geophysical Research: Planets 126 (11): [10.1029/2021je006878] [Journal Article/Letter]

2021. "The Extraordinary Passage of Comet C/2020 F3 NEOWISE: Evidence for Heterogeneous Chemical Inventory in Its Nucleus." The Astronomical Journal 162 (5): 178 [10.3847/1538-3881/ac179c] [Journal Article/Letter]

2021. "Martian water loss to space enhanced by regional dust storms." Nature Astronomy [10.1038/s41550-021-01425-w] [Journal Article/Letter]

2021. "Investigation of the Origins of Comets as Revealed through Infrared High-resolution Spectroscopy I. Molecular Abundances." The Astronomical Journal 162 (2): 74 [10.3847/1538-3881/abfdb7] [Journal Article/Letter]

2021. "No evidence of phosphine in the atmosphere of Venus from independent analyses." Nature Astronomy 5 (7): 631-635 [10.1038/s41550-021-01422-z] [Journal Article/Letter]

2021. "Simulating Reflected Light Exoplanet Spectra of the Promising Direct Imaging Target, υ Andromedae d, with a New, Fast Sampling Method Using the Planetary Spectrum Generator." The Astronomical Journal 162 (1): 30 [10.3847/1538-3881/abf657] [Journal Article/Letter]

2021. "Probing the Atmospheric Cl Isotopic Ratio on Mars: Implications for Planetary Evolution and Atmospheric Chemistry." Geophysical Research Letters 48 (9): [10.1029/2021gl092650] [Journal Article/Letter]

2021. "Absorption in exoplanet atmospheres: Combining experimental and theoretical databases to facilitate calculations of the molecular opacities of water." Journal of Quantitative Spectroscopy and Radiative Transfer 270 107708 [10.1016/j.jqsrt.2021.107708] [Journal Article/Letter]

2021. "Comprehensive investigation of Mars methane and organics with ExoMars/NOMAD." Icarus 357 114266 [10.1016/j.icarus.2020.114266] [Journal Article/Letter]

2021. "Nitrogen Dioxide Pollution as a Signature of Extraterrestrial Technology." The Astrophysical Journal 908 (2): 164 [10.3847/1538-4357/abd7f7] [Journal Article/Letter]

2020. "Modelling the expected observations of the Advanced Ice Giants Net Flux Radiometer (IG-NFR) instrument concept, under study for future entry probe missions to Uranus or Neptune." EPSC Abstracts EPSC2020-306 [10.5194/epsc2020-306] [Proceedings]

2020. "The First Habitable-zone Earth-sized Planet from TESS. I. Validation of the TOI-700 System." The Astronomical Journal 160 (3): 116 [10.3847/1538-3881/aba4b2] [Journal Article/Letter]

2020. "The First Habitable Zone Earth-sized Planet from TESS. III: Climate States and Characterization Prospects for TOI-700 d." The Astronomical Journal 160 (118): 19pp. [10.3847/1538-3881/aba4b4] [Journal Article/Letter]

2020. "Detectability of Molecular Signatures on TRAPPIST-1e through Transmission Spectroscopy Simulated for Future Space-based Observatories." The Astrophysical Journal 898 (2): L33 [10.3847/2041-8213/aba4a1] [Journal Article/Letter]

2020. "A new model of monodeuterated ethane (C2H5D) spectrum: Enabling sensitive constraints on the D/H in ethane emission in comets." Journal of Quantitative Spectroscopy and Radiative Transfer 255 107225 [10.1016/j.jqsrt.2020.107225] [Journal Article/Letter]

2020. "Strong Variability of Martian Water Ice Clouds During Dust Storms Revealed From ExoMars Trace Gas Orbiter/NOMAD." Journal of Geophysical Research: Planets 125 (4): [10.1029/2019je006250] [Journal Article/Letter]

2020. "Dim Prospects for Transmission Spectra of Ocean Earths around M Stars." The Astrophysical Journal 891 (1): 58 [10.3847/1538-4357/ab72f9] [Journal Article/Letter]

2020. "Advanced Net Flux Radiometer for the Ice Giants." Space Science Reviews 216 (1): 11 [10.1007/s11214-019-0630-x] [Journal Article/Letter]

2020. "Sensitive probing of exoplanetary oxygen via mid-infrared collisional absorption." Nature Astronomy 4 (4): 372-376 [10.1038/s41550-019-0977-7] [Journal Article/Letter]

2019. "Quantifying the Evolution of Molecular Production Rates of Comet 21P/Giacobini–Zinner with iSHELL/NASA-IRTF." The Astronomical Journal 158 (6): 254 [10.3847/1538-3881/ab4f6e] [Journal Article/Letter]

2019. "Water Vapor Vertical Profiles on Mars in Dust Storms Observed by TGO/NOMAD." Journal of Geophysical Research: Planets 124 (12): 3482-3497 [10.1029/2019je006109] [Journal Article/Letter]

2019. "A measurement of water vapour amid a largely quiescent environment on Europa." Nature Astronomy [10.1038/s41550-019-0933-6] [Journal Article/Letter]

2019. "A portable miniaturized laser heterodyne radiometer (mini-LHR) for remote measurements of column CH4 and CO2." Applied Physics B 125 (11): 211 [10.1007/s00340-019-7315-8] [Journal Article/Letter]

2019. "IRTF/CSHELL Mapping of Atmospheric HDO, H2O and D/H on Mars during Northern Summer." Icarus 330 204-216 [doi:10.1016/j.icarus.2019.04.007] [Journal Article/Letter]

2019. "The Peculiar Volatile Composition of CO-dominated Comet C/2016 R2 (PanSTARRS)." The Astronomical Journal 158 (3): 128 [10.3847/1538-3881/ab32e4] [Journal Article/Letter]

2019. "Observations of Jupiter Family Comet 252P/LINEAR During a Close Approach to Earth Reveal Large Abundances of Methanol and Ethane." The Astronomical Journal 158 (3): 98 [10.3847/1538-3881/ab289c] [Journal Article/Letter]

2019. "Potential improvements in global carbon flux estimates from a network of laser heterodyne radiometer measurements of column carbon dioxide." Atmospheric Measurement Techniques 12 (4): 2579-2594 [10.5194/amt-12-2579-2019] [Journal Article/Letter]

2019. "Martian dust storm impact on atmospheric H2O and D/H observed by ExoMars Trace Gas Orbiter." Nature 568 (7753): 521-525 [10.1038/s41586-019-1097-3] [Journal Article/Letter]

2019. "No detection of methane on Mars from early ExoMars Trace Gas Orbiter observations." Nature 568 (7753): 517-520 [10.1038/s41586-019-1096-4] [Journal Article/Letter]

2019. "Methane on Mars: New insights into the sensitivity of CH4 with the NOMAD/ExoMars spectrometer through its first in-flight calibration." Icarus 321 671-690 [10.1016/j.icarus.2018.09.021] [Journal Article/Letter]

2019. "ALMA Autocorrelation Spectroscopy of Comets: The HCN/H13CN Ratio in C/2012 S1 (ISON)." The Astrophysical Journal 870 (2): L26 [10.3847/2041-8213/aafb05] [Journal Article/Letter]

2018. "Overview of Primitive Object Volatile Explorer (PrOVE) CubeSat or Smallsat concept." CubeSats and NanoSats for Remote Sensing II [10.1117/12.2321264] [Proceedings]

2018. "The Volatile Composition of Comet C/2017 E4 (Lovejoy) before its Disruption, as Revealed by High-resolution Infrared Spectroscopy with iSHELL at the NASA/IRTF." The Astronomical Journal 156 (2): 68 [10.3847/1538-3881/aace01] [Journal Article/Letter]

2018. "Scientific rationale for Uranus and Neptune in situ explorations." Planetary and Space Science 155 12-40 [10.1016/j.pss.2017.10.005] [Journal Article/Letter]

2018. "Planetary Spectrum Generator: An accurate online radiative transfer suite for atmospheres, comets, small bodies and exoplanets." Journal of Quantitative Spectroscopy and Radiative Transfer 217 86-104 [10.1016/j.jqsrt.2018.05.023] [Journal Article/Letter]

2018. "Solar polarimetry in the K I D2 line : A novel possibility for a stratospheric balloon." Astronomy & Astrophysics 610 A79 [10.1051/0004-6361/201732111] [Journal Article/Letter]

2017. "Line parameters for CO2- and self-broadening in the ν1 band of HD16O." Journal of Quantitative Spectroscopy and Radiative Transfer 203 133-157 [10.1016/j.jqsrt.2017.01.032] [Journal Article/Letter]

2017. "Line parameters for CO2- and self-broadening in the ν3 band of HD16O." Journal of Quantitative Spectroscopy and Radiative Transfer 203 158-174 [10.1016/j.jqsrt.2017.02.020] [Journal Article/Letter]

2017. "A deep search for the release of volcanic gases on Mars using ground-based high-resolution infrared and submillimeter spectroscopy: Sensitive upper limits for OCS and SO2." Icarus 296 1-14 [doi:10.1016/j.icarus.2017.05.014] [Journal Article/Letter]

2017. "Seasonal Changes in Hydrogen Escape From Mars Through Analysis of HST Observations of the Martian Exosphere Near Perihelion." Journal of Geophysical Research: Space Physics 122 (11): 11,756-11,764 [10.1002/2017ja024572] [Journal Article/Letter]

2017. "Measuring molecular abundances in comet C/2014 Q2 (Lovejoy) using the APEX telescope." Monthly Notices of the Royal Astronomical Society 474 (1): 1099-1107 [10.1093/mnras/stx2802] [Journal Article/Letter]

2017. "The 67P/Churyumov–Gerasimenko observation campaign in support of the Rosetta mission." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 375 (2097): 20160249 [10.1098/rsta.2016.0249] [Journal Article/Letter]

2017. "Beyond 3 au from the Sun: The Hypervolatiles CH4, C2H6, and CO in the Distant Comet C/2006 W3 (Christensen)." The Astronomical Journal 153 (5): 241 [10.3847/1538-3881/aa64dd] [Journal Article/Letter]

2017. "ALMA Mapping of Rapid Gas and Dust Variations in Comet C/2012 S1 (ISON):New Insights into the Origin of Cometary HNC." The Astrophysical Journal 838 (2): 147 [10.3847/1538-4357/aa6590] [Journal Article/Letter]

2017. "The Composition of Comet C/2012 K1 (PanSTARRS) and the Distribution of Primary Volatile Abundances Among Comets." The Astronomical Journal 153 (4): 168 [10.3847/1538-3881/aa5d18] [Journal Article/Letter]

2017. "Thermal Physics of the Inner Coma: ALMA Studies of the Methanol Distribution and Excitation in Comet C/2012 K1 (PanSTARRS)." The Astrophysical Journal 837 (2): 177 [10.3847/1538-4357/aa6211] [Journal Article/Letter]

2017. "Ground-based Detection of Deuterated Water in Comet C/2014 Q2 (Lovejoy) at IR Wavelengths." The Astrophysical Journal Letters 836 (2): L25 [10.3847/2041-8213/aa5cb3] [Journal Article/Letter]

2017. "Line parameters for CO2 broadening in the ν2 band of HD16O." Journal of Quantitative Spectroscopy and Radiative Transfer 187 472-488 [10.1016/j.jqsrt.2016.10.004] [Journal Article/Letter]

2016. "DETAILED ANALYSIS OF NEAR-IR WATER (H2O) EMISSION IN COMET C/2014 Q2 (LOVEJOY) WITH THE GIANO/TNG SPECTROGRAPH." The Astrophysical Journal 830 (2): 157 [10.3847/0004-637x/830/2/157] [Journal Article/Letter]

2016. "Expected performances of the NOMAD/ExoMars instrument." Planetary and Space Science 124 94-104 [10.1016/j.pss.2016.03.003] [Journal Article/Letter]

2016. "En Route To Destruction: The Evolution in Composition of Ices in Comet D/2012 S1 (ISON) Between 1.2 and 0.34 Au from the Sun as Revealed at Infrared Wavelengths." The Astrophysical Journal 820 (1): 34 [10.3847/0004-637x/820/1/34] [Journal Article/Letter]

2016. "AN INFRARED SEARCH FOR HDO IN COMET D/2012 S1 (ISON) AND IMPLICATIONS FOR iSHELL." The Astrophysical Journal 816 (2): 101 [10.3847/0004-637x/816/2/101] [Journal Article/Letter]

2016. "Unique Spectroscopy and Imaging of Mars with the James Webb Space Telescope." Publications of the Astronomical Society of the Pacific 128 (1): 018004 [10.1088/1538-3873/128/959/018004] [Journal Article/Letter]

2015. "Science objectives and performances of NOMAD, a spectrometer suite for the ExoMars TGO mission." Planetary and Space Science 119 233-249 [10.1016/j.pss.2015.10.003] [Journal Article/Letter]

2015. "Measuring the Distribution and Excitation of Cometary CH3OH Using ALMA." Proceedings of the International Astronomical Union 11 (A29A): 233-236 [10.1017/s1743921316002957] [Journal Article/Letter]

2015. "THE VOLATILE COMPOSITION OF COMET C/2003 K4 (LINEAR) AT NEAR-IR WAVELENGTHS—COMPARISONS WITH RESULTS FROM THE NANÇAY RADIO TELESCOPE AND FROM THEODIN,SPITZER, ANDSOHOSPACE OBSERVATORIES." The Astrophysical Journal 808 (1): 1 [10.1088/0004-637x/808/1/1] [Journal Article/Letter]

2015. "THE EVOLUTION OF VOLATILE PRODUCTION IN COMET C/2009 P1 (GARRADD) DURING ITS 2011–2012 APPARITION." The Astrophysical Journal 807 (1): 19 [10.1088/0004-637x/807/1/19] [Journal Article/Letter]

2015. "A search for SO2, H2S and SO above Tharsis and Syrtis volcanic districts on Mars using ground-based high-resolution submillimeter spectroscopy." Icarus 253 130-141 [10.1016/j.icarus.2015.02.028] [Journal Article/Letter]

2015. "Evolution of H2O, CO, and CO2 production in Comet C/2009 P1 Garradd during the 2011–2012 apparition." Icarus 250 504-515 [10.1016/j.icarus.2014.12.023] [Journal Article/Letter]

2015. "Strong water isotopic anomalies in the martian atmosphere: Probing current and ancient reservoirs." Science 348 (6231): 218-221 [10.1126/science.aaa3630] [Journal Article/Letter]

2014. "THE INNER COMA OF COMET C/2012 S1 (ISON) AT 0.53 AU AND 0.35 AU FROM THE SUN." The Astrophysical Journal 796 (1): L6 [10.1088/2041-8205/796/1/l6] [Journal Article/Letter]

2014. "GROUND-BASED MULTIWAVELENGTH OBSERVATIONS OF COMET 103P/HARTLEY 2." The Astrophysical Journal 794 (1): 1 [10.1088/0004-637x/794/1/1] [Journal Article/Letter]

2014. "C/2013 R1 (LOVEJOY) AT IR WAVELENGTHS AND THE VARIABILITY OF CO ABUNDANCES AMONG OORT CLOUD COMETS." The Astrophysical Journal 791 (2): 122 [10.1088/0004-637x/791/2/122] [Journal Article/Letter]

2014. "Pre- and post-perihelion observations of C/2009 P1 (Garradd): Evidence for an oxygen-rich heritage?." Icarus 228 167-180 [10.1016/j.icarus.2013.09.001] [Journal Article/Letter]

2014. "ALMA Measurements of the HNC and HC3N Distributions in Titans Atmosphere." ApJ 795 L30 [Journal Article/Letter]

2014. "Mapping the release of volatiles in the inner comae of comets C/2012 F6 (Lemmon) and C/2012 S1 (ISON) using the Atacama Large Millimeter/Submillimeter Array." ApJ 792 L2 [Journal Article/Letter]

2013. "THE UNEXPECTEDLY BRIGHT COMET C/2012 F6 (LEMMON) UNVEILED AT NEAR-INFRARED WAVELENGTHS." The Astronomical Journal 147 (1): 15 [10.1088/0004-6256/147/1/15] [Journal Article/Letter]

2013. "A survey of volatile species in Oort cloud comets C/2001 Q4 (NEAT) and C/2002 T7 (LINEAR) at millimeter wavelengths." Astronomy & Astrophysics 559 A48 [10.1051/0004-6361/201322284] [Journal Article/Letter]

2013. "Modeling of nitrogen compounds in cometary atmospheres: Fluorescence models of ammonia (NH3), hydrogen cyanide (HCN), hydrogen isocyanide (HNC) and cyanoacetylene (HC3N)." Journal of Quantitative Spectroscopy and Radiative Transfer 129 158-168 [10.1016/j.jqsrt.2013.06.010] [Journal Article/Letter]

2013. "Solar fluorescence model of CH3D as applied to comet emission." Journal of Molecular Spectroscopy 291 118-124 [10.1016/j.jms.2013.05.007] [Journal Article/Letter]

2013. "GROUND-BASED INFRARED DETECTIONS OF CO IN THE CENTAUR-COMET 29P/SCHWASSMANN-WACHMANN 1 AT 6.26 AU FROM THE SUN." The Astrophysical Journal 766 (2): 100 [10.1088/0004-637x/766/2/100] [Journal Article/Letter]

2013. "High-resolution infrared spectroscopic measurements of Comet 2P/Encke: Unusual organic composition and low rotational temperatures." Icarus 223 (1): 298-307 [10.1016/j.icarus.2012.11.023] [Journal Article/Letter]

2013. "A sensitive search for organics (CH4, CH3OH, H2CO, C2H6, C2H2, C2H4), hydroperoxyl (HO2), nitrogen compounds (N2O, NH3, HCN) and chlorine species (HCl, CH3Cl) on Mars using ground-based high-resolution infrared spectroscopy." Icarus 223 (1): 11-27 [10.1016/j.icarus.2012.11.013] [Journal Article/Letter]

2013. "A new model for theν1vibrational band of HCN in cometary comae, with application to three comets." Astronomy & Astrophysics 551 A51 [10.1051/0004-6361/201219903] [Journal Article/Letter]

2013. "Evidence for two modes of water release in Comet 103P/Hartley 2: Distributions of column density, rotational temperature, and ortho–para ratio." Icarus 222 (2): 740-751 [10.1016/j.icarus.2012.07.034] [Journal Article/Letter]

2012. "HIGHLY DEPLETED ETHANE AND MILDLY DEPLETED METHANOL IN COMET 21P/GIACOBINI-ZINNER: APPLICATION OF A NEW EMPIRICAL ν2-BAND MODEL FOR CH3OH NEAR 50 K." The Astrophysical Journal 763 (1): 1 [10.1088/0004-637x/763/1/1] [Journal Article/Letter]

2012. "Submillimetric spectroscopic observations of volatiles in comet C/2004 Q2 (Machholz)." Astronomy & Astrophysics 545 A2 [10.1051/0004-6361/201219172] [Journal Article/Letter]

2012. "A multi-instrument study of Comet C/2009 P1 (Garradd) at 2.1AU (pre-perihelion) from the Sun." Icarus 220 (1): 291-295 [10.1016/j.icarus.2012.03.027] [Journal Article/Letter]

2012. "CHEMICAL COMPOSITION OF COMET C/2007 N3 (LULIN): ANOTHER ‘‘ATYPICAL’’ COMET." The Astrophysical Journal 750 (2): 102 [10.1088/0004-637x/750/2/102] [Journal Article/Letter]

2012. "THE CHEMICAL COMPOSITION OF CO-RICH COMET C/2009 P1 (GARRADD) AT R h = 2.4 and 2.0 AU BEFORE PERIHELION." The Astrophysical Journal 748 (1): L13 [10.1088/2041-8205/748/1/l13] [Journal Article/Letter]

2012. "The formation heritage of Jupiter Family Comet 10P/Tempel 2 as revealed by infrared spectroscopy." Icarus 218 (1): 644-653 [10.1016/j.icarus.2012.01.004] [Journal Article/Letter]

2012. "A QUANTUM BAND MODEL OF THE ν3FUNDAMENTAL OF METHANOL (CH3OH) AND ITS APPLICATION TO FLUORESCENCE SPECTRA OF COMETS." The Astrophysical Journal 747 (1): 37 [10.1088/0004-637x/747/1/37] [Journal Article/Letter]

2012. "Water in planetary and cometary atmospheres: H2O/HDO transmittance and fluorescence models." Journal of Quantitative Spectroscopy and Radiative Transfer 113 (3): 202-220 [10.1016/j.jqsrt.2011.11.001] [Journal Article/Letter]

2012. "NIMBUS: the Near-infrared Multi-Band Ultraprecise Spectroimager for SOFIA." SPIE 8446 [10.1117/12.927094] [Journal Article/Letter]

2011. "The molecular composition of Comet C/2007 W1 (Boattini): Evidence of a peculiar outgassing and a rich chemistry." Icarus 216 (1): 227-240 [10.1016/j.icarus.2011.08.024] [Journal Article/Letter]

2011. "HCN and CN in Comet 2P/Encke: Models of the non-isotropic, rotation-modulated coma and CN parent life time." Icarus 215 (1): 153-185 [10.1016/j.icarus.2011.06.038] [Journal Article/Letter]

2011. "Ethane in planetary and cometary atmospheres: Transmittance and fluorescence models of theν7band at 3.3μm." Journal of Geophysical Research 116 (E8): E08012 [10.1029/2010je003794] [Journal Article/Letter]

2011. "EPOXI : COMET 103P/HARTLEY 2 OBSERVATIONS FROM A WORLDWIDE CAMPAIGN." The Astrophysical Journal 734 (1): L1 [10.1088/2041-8205/734/1/l1] [Journal Article/Letter]

2011. "TEMPORAL AND SPATIAL ASPECTS OF GAS RELEASE DURING THE 2010 APPARITION OF COMET 103P/HARTLEY 2." The Astrophysical Journal 734 (1): L7 [10.1088/2041-8205/734/1/l7] [Journal Article/Letter]

2011. "CONSTRAINING VOLATILE ABUNDANCES IN COMET C/2004 Q2 (MACHHOLZ)." Advances in Geosciences - A 6-Volume Set 149-160 [10.1142/9789814355377_0011] [Journal Article/Letter]

2011. "Non-detection of L-band Line Emission from the Exoplanet HD189733b." The Astrophysical Journal 728 18 [Full Text] [10.1088/0004-637X/728/1/18] [Journal Article/Letter]

2011. "Measurement of the isotopic signatures of water on Mars; Implications for studying methane." Planetary and Space Science 59 163 [Full Text] [10.1016/j.pss.2010.06.017] [Journal Article/Letter]

2011. "A Newly Developed Fluorescence Model for C2H6 _5 and Application to Cometary Spectra Acquired with NIRSPEC at Keck II." The Astrophysical Journal 729 135 [Full Text] [10.1088/0004-637X/729/2/135] [Journal Article/Letter]

2011. "Swift-UVOT Grism Spectroscopy of Comets: A First Application to C/2007 N3 (Lulin)." The Astronomical Journal 141 12 [Full Text] [10.1088/0004-6256/141/1/12] [Journal Article/Letter]

2010. "HCN SPECTROSCOPY OF COMET 73P/SCHWASSMANN-WACHMANN 3. A STUDY OF GAS EVOLUTION AND ITS LINK TO CN." The Astrophysical Journal 715 (2): 1258-1269 [10.1088/0004-637x/715/2/1258] [Journal Article/Letter]

2010. "The HCN molecule as a tracer of the nucleus rotation of comet 73P-C/Schwassmann-Wachmann 3." Astronomy and Astrophysics 510 A55 [10.1051/0004-6361/20078882] [Journal Article/Letter]

2010. "The organic composition of Comet C/2000 WM1 (LINEAR) revealed through infrared spectroscopy." Icarus 206 764 [Full Text] [10.1016/j.icarus.2009.09.014] [Journal Article/Letter]

2009. "A Sensitive Search for Deuterated Water in Comet 8p/Tuttle." The Astrophysical Journal Letters 690 L5 [Full Text] [10.1088/0004-637X/690/1/L5] [Journal Article/Letter]

2009. "Strong release of methane on Mars: Evidence of biology or geology?." Geochimica et Cosmochimica Acta Supplement 73 1384 [Full Text] [Journal Article/Letter]

2009. "Strong Release of Methane on Mars in Northern Summer 2003." Science 323 1041 [Full Text] [10.1126/science.1165243] [Journal Article/Letter]

2009. "A multi-wavelength study of parent volatile abundances in Comet C/2006 M4 (SWAN)." Icarus 203 589 [Full Text] [10.1016/j.icarus.2009.05.026] [Journal Article/Letter]

2009. "Comet C/2004 Q2 (Machholz): Parent Volatiles, a Search for Deuterated Methane, and Constraint on the CH4 Spin Temperature." The Astrophysical Journal 699 1563 [Full Text] [10.1088/0004-637X/699/2/1563] [Journal Article/Letter]

2008. "The organic composition of Comet C/2001 A2 (LINEAR) I Evidence for an unusual organic chemistry." Icarus 194 347 [Full Text] [10.1016/j.icarus.2007.10.006] [Journal Article/Letter]

2008. "The Peculiar Volatile Composition of Comet 8P/Tuttle: A Contact Binary of Chemically Distinct Cometesimals?." The Astrophysical Journal 680 L61 [Full Text] [10.1086/589649] [Journal Article/Letter]

2008. "Discovery of multiple bands of isotopic CO2 in the prime spectral regions used when searching for CH4 and HDO on Mars." Journal of Quantitative Spectroscopy & Radiative Transfer, v 109, iss 6, p 883-894 109 883 [Full Text] [10.1016/j.jqsrt.2007.12.016] [Journal Article/Letter]

2008. "Identification of a new band system of isotopic CO2 near 33 μm: Implications for remote sensing of biomarker gases on Mars." Icarus 195 34 [Full Text] [10.1016/j.icarus.2007.11.014] [Journal Article/Letter]

2008. "Discovery of OH in Circumstellar Disks around Young Intermediate-Mass Stars." The Astrophysical Journal 681 L25 [Full Text] [10.1086/590180] [Journal Article/Letter]

2008. "IRCS/Subaru observations of water in the inner coma of Comet 73P-B/Schwassmann Wachmann 3: Spatially resolved rotational temperatures and ortho para ratios." Icarus 196 241 [Full Text] [10.1016/j.icarus.2008.02.023] [Journal Article/Letter]

2008. "The Unusual Volatile Composition of the Halley-Type Comet 8P/Tuttle: Addressing the Existence of an Inner Oort Cloud." The Astrophysical Journal 683 L71 [Full Text] [10.1086/591446] [Journal Article/Letter]

2007. "A Search for Variation in the H2O Ortho-Para Ratio and Rotational Temperature in the Inner Coma of Comet C/2004 Q2 (Machholz)." The Astrophysical Journal 661 L97 [Full Text] [10.1086/518419] [Journal Article/Letter]

2007. "Temporal evolution of parent volatiles and dust in Comet 9P/Tempel 1 resulting from the Deep Impact experiment." Icarus 191 481 [Full Text] [10.1016/j.icarus.2006.10.042] [Journal Article/Letter]

2007. "Depleted Carbon Monoxide in Fragment C of the Jupiter-Family Comet 73P/Schwassmann-Wachmann 3." The Astrophysical Journal 661 L101 [Full Text] [10.1086/518716] [Journal Article/Letter]

2006. "A digital dispersive matching network for SAW devices in chirp transform spectrometers." IEEE Transactions on Microwave Theory and Techniques 54 (4): 1415-1424 [10.1109/tmtt.2006.871244] [Journal Article/Letter]

2006. "Detection of Formaldehyde Emission in Comet C/2002 T7 (LINEAR) at Infrared Wavelengths: Line-by-Line Validation of Modeled Fluorescent Intensities." The Astrophysical Journal 650 470 [Full Text] [10.1086/507118] [Journal Article/Letter]

2006. "The Volatile Composition of the Split Ecliptic comet 73P/Schwassmann-Wachmann 3: A Comparison of Fragments C and B." The Astrophysical Journal 650 L87 [Full Text] [10.1086/508806] [Journal Article/Letter]

2005. "Description and climatology of a new general circulation model of the Martian atmosphere." Journal of Geophysical Research 110 (E11): E11008 [10.1029/2005je002498] [Journal Article/Letter]

2005. "Deep Impact: Observations from a Worldwide Earth-Based Campaign." Science 310 265 [Full Text] [10.1126/science.1118978] [Journal Article/Letter]

2005. "Parent Volatiles in Comet 9P/Tempel 1: Before and After Impact." Science 310 270 [Full Text] [10.1126/science.1119337] [Journal Article/Letter]

2004. "The High Resolution Chirp Transform Spectrometer for the Sofia-Great Instrument." Experimental Astronomy 18 (1-3): 77-91 [10.1007/s10686-005-9004-3] [Journal Article/Letter]

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Marley Fleishman (she/her)
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