Observational planetary astronomer using groundbased and space-based instruments at wavelengths from submillimeter to ultraviolet to investigate atmospheres, including composition, thermal structure, dynamics, and isotope ratios. Currently pursuing volatiles on rocky bodies using both submillimeter and neutron methods.
Timothy A Livengood
(RESEARCH SCIENTIST)
| Email: | timothy.a.livengood@nasa.gov |
| Phone: | 301.286.1552 |
| Org Code: | 693 |
| Address: |
NASA/GSFC Mail Code 693 Greenbelt, MD 20771 |
| Employer: | UNIVERSITY OF MARYLAND AT COLLEGE PARK |
Brief Bio
Research Interests
Lunar volatiles
Solar System: Solar SystemInvestigate diurnal variability in hydrogen-bearing volatiles on the Moon to measure current populations of free volatile species, as well as mapping distributions of volatiles in comparison to topography and measures of mineralogy. Methods currently include neutron remote-sensing and developing submillimeter instrumentation.
Exoplanet analogs
Solar System: Extrasolar PlanetsUse visible-light and near-IR remote sensing of Earth, Moon, Mars as models for terrestrial exoplanets and the properties such planets could - or would not - display in unresolved remote sensing.
Inner planet atmospheres
Solar System: Solar SystemInvestigations of chemical composition, isotope ratios, and wind velocities in the atmosphere of Venus and Mars, using extremely high-resolution mid-infrared spectroscopy. This effort includes laboratory spectroscopy and instrument development to support future advances.
Outer planet atmospheres and aurorae
Solar System: Solar SystemConduct field measurements of composition, temperature, and winds in outer planet stratospheres using extremely high-resolution mid-infrared spectroscopy from groundbased telescopes. Investigations include auroral emissions from Jupiter, Saturn, and other planets, using groundbased infrared and space-based UV spectroscopy and imaging techniques. Work also includes giant-planet atmospheric response to impacts and seasonal variability.
Current Projects
Atmospheric Structure in Jupiter Auroral Atmosphere
Jupiter
Analyze spectroscopy of Jupiter aurora from space-based (Cassini) and groundbased remote-sensing infrared spectroscopy to infer the vertical thermal structure and chemical abundance variations in Jupiter's auroral atmosphere due to energetic particle precipitation. This qwork includes a review of 20+ years of mid-infrared spectroscopy of Jupiter collected in groundbased infrared heterodyne spectroscopy. Preliminary analysis demonstrates solar-cycle effect that is not observed in auroral phenomena on Jupiter at any other wavelength range.
Diurnal Variability in Mars Atmospheric Isotopes
Mars
High-resolution infrared heterodyne spectroscopy of Mars demonstrates variability in 18O-substituted CO2 on Mars that appears to be sensitive to Mars surface temperature. In a recent publication, I argued that the gas-phase fractional abundance of the heavy isotopologue is controlled by low-temperature adsorption and thermal desorption on Mars regolith due to diurnally variable temperatures. These measurements revealed significant enrichment of 18O in Mars atmosphere in mid-afternoon measurements, consistent with the loss to space of the majority of Mars' primordial atmosphere. Investigating archived data that we have collected will enable delving more deeply into diurnal and seasonal effects as well as 13CO2.
Neutron Flux Remote Sensing of Hydrogen in Rocky Regolith
Moons
Developing advanced mapping of lunar neutron flux and advanced neutron detectors. Epithermal neutrons (E~0.4 eV) are locally suppressed where hydrogen is present in the regolith, whereas thermal neutron flux (E<0.4 eV) is suppressed in the presence of high-Z elements and high-energy epithermal (HEE) neutron flux (E~100 keV) is enhanced in the presence of high-Z elements. Distributions of these species can be used to investigate elemental composition of the regolith and compared to other measures of mineralogy to investigate associations with hydrogen content.
Backburner Project: Saturn Seasonal Change
Saturn
Archived mid-infrared spectroscopy from the 1990's through 2010 explores temperature and abundance of the hydrocarbon species ethane in the stratosphere of Saturn during the transition from southern summer to northern summer.
Backburner Project: Saturn Ring Asymmetry
Saturn
Archived mid-infrared imaging from mid-90's shows that near equinox, Saturn rings at western elongation (receding) emit significantly more infrared radiation than at eastern elongation (approaching), more than expected from diurnal thermal variability. Variation is wavelength-dependent.
Backburner Project: Mars as an Exoplanet
Mars
Archived data from the EPOXI mission and Deep Impact spacecraft. Mars near-IR spectra and visible photometry collected in 2009 characterize Mars as a model for an extrasolar terrestrial planet. Data need to be described and reported in the literature. Additional data were collected on diurnally variable near-IR spectra of Mars globally in early 2012.
Backburner Project: Jupiter Mid-IR Auroral Imaging
Jupiter
Low spatial-resolution imaging of Jupiter was collected at mid-IR wavelengths in 1994-1996. These data show nonconjugate auroral brightening, unlike aurora at other wavelengths on Jupiter. Spatial distribution of emission needs to be investigated to compare with location of emission at other wavelengths to characterize the energy distribution of primary particles entering Jupiter's atmosphere, since only high-energy particles can penetrate to hydrocarbon molecules in the stratosphere.
Backburner Project: Jupiter UV Aurora
Jupiter
UV spectroscopy of Jupiter aurora was collected using the International Ultraviolet Explorer (IUE) satellite, in Earth orbit, from 1978 through a 6-week marathon of observations in August-September 1996. About half of all Jupiter spectra with IUE were collected in the final marathon, most of it unpublished.
Submillimeter Solar Observation Lunar Volatiles Experiment
Moons
The Submillimeter Solar Observation Lunar Volatiles Experiment is developing the SSOLVE instrument to measure the abundance of water vapor at the lunar surface from a landed platform by staring at the Sun. H2O, HDO, and OH transitions will be measured as resolved absorption spectra to define the absolute abundance and the D/H ratio. Current estimates based on remote sensing, theoretical estimates, and estimates from exogenous supply rates extend over more than 5 orders of magnitude. A measurement will establish the physical regime that is relevant.
Positions/Employment
Associate Research Scientist
University of Maryland - Goddard Space Flight Center
June 2018 - Present
Leading development of submillimeter instrument for the Moon. Participating scientist in developing advanced neutron detector for space flight, flight mission to investigate lunar water, flight instrument to investigate Enceladus plumes from Saturn orbit. Planetary science investigations using neutron remote sensing of the Moon from the Lunar Reconnaissance Orbiter as well as individual investigator grants for investigations of Mars and Jupiter.
Assistant Research Scientist
University of Maryland - Goddard Space Flight Center
August 2011 - June 2018
Planetary science investigations using neutron remote-sensing of the Moon from the Lunar Reconnaissance Orbiter as well as individual investigator grants for investigations of Mars and Jupiter.
Senior Research Scientist
National Center for Earth and Space Science Education, Tides Foundation - Goddard Space Flight Center
June 2009 - June 2011
Planetary science investigations of solar system atmospheres, including spacebased observations of Earth, Moon, Mars in the EPOXI mission, and groundbased infrared investigations of Venus, Mars, Jupiter, Saturn, Titan. Education and public outreach lead for EPOCh component of EPOXI mission. Classroom and large auditorium presentations on behalf of EPOXI mission.
Assistant Research Scientist
University of Maryland - Goddard Space Flight Center
October 2008 - June 2009
Planetary science investigations of solar system atmospheres, including spacebased observations of Earth, Moon, Mars in the EPOXI mission, and groundbased infrared investigations of Venus, Mars, Jupiter, Saturn, Titan. Education and public outreach lead for EPOCh component of EPOXI mission. Classroom and large auditorium presentations on behalf of EPOXI mission.
Senior Research Scientist
National Center for Earth and Space Science Education, Universities Space Research Association - Goddard Space Flight Center
July 2005 - September 2008
Planetary science investigations of solar system atmospheres, including spacebased observations of Earth and Moon in the EPOXI mission, and groundbased infrared investigations of Venus, Mars, Jupiter, Saturn, Titan. Education and public outreach lead for EPOCh component of EPOXI mission. Education and public outreach role in developing K-13 education modules, verifying scientific accuracy, leading teams to support communities in Journey through the Universe community education initiative, leading space science education workshops of 20-200 teachers, making classroom presentations on space science and large-auditorium presentations.
Space Science Researcher
Challenger Center for Earth and Space Science Education - Goddard Space Flight Center and Alexandria, VA
October 1999 - June 2005
Planetary science investigations of solar system atmospheres in groundbased infrared investigations of Venus, Mars, Jupiter, Saturn, Titan. Education and public outreach role in developing K-13 education modules, verifying scientific accuracy, leading teams to support communities in Journey through the Universe community education initiative, leading space science education workshops of 20-200 teachers, making classroom presentations on space science and large-auditorium presentations.
Assistant Research Scientist
University of Maryland - Goddard Space Flight Center
October 1994 - December 1999
Planetary science investigations of solar system atmospheres in groundbased infrared investigations of Venus, Mars, Jupiter, Saturn, Titan.
Resident Research Associate
National Research Council, National Academy of Sciences - Goddard Space Flight Center
October 1991 - September 1994
Planetary science investigations of solar system atmospheres in groundbased infrared investigations of Jupiter aurora.
Teaching Experience
2000 through present: interactive presentations on space science to audiences of all sizes. Co-developer of three education modules for Earth and space sciences at K-13 range, inclduing adoption by Washington, DC as 6th-grade space science curriculum in 2005.
2024 Fall - Taught Introduction to Solar System Astronomy for non-majors at UMD as a class in mission design exercises.
2024 Fall - Taught Stars and Stellar Systems for non-majors at UMD.
2023 Fall - Taught Introduction to Solar System Astronomy for non-majors at UMD as a class in mission design exercises.
2023 Spring - Taught Introduction to Solar System Astronomy for non-majors at UMD as a class in mission design exercises.
2022 Fall - Taught Introduction to Solar System Astronomy for non-majors at UMD as a class in mission design exercises.
2019 Spring - Taught Introduction to Solar System Astronomy for non-majors at UMD as a class in mission design exercises.
2018 Fall - Taught Introduction to Solar System Astronomy for non-majors at UMD as a class in mission design exercises.
2015 Spring - Taught Introduction to Solar System Astronomy for non-majors at UMD.
2002 Spring - Taught Introductory Physics at Montgomery Community College in Silver Spring, MD.
Education
1992, PhD, The Johns Hopkins University, Baltimore, MD (requirements completed Sep 1991). "The Jovian Ultraviolet Aurora Observed with the IUE Spacecraft: Brightness and Color Distribution with Longitude", advisor H. Warren Moos.
1987, MA, The Johns Hopkins University, Baltimore, MD.
1984, BA, Washington University in St. Louis. Major: physics, minor: mathematics.
Professional Societies
Division for Planetary Sciences, American Astronomical Society
1992 - Present
American Geophysical Union
1992 - Present
American Association for the Advancement of Science
2012 - Present
Folklore Society of Greater Washington
Lifetime member, At-Large Board member
1998 - Present
National Storytelling Network
2000 - Present
Professional Service
NASA Solar System Observations proposal review.
NASA Lunar Data Analysis Program proposal review.
NASA Cassini/New Horizons Data Analysis Program proposal review.
NASA Extrasolar Research Program proposal review, Sub-panel chair, twice
NASA Mars Fundamental Research Program proposal review
NASA Planetary Atmospheres Program proposal review
NASA Planetary MIssion Data Analysis Program proposal review
NCESSE Student Spaceflight Experiments Program proposal review, panel chair, 11 times
1994 DPS Meeting, local organizing committee member
Manuscript reviewer for Icarus, Journal of Geophysical Research, Technical Soaring
Awards
2013, NASA Award for Exceptional Achievement For Science (Team, LRO)
2010 NASA Group Achievement Award, GSFC Middle School Week
2009 NASA Group Achievement Award: EPOXI Mission
2009 NASA/GSFC Solar System Exploration Division Peer Award
1991–1994 NAS/NRC Research Associate
Grants
Remote Exploration of Mars Stable Isotopes: a Sign of the Missing Atmosphere
Planetary Astronomy Program - NASA - Awarded: 2014-01-17
Dates: 2014-04-02 - 2017-04-01
Variability in Jupiter's Aurora from Multi-decadal Infrared Data
Planetary Atmospheres Program - NASA - Awarded: 2012-02-23
Dates: 2012-10-01 - 2015-09-30
Remote Exploration of Mars Atmosphere in the Era of Mars Science Laboratory
Planetary Astronomy Program - NASA - Awarded: 2012-03-28
Dates: 2011-10-01 - 2012-09-30
LEND Investigations of Lunar Volatiles
Lunar Reconnaissance Orbiter – Lunar Exploration Neutron Detector - NASA Goddard Space Flight Center - Awarded: 2011-08-01
Dates: 2011-08-15
Coverage: 0.5
EPOXI: Extrasolar Planetary Observation and Characterization and Deep Impact Extended Investigation
Discovery Program – EPOXI (component: Extrasolar Planets Observation adn Characterization, EPOCh) - NASA - Awarded: 2007-06-01
Dates: 2008-01-02 - 2011-07-01
Picture this SELFI: Submillimeter Encladus Life Fundamentals Investigation
NASA/MATISSE – Picture this SELFI: Submillimeter Enceladus Life Fundamentals Instrument - NASA - Awarded: 2017-09-04
Dates: 2017-09-04 - 2020-09-03
Coverage: 0.05
Surface and Exosphere Alterations by Landing (SEAL)
NASA/NPLP – Surface and Exosphere Alteration by Landing (SEAL) - NASA (NPLP) - Awarded: 2019-04-01
Dates: 2019-04-01 - 2022-03-31
Coverage: 0.1
Submillimeter Solar Observation Lunar Volatiles Experiment (SSOLVE)
DALI – Submillimeter Solar Observation Lunar Volatiles Experiment (SSOLVE) - NASA (NNH18ZDA001N-DALI) - Awarded: 2018-10-17
Dates: 2019-05-01 - 2022-04-29
Coverage: 0.25
Amount 3600000
Detecting Objects' Water through Spatial Epithermal-neutron Response (DOWSER)
NASA/PICASSO – Detecting Objects' Water through Spatial Epithermal-neutron Response (DOWSER) - NASA (NNH18ZDA001N-PICASSO) - Awarded: 2019-05-01
Dates: 2019-05-01 - 2022-04-29
Coverage: 0.1
Other Professional Information
Co-PI of final IUE Key Project, “Completion of IUE Jovian Studies”, with R. M. Prangé.
Leadership team for European Southern Observatory and IUE Shoemaker-Levy 9 science teams.
Member of NASA/IRTF SL9 science team.
Professional storyteller, conveying scientific information and awareness through story.
Special Experience
Professional storyteller. Public science presentations for audiences from 3 to 1700. Bicycled down Mauna Kea at high speed (but never up!).
Publications
Refereed
2024. "CLEW (compact lunar explorer for water): state of the art IR spectrometer for a lunar CubeSat orbiter beyond BIRCHES." Proceedings of the SPIE: CubeSats, SmallSats, and Hosted Payloads for Remote Sensing VIII 13146 1314607 [10.1117/12.3028912] [Proceedings]
2024. "Global mapping of lunar surface water and hydroxyl in context." Proceedings of the SPIE: CubeSats, SmallSats, and Hosted Payloads for Remote Sensing VIII 13146 1314608 [10.1117/12.3028922] [Proceedings]
2024. "Evidence for Widespread Hydrogen Sequestration within the Moon’s South Pole Cold Traps." The Planetary Science Journal 5 (10): 217 [10.3847/psj/ad5b55] [Journal Article/Letter]
2024. "PReSSiC: Planetary Remote Sensing using SiC detectors." 243rd Meeting of the American Astronomical Society, id. 329.05. Bulletin of the American Astronomical Society Vol. 56 (No. 2 e-id): [Proceedings]
2023. "Next generation compact IR spectrometers for the Moon." Proceedings of the SPIE: CubeSats, SmallSats, and Hosted Payloads for Remote Sensing VII 12689 12689-09 [10.1117/12.2679138] [Proceedings]
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. "Terrestrial Planet Optical Phase Curves. I. Direct Measurements of the Earth." The Astronomical Journal 163 (1): 5 [10.3847/1538-3881/ac3234] [Journal Article/Letter]
2020. "Comparative VIS and NIR Raman and FTIR Spectroscopy of Lunar Analog Samples." Europlanet Science Congress 2020, online [10.5194/epsc2020-427] [Proceedings]
2020. "Lunar Cellular Network Neutron Spectrometer." Lunar Surface Science Workshop (LPI Contrib No. 2241) (id. 5147): [Proceedings]
2020. "Correlated Raman and Reflectance Spectroscopy for In Situ Lunar Resource Exploration." Lunar Surface Science Workshop (LPI Contrib No. 2241) id. 5113 [Proceedings]
2020. "Moonba, a Micro-Rover for a Targeted Investigation of Lunar Surface Dust." Lunar Surface Science Workshop (LPI Contrib No. 2241) id. 5092 [Proceedings]
2020. "SNFLER: Surface Neutron Flux with Lunar Empirical Ratio." Lunar Surface Science Workshop (LPI Contrib No. 2241) id. 5060 [Proceedings]
2020. "Submillimeter Solar Observation Lunar Volatiles Experiment at the South Pole (SSOLVE@SP)." Lunar Surface Science Worksop 2020 (LPI Contrib No. 2241) id. 5058 [Proceedings]
2020. "Compact Lunar Mineralogy Imager (CLuMI)." Lunar Surface Science Workshop 2020 (LPI Contrib. No. 2241) [Proceedings]
2020. "The CORGIE (Confirming Orbital Remote-Sensing with Ground Information Experiments) Consortium." Lunar Surface Science Workshop 2020 (LPI Contrib. no 2241) [Proceedings]
2020. "Evaluation of a method to retrieve temperature and wind velocity profiles of the Venusian nightside mesosphere from mid-infrared CO2 absorption line observed by heterodyne spectroscopy." Earth, Planets and Space 72 (1): 60 [10.1186/s40623-020-01188-0] [Journal Article/Letter]
2020. "Evidence for diurnally varying enrichment of heavy oxygen in Mars atmosphere." Icarus 335 113387 [10.1016/j.icarus.2019.113387] [Journal Article/Letter]
2019. "Earthshine as an illumination source at the Moon." Icarus 321 841-856 [10.1016/j.icarus.2018.12.025] [Journal Article/Letter]
2018. "Background and lunar neutron populations detected by LEND and average concentration of near-surface hydrogen near the Moon's poles." Planetary and Space Science 162 89–104 [10.1016/j.pss.2017.12.004] [Journal Article/Letter]
2018. "Crater age and hydrogen content in lunar regolith from LEND neutron data." Planetary and Space Science 162 105–112 [10.1016/j.pss.2017.08.001] [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. "Exoplanet Science Priorities from the Perspective of Internal and Surface Processes for Silicate and Ice Dominated Worlds." National Academy of Sciences 2018 Exoplanet Science Strategy White Paper [Other]
2018. "Long term evolution of temperature in the venus upper atmosphere at the evening and morning terminators." Icarus 299 370-385 [10.1016/j.icarus.2017.07.030] [Journal Article/Letter]
2017. "Hydrogen distribution in the lunar polar regions." Icarus 283 20-30 [10.1016/j.icarus.2016.06.002] [Journal Article/Letter]
2016. "The variations of neutron component of lunar radiation background from LEND/LRO observations." Planetary and Space Science 122 53-65 [10.1016/j.pss.2016.01.006] [Journal Article/Letter]
2015. "Thermal structure of Venus׳ nightside mesosphere as observed by infrared heterodyne spectroscopy at 10μm." Planetary and Space Science 113-114 359-368 [10.1016/j.pss.2015.01.021] [Journal Article/Letter]
2015. "Moonshine: Diurnally varying hydration through natural distillation on the Moon, detected by the Lunar Exploration Neutron Detector (LEND)." Icarus 255 100-115 [10.1016/j.icarus.2015.04.004] [Journal Article/Letter]
2015. "Evidence for the sequestration of hydrogen-bearing volatiles towards the Moon’s southern pole-facing slopes." Icarus 255 88-99 [10.1016/j.icarus.2014.10.001] [Journal Article/Letter]
2014. "Science goals and mission concept for the future exploration of Titan and Enceladus." Planetary and Space Science 104 59-77 [10.1016/j.pss.2014.10.002] [Journal Article/Letter]
2013. "ERRATUM: “COLORS OF A SECOND EARTH. II. EFFECT OF CLOUDS ON PHOTOMETRIC CHARACTERIZATION OF EARTH-LIKE EXOPLANETS” (2011, ApJ, 738, 184)." The Astrophysical Journal 771 (2): 139 [10.1088/0004-637x/771/2/139] [Journal Article/Letter]
2013. "A Search for Methane in the Atmosphere of Mars using Ground-Based Mid Infrared Heterodyne Spectroscopy." J. Mol. Spectrosc. 291 98-101 10.1016/2013.05.009. [Journal Article/Letter]
2012. "Direct wind measurements from November 2007 in Venus’ upper atmosphere using ground-based heterodyne spectroscopy of CO2 at 10μm wavelength." Icarus 217 (2): 863-874 [10.1016/j.icarus.2011.03.019] [Journal Article/Letter]
2012. "EPOXI Mars Obs - HRII Raw Spectra V1.0." NASA Planetary Data System 8215 [Dataset]
2012. "EPOXI Mars Obs - HRIV Raw Images V1.0." NASA Planetary Data System 8221 [Dataset]
2012. "EPOXI Mars Obs - HRIV Calibrated Images V1.0." NASA Planetary Data System 8227 [Dataset]
2012. "EPOXI Mars Obs - MRI Raw Images V1.0." NASA Planetary Data System 8233 [Dataset]
2012. "EPOXI Mars Obs - MRI Calibrated Images V1.0." NASA Planetary Data System 8234 [Dataset]
2012. "Thermospheric/Mesospheric Temperatures on Venus: Results from Ground-Based High-Resolution Spectroscopy of CO2 in 1990/91 and Comparison to Results from 2009 and between Other Techniques." Icarus 217 856-862 [10.1016/j.icarus.2011.07.015] [Journal Article/Letter]
2011. "Properties of an Earth-Like Planet Orbiting a Sun-Like Star: Earth Observed by the EPOXI Mission." Astrobiology 11 (9): 907-930 [10.1089/ast.2011.0614] [Journal Article/Letter]
2011. "COLORS OF A SECOND EARTH. II. EFFECTS OF CLOUDS ON PHOTOMETRIC CHARACTERIZATION OF EARTH-LIKE EXOPLANETS." The Astrophysical Journal 738 (2): 184 [10.1088/0004-637x/738/2/184] [Journal Article/Letter]
2011. "Earth as an Extrasolar Planet: Earth Model Validation Using EPOXI Earth Observations." Astrobiology 11 (5): 393-408 [10.1089/ast.2011.0642] [Journal Article/Letter]
2011. "Modification of Jupiter’s stratosphere three weeks after the 2009 impact." Icarus 213 (1): 195-200 [10.1016/j.icarus.2011.02.008] [Journal Article/Letter]
2011. "ROTATIONAL VARIABILITY OF EARTH'S POLAR REGIONS: IMPLICATIONS FOR DETECTING SNOWBALL PLANETS." The Astrophysical Journal 731 (1): 76 [10.1088/0004-637x/731/1/76] [Journal Article/Letter]
2011. "Views from EPOXI: Colors in Our Solar System as an Analog for Extrasolar Planets." The Astrophysical Journal 729 130 [Full Text] [10.1088/0004-637X/729/2/130] [Journal Article/Letter]
2011. "System Parameters, Transit Times, and Secondary Eclipse Constraints of the Exoplanet Systems HAT-P-4, TrES-2, TrES-3, and WASP-3 from the NASA EPOXI Mission of Opportunity." The Astrophysical Journal 726 94 [Full Text] [10.1088/0004-637X/726/2/94] [Journal Article/Letter]
2011. "A Search for Additional Planets in Five of the Exoplanetary Systems Studied by the NASA EPOXI Mission." The Astrophysical Journal 732 41 [Full Text] [10.1088/0004-637X/732/1/41] [Journal Article/Letter]
2011. "Modification of Jupiter's stratosphere three weeks after the 2009 impact." Icarus 213 195 [Full Text] [10.1016/j.icarus.2011.02.008] [Journal Article/Letter]
2010. "High Spectral Resolution Infrared Studies of Titan: Winds, Temperature and Composition." Planetary and Space Science 58 715-1723 [10.1016/2010.08.004] [Journal Article/Letter]
2010. "A Search for Additional Planets in the NASA EPOXI Observations of the Exoplanet System GJ 436." The Astrophysical Journal 716 1047 [Full Text] [10.1088/0004-637X/716/2/1047] [Journal Article/Letter]
2009. "Comparison of HIPWAC and Mars Express SPICAM observations of ozone on Mars 2006–2008 and variation from 1993 IRHS observations." Icarus 203 (1): 20-27 [10.1016/j.icarus.2009.05.005] [Journal Article/Letter]
2009. "ALIEN MAPS OF AN OCEAN-BEARING WORLD." The Astrophysical Journal 700 (2): 915-923 [10.1088/0004-637x/700/2/915] [Journal Article/Letter]
2009. "TandEM: Titan and Enceladus mission." Experimental Astronomy 23 893 [Full Text] [10.1007/s10686-008-9103-z] [Journal Article/Letter]
2008. "Venus upper atmosphere winds from ground-based heterodyne spectroscopy of CO2 at wavelength." Planetary and Space Science 56 (10): 1399-1406 [10.1016/j.pss.2008.05.006] [Journal Article/Letter]
2008. "The NASA EPOXI mission of opportunity to gather ultraprecise photometry of known transiting exoplanets." IAU 4 (S253): 301 [10.1017/s1743921308026525] [Journal Article/Letter]
2008. "Preliminary Results on HAT-P-4, TrES-3, XO-2, and GJ 436 from the NASA EPOXI Mission." IAU 4 (S253): 470 [10.1017/s1743921308026963] [Journal Article/Letter]
2008. "Venus upper atmosphere winds from heterodyne spectroscopy of CO2 at 10µm wavelength." Planetary and Space Sciences 56 1399-1406 [Journal Article/Letter]
2007. "Strong Solar Control of Infrared Aurora on Jupiter." Proc. Magnetospheres of the Outer Planets Meeting, San Antonio Texas, June 25-29, 2007 [Full Text] [Journal Article/Letter]
2006. "High-resolution infrared spectroscopy of ethane in Titan's stratosphere in the Huygens epoch." J. Geophys. Res.-Planets 111 E11S90 [10.1029/2005JE002669] [Journal Article/Letter]
2006. "Overview of the coordinated ground-based observations of Titan during the Huygens mission." Journal of Geophysical Research 111 (E7): E07S01 [10.1029/2005je002640] [Journal Article/Letter]
2006. "Stratospheric global winds on Titan at the time of Huygens descent." Journal of Geophysical Research 111 (E7): E07S03 [10.1029/2005je002630] [Journal Article/Letter]
2006. "Ozone abundance on Mars from infrared heterodyne spectra." Icarus 183 (2): 396-402 [10.1016/j.icarus.2006.03.012] [Journal Article/Letter]
2006. "Ozone Abundance on Mars from Infrared Heterodyne Spectra I: Acquisition, Retrieval, and Anticorrelation with Water Vapor." Icarus 181 419-431 [10.1016/j.icarus] [Journal Article/Letter]
2006. "Ozone abundance on Mars from infrared heterodyne spectra II: Validating photochemical models." Icarus 183 396-402 [10.1016/j.icarus.2006.03.012] [Journal Article/Letter]
2006. "Characterization of zonal winds in the stratosphere of Titan with UVES, II: Observations coordinated with the Huygens Probe entry." JGR-Planets 111 E08S90 [10.1029/2005JE002617] [Journal Article/Letter]
2005. "Titan's stratospheric zonal wind, temperature, and ethane abundance a year prior to Huygens insertion." Geophysical Research Letters 32 (22): L22205 [10.1029/2005gl023897] [Journal Article/Letter]
2005. "Titan’s Stratospheric Zonal Wind, Temperature and Ethane Abundance a Year Prior to Huygens Insertion." Geophys. Res. Lett. 32 L22205 [10.1029/2005GL023897] [Journal Article/Letter]
2002. "Improved Determination of Ethane (C2H6) Abundance in Titan's Stratosphere." Icarus 157 (1): 249-253 [10.1006/icar.2002.6823] [Journal Article/Letter]
2001. "Direct measurement of winds on Titan." Geophysical Research Letters 28 (12): 2361-2364 [10.1029/2000gl012617] [Journal Article/Letter]
2000. "Physical Properties of the Nucleus of Comet 2P/Encke." Icarus 147 (1): 145-160 [10.1006/icar.2000.6431] [Journal Article/Letter]
1999. "Refraction by Earth's Atmosphere near 12 Microns." Publications of the Astronomical Society of the Pacific 111 (758): 512-521 [10.1086/316347] [Journal Article/Letter]
1997. "Ethane abundance on Titan." Planetary and Space Science 45 (8): 931-939 [10.1016/s0032-0633(97)00086-x] [Journal Article/Letter]
1997. "Infrared Observations Of Dust Emission From Comet Hale-Bopp." Earth, Moon, and Planets 78 (1/3): 251-257 [10.1023/a:1006261303055] [Journal Article/Letter]
1997. "Comparison of IUE and HST diagnostics of the Jovian Aurorae." Journal of Geophysical Research 102 (E4): 9289 [10.1029/96je03304] [Journal Article/Letter]
1996. "Impact Seismology: A Search for Primary Pressure Waves Following Impacts A and H." Icarus 121 (2): 331-340 [10.1006/icar.1996.0091] [Journal Article/Letter]
1996. "Stratospheric Ammonia on Jupiter after the SL9 Collision." Icarus 121 (2): 431-441 [10.1006/icar.1996.0098] [Journal Article/Letter]
1995. "Far-UV emissions from the SL9 impacts with Jupiter." Geophysical Research Letters 22 (17): 2425-2428 [10.1029/95gl02422] [Journal Article/Letter]
1995. "Collision of comet Shoemaker-Levy 9 with Jupiter observed by the NASA infrared telescope facility." Science 267 (5202): 1277-1282 [10.1126/science.7871423] [Journal Article/Letter]
1995. "Response of the Io plasma torus to comet Shoemaker-Levy 9." Science 267 (5202): 1313-1317 [10.1126/science.7871429] [Journal Article/Letter]
1993. "Correlated variations of UV and radio emissions during an outstanding Jovian auroral event." Journal of Geophysical Research 98 (E10): 18779 [10.1029/93je01802] [Journal Article/Letter]
1993. "Temperature and abundances in the Jovian auroral stratosphere: 1. Ethane as a probe of the millibar region." Journal of Geophysical Research 98 (E10): 18813 [10.1029/93je01043] [Journal Article/Letter]
1993. "Temperature and abundances in the Jovian auroral stratosphere: 2. Ethylene as a probe of the microbar region." Journal of Geophysical Research 98 (E10): 18823 [10.1029/93je01332] [Journal Article/Letter]
1993. "The Beta Pictoris circumstellar disk. XV - Highly ionized species near Beta Pictoris." Astronomy & Astrophysics 267 187-193 [Journal Article/Letter]
1992. "Jovian ultraviolet auroral activity, 1981–1991." Icarus 97 (1): 26-45 [10.1016/0019-1035(92)90055-c] [Journal Article/Letter]
1992. "The Jovian ultraviolet aurora observed with the IUE spacecraft: Brightness and color distribution with longitude." [Other]
1990. "Jupiter's north and south polar aurorae with IUE data." Geophysical Research Letters 17 (12): 2265-2268 [10.1029/gl017i012p02265] [Journal Article/Letter]
1990. "Long-term study of longitudinal dependence in primary particle precipitation in the north Jovian aurora." Journal of Geophysical Research 95 (A7): 10375 [10.1029/ja095ia07p10375] [Journal Article/Letter]
Non-Refereed
2021. "Ice Giant Atmospheric Science." BAAS 53 (4): e-id. 264 [10.3847/25c2cfeb.97316a54] [Journal Article/Letter]
2021. "Mission to Characterize Volatiles in Old, Cold, Permanently Shadowed Regions on the Moon." BAAS, Planetary/Astrobiology Decadal Survey Whitepapers 53 (4): e-id. 365 [10.3847/25c2cfeb.f3dc6df2] [Journal Article/Letter]
2021. "Jupiter System Observatory at Sun-Jupiter Lagrangian Point One." BAAS, Planetary/Astrobiology Decadal Survey Whitepapers 53 (4): e-id. 358 [10.3847/25c2cfeb.e19d6296] [Journal Article/Letter]
2021. "A Next Generation Lunar Orbiter Mission." Vol. 53, Issue 4 (Planetary/Astrobiology Decadal Survey Whitepapers) 53 (4): e-id. 330 [10.3847/25c2cfeb.8f28f012] [Journal Article/Letter]
2021. "The Magnetosphere of Jupiter: Moving from Discoveries Towards Understanding." Vol. 53, Issue 4 (Planetary/Astrobiology Decadal Survey Whitepapers) 53 (4): e-id. 257 [10.3847/25c2cfeb.9caa18e1] [Journal Article/Letter]
2021. "Retrieving Earth's phase curve." AASTCS8, Habitable Worlds 2021, id. 1119. Bulletin of the American Astronomical Society 53 (3): e-id 2021n3i1119 [Other]
Talks, Presentations and Posters
Other
Retrieving Earth's phase curve
April 2021
De Cock, R., S. Dineshkumar, T. Hewagama, C. Lisse and T. Livengood (2021). Retrieving Earth's phase curve. AASTCS8, Habitable Worlds 2021. virtual, Bulletin of the American Astronomical Society 53, id 1119.
Compact Lunar Hydration and Mineralogy Explorer (CLuHME)
November 2020
Hewagama, T., S. Aslam, D. M. Bower, D. E. Jennings, M. D. Jhabvala, T. A. Livengood, G. L. Villanueva, F. Cepollina, N. E. Petro and K. E. Young (2020). Compact Lunar Hydration and Mineralogy Explorer (CLuHME). AAS Division of Planetary Sciences #52. virtual, Bulletin of the American Astronomical Society 52, e-id 2020n6i001p10.
Comparative VIS and NIR Raman and FTIR Spectroscopy of Lunar Analog Samples
November 2020
Bower, D., P. Misra, M. Peterson, M. Howard, T. Hewagama, N. Gorius, S. Li, S. Aslam, T. Livengood, A. McAdam and J. Kolasinski (2020). Comparative VIS and NIR Raman and FTIR Spectroscopy of Lunar Analog Samples. Europlanet Science Congress. virtual, id. EPSC2020-427.
SOLVENT - Simultaneous Observations of the Lunar Volatile EnvironmeNT
March 27, 2018
SOLVENT will make Simultaneous Observations of the Lunar Volatile EnviornmeNT in complementary wavelength regimes, to measure the abundance of water and hydroxyl in the illuminated lunar surface and in the free space above it.