Sciences and Exploration Directorate

Rosemary Margaret Killen


Rosemary Margaret Killen's Contact Card & Information.
Phone: 301.286.6574
Org Code: 695
Mail Code 695
Greenbelt, MD 20771

Brief Bio

Dr. Killen has published extensively on the exospheres of Mercury and the Moon.

Dr. Killen is PI for the SSERVI Team, LEADER, "Lunar Environment and Dynamics for Exploration Research". LEADER is a consortium of 33 scientists in eight institutions studying the environment of the Moon, the effects of human exploration on the lunar environment and the effects of the lunar environment on humans and their systems on and around the Moon.

She was a Participating Scientist on the MESSENGER Mission to Mercury, Deputy PI on the DREAM and DREAM2 teams of the Solar System Exploration Virtual Institute, and Co-I on STROFIO, a mass spectrometer on Bepi-Colombo. She has observed Mercury, the Moon and the Galilean satellites at many major observatories. She is interested in the physics of space weathering and the interactions of the solar wind plasma with the surfaces of planets and satellites to produce exospheres. She has over 100 papers published in the refereed literature and almost 200 abstracts presented at scientific meetings.

Research Interests

Research Scientist

Solar System: Solar System

I study the exospheres of the Moon and Mercury via ground-based spectroscopy, space-based ultraviolet spectroscopy, and mathematical modeling using analytical and Monte Carlo  models.

Current Projects

LEADER TEAM of SSERVI (Solar System Exploration and Research Virtual Institute), PI; DREAM2 TEAM of SSERVI (Solar System Exploration and Research Virtual Institute), Deputy PI; Ground-based coronagraphic observations of the lunar sodium exosphere, PI; Team member on the STROFIO mass spectrometer team for the ESA Bepi-Colombo mission to Mercury; Discovery Data Analysis for MESSENGER MASCS Data


I study planetary exospheres (tenuous atmospheres) throughout our solar system, concentrating on Mercury and the Moon.


Research Scientist

NASA - Goddard Space Flight Center, Greenbelt, Maryland

June 2009 - Present

My roles include research in the exospheres of Mercury and the Moon. I am PI of the SSERVI team, LEADER, that studies the lunar environment and dynamics for exploration research. We have four teams studying radiation, dust, exospheres and plasmas, respectively. We have a laboratory component to test the effect of solar wind on surfaces to simulate the surfaces of the Moon and airless planetary bodies. Another laboratory component involves the production and evolution of dust on surfaces such as that of the Moon.


• Rice University, Space Physics and Astronomy, Ph.D. 1987
• University of Texas at Austin, Astronomy, MS 1975
• Southwestern University, Mathematics and Physics, BS 1971

Professional Societies

American Astronomical Society Division for Planetary Science; American Geophysical Society; International Astronomical Union

Full member

1985 - Present

International Astronomical Union

2007 - Present


Robert H Goddard Group Achievement Award for Science for SSERVI Team DREAM2, 2019

NASA Group Achievement Award for MESSENGER, 2018

Robert H Goddard Exceptional Achievement for Science, 2018

Solar System Division Peer Award, 2014



2024. "Absolute doubly differential angular sputtering yields for 20 keV Kr+ on polycrystalline Cu." Journal of Applied Physics 135 (3): [10.1063/5.0184417] [Journal Article/Letter]

2023. "In Situ Optimized Substrate Witness Plates: Ground Truth for Key Processes on the Moon and Other Planets." Earth and Space Science 10 (9): [10.1029/2023ea003004] [Journal Article/Letter]

2023. "Lunar Solar Occultation Explorer (LunaSOX)." Frontiers in Astronomy and Space Sciences 10 [10.3389/fspas.2023.1163517] [Journal Article/Letter]

2023. "Establishing a Best Practice for SDTrimSP Simulations of Solar Wind Ion Sputtering." The Planetary Science Journal 4 (4): 67 [10.3847/psj/acc587] [Journal Article/Letter]

2023. "Erratum: “The Influence of Surface Binding Energy on Sputtering in Models of the Sodium Exosphere of Mercury” (2022, PSJ, 3, 139)." The Planetary Science Journal 4 (4): 78 [10.3847/psj/acc534] [Journal Article/Letter]

2023. "Latitudinal and radial dependence of the lunar sodium exospheric temperature and linewidths." Icarus 115560 [10.1016/j.icarus.2023.115560] [Journal Article/Letter]

2022. "Updated Photon Scattering Coefficients (g_values) for Mercury’s Exospheric Species." The Astrophysical Journal Supplement Series 263 (2): 37 [10.3847/1538-4365/ac9eab] [Journal Article/Letter]

2022. "The Influence of Surface Binding Energy on Sputtering in Models of the Sodium Exosphere of Mercury." The Planetary Science Journal 3 (6): 139 [10.3847/psj/ac67de] [Journal Article/Letter]

2022. "Comparative Na and K Mercury and Moon Exospheres." Space Science Reviews 218 (1): 2 [10.1007/s11214-022-00871-w] [Journal Article/Letter]

2022. "Solar Wind Ion Sputtering of Sodium from Silicates Using Molecular Dynamics Calculations of Surface Binding Energies." The Astrophysical Journal Letters 925 (1): L6 [10.3847/2041-8213/ac42d8] [Journal Article/Letter]

2021. "Sputtering of surfaces by ion irradiation: A comparison of molecular dynamics and binary collision approximation models to laboratory measurements." Journal of Applied Physics 130 (1): 013302 [10.1063/5.0051073] [Journal Article/Letter]

2021. "Lunar Atmosphere: Source and Loss Processes." Encyclopedia of Lunar Science 1000 [Article in Book]

2021. "Volatiles and Refractories in Surface-Bounded Exospheres in the Inner Solar System." Space Science Reviews 217 (5): 61 [10.1007/s11214-021-00833-8] [Journal Article/Letter]

2021. "Lifetime of a transient atmosphere produced by lunar volcanism." Icarus 359 114304 [10.1016/j.icarus.2021.114304] [Journal Article/Letter]

2021. "SERENA: Particle Instrument Suite for Determining the Sun-Mercury Interaction from BepiColombo." Space Science Reviews 217 (1): 11 [10.1007/s11214-020-00787-3] [Journal Article/Letter]

2020. "Investigating Mercury’s Environment with the Two-Spacecraft BepiColombo Mission." Space Science Reviews 216 (5): 93 [10.1007/s11214-020-00712-8] [Journal Article/Letter]

2019. "Meteoroids: Sources of Meteors on Earth and Beyond: Extraterrestrial Meteors." [Book]

2019. "Was the Sun a Slow Rotator? Sodium and Potassium Constraints from the Lunar Regolith." The Astrophysical Journal 876 (1): L16 [10.3847/2041-8213/ab18fb] [Journal Article/Letter]

2019. "The lunar neon exosphere seen in LACE data." Icarus 329 246-250 [10.1016/j.icarus.2019.04.018] [Journal Article/Letter]

2019. "Coronagraphic observations of the lunar sodium exosphere January–June, 2017." Icarus [10.1016/j.icarus.2019.02.027] [Journal Article/Letter]

2019. "Solar Wind Implantation Into the Lunar Regolith: Monte Carlo Simulations of H Retention in a Surface With Defects and the H 2 Exosphere." Journal of Geophysical Research: Planets 2018JE005805 [10.1029/2018je005805] [Journal Article/Letter]

2019. "Observations of Mercury's Exosphere: Composition and Structure." Mercury: The View After MESSENGER 371-406 [Article in Book]

2019. "Understanding Mercury's Exosphere: Models derived from MESSENGER observations." Mercury: The View After MESSENGER [Article in Book]

2018. "Extraterrestrial Meteors." Meteoroids: Sources of Meteors on Earth and Beyond [Article in Book]

2018. "Exospheric escape: A parametrical study." Advances in Space Research 62 (8): 2364-2371 [10.1016/j.asr.2017.06.015] [Journal Article/Letter]

2018. "Evidence Connecting Mercury's Magnesium Exosphere to Its Magnesium-Rich Surface Terrane." Geophysical Research Letters [10.1029/2018gl078407] [Journal Article/Letter]

2018. "The Dust, Atmosphere and Plasma at the Moon." New Views of the Moon 2 [Article in Book]

2017. "Contributions of solar wind and micrometeoroids to molecular hydrogen in the lunar exosphere." Icarus 283 31-37 [10.1016/j.icarus.2016.04.019] [Journal Article/Letter]

2017. "Seasonal variations of Mercury's magnesium dayside exosphere from MESSENGER observations." Icarus 281 46-54 [10.1016/j.icarus.2016.08.032] [Journal Article/Letter]

2016. "New discoveries from MESSENGER and insights into Mercury's exosphere." Geophysical Research Letters 43 (22): 11,545-11,551 [10.1002/2016gl071284] [Journal Article/Letter]

2016. "A cold-pole enhancement in Mercury's sodium exosphere." Geophysical Research Letters 43 (21): 11,121-11,128 [10.1002/2016gl071071] [Journal Article/Letter]

2016. "The gas-surface interaction of a human-occupied spacecraft with a near-Earth object." Advances in Space Research 58 (9): 1648-1653 [10.1016/j.asr.2016.08.031] [Journal Article/Letter]

2016. "Observations of the minor species Al and Fe in Mercury's exosphere." Icarus [10.1016/j.icarus.2016.10.019] [Journal Article/Letter]

2016. "Pathways for energization of Ca in Mercury’s exosphere." Icarus 268 32-36 [10.1016/j.icarus.2015.12.035] [Journal Article/Letter]

2015. "The meteoroid stream of comet Encke at Mercury: Implications for MErcury Surface, Space ENvironment, GEochemistry, and Ranging observations of the exosphere." Geophysical Research Letters 42 (18): 7311-7318 [10.1002/2015gl065361] [Journal Article/Letter]

2015. "Impact vaporization as a possible source of Mercury’s calcium exosphere." Icarus 250 230-237 [10.1016/j.icarus.2014.11.035] [Journal Article/Letter]

2015. "Mercury’s seasonal sodium exosphere: MESSENGER orbital observations." Icarus 248 547-559 [10.1016/j.icarus.2014.10.037] [Journal Article/Letter]

2014. "Seasonal variations in Mercury’s dayside calcium exosphere." Icarus 238 51-58 [10.1016/j.icarus.2014.04.049] [Journal Article/Letter]

2014. "Mercury’s Weather-Beaten Surface: Understanding Mercury in the Context of Lunar and Asteroidal Space Weathering Studies." Space Sci Rev 181 (1-4): 121-214 [10.1007/s11214-014-0039-5] [Journal Article/Letter]

2013. "Observation of neutral sodium above Mercury during the transit of November 8, 2006." Icarus 226 (1): 172-185 [10.1016/j.icarus.2013.05.029] [Journal Article/Letter]

2013. "The lunar photoelectron sheath: A change in trapping efficiency during a solar storm." Journal of Geophysical Research: Planets 118 (5): 1114-1122 [10.1002/jgre.20086] [Journal Article/Letter]

2012. "Modeling MESSENGER observations of calcium in Mercury's exosphere." Journal of Geophysical Research: Planets 117 (E12): [10.1029/2012je004158] [Journal Article/Letter]

2012. "MESSENGER observations of a flux-transfer-event shower at Mercury." Journal of Geophysical Research: Space Physics 117 (A12): [10.1029/2012ja017926] [Journal Article/Letter]

2012. "Metallic species, oxygen and silicon in the lunar exosphere: Upper limits and prospects for LADEE measurements." Journal of Geophysical Research 117 (A3): A03103 [10.1029/2011ja017044] [Journal Article/Letter]

2012. "Solar-Storm/Lunar Atmosphere Model (SSLAM): An overview of the effort and description of the driving storm environment." Journal of Geophysical Research 117 E00K04 [10.1029/2012je004070] [Journal Article/Letter]

2012. "The effect on the lunar exosphere of a coronal mass ejection passage." Journal of Geophysical Research 117 E00K02 [10.1029/2011je004011] [Journal Article/Letter]

2012. "Flux estimates of ions from the lunar exosphere." Geophysical Research Letters 39 13101 [10.1029/2012GL052001] [Journal Article/Letter]

2011. "Limits to Mercury's magnesium exosphere from MESSENGER second flyby observations." Planetary and Space Science 59 (15): 1992-2003 [10.1016/j.pss.2011.05.002] [Journal Article/Letter]

2011. "Regarding the possible generation of a lunar nightside exo-ionosphere." Icarus 216 (1): 169-172 [10.1016/j.icarus.2011.08.013] [Journal Article/Letter]

2011. ""Discharging of Roving Objects in the Lunar Polar Regions"." Journal of Spacecraft and Rockets 48 (4): 700-704 [10.2514/1.51897] [Journal Article/Letter]

2011. "Constraints on Mercury’s Na exosphere: Combined MESSENGER and ground-based data." Icarus 211 (1): 21-36 [10.1016/j.icarus.2010.10.019] [Journal Article/Letter]

2010. "Observations of the lunar impact plume from the LCROSS event." Geophysical Research Letters 37 (23): [10.1029/2010gl045508] [Journal Article/Letter]

2010. "Observations of metallic species in Mercury’s exosphere." Icarus 209 (1): 75-87 [10.1016/j.icarus.2010.02.018] [Journal Article/Letter]

2010. "Anticipated electrical environment within permanently shadowed lunar craters." Journal of Geophysical Research 115 (E3): E03004 [Full Text] [10.1029/2009JE003464] [Journal Article/Letter]

2010. "MESSENGER observations of large flux transfer events at Mercury." Geophysical Research Letters 37 (2): [10.1029/2009gl041485] [Journal Article/Letter]

2010. "Modeling of the magnetosphere of Mercury at the time of the first MESSENGER flyby ." Icarus 209 (1): 3-10 [Journal Article/Letter]

2009. "Sodium winds on Mercury." Icarus 204 (2): 355-367 [10.1016/j.icarus.2009.06.028] [Journal Article/Letter]

2009. "Sodium-ion pickup observed above the magnetopause during MESSENGER's first Mercury flyby: Constraints on neutral exospheric models." Geophysical Research Letters 36 (4): L04106 [10.1029/2008gl036207] [Journal Article/Letter]

2009. "Space environment of Mercury at the time of the first MESSENGER flyby: Solar wind and interplanetary magnetic field modeling of upstream conditions." Journal of Geophysical Research 114 (A10): A10101 [10.1029/2009ja014287] [Journal Article/Letter]

2009. "Mercury’s atmosphere and magnetosphere: MESSENGER third flyby observations (Invited)." AGU Fall Meeting Abstracts A1- [Journal Article/Letter]

2009. "MHD modeling of the interaction of the magnetosphere of Mercury with the solar wind during the MESSENGER flybys." AGU Fall Meeting Abstracts A8- [Journal Article/Letter]

2009. "Lunar Neutral Exosphere Properties from Pickup Ion Analysis." AGU Fall Meeting Abstracts 1266- [Journal Article/Letter]

2009. "Space Weathering Impact on Solar System Surfaces and Planetary Mission Science." AGU Fall Meeting Abstracts 1465- [Journal Article/Letter]

2008. "On the impact of multiply charged heavy solar wind ions on the surface of Mercury, the Moon and Ceres." Planetary and Space Science 56 (11): 1506-1516 [10.1016/j.pss.2008.07.018] [Journal Article/Letter]

2008. "MESSENGER Observations of the Composition of Mercury's Ionized Exosphere and Plasma Environment." Science 321 (5885): 90-92 [10.1126/science.1159314] [Journal Article/Letter]

2008. "Mercury's Magnetosphere After MESSENGER's First Flyby." Science 321 (5885): 85-89 [10.1126/science.1159040] [Journal Article/Letter]

2008. "Observations of the sodium tail of Mercury." Icarus 194 (1): 1-12 [10.1016/j.icarus.2007.09.023] [Journal Article/Letter]

2008. "Distribution of sodium pickup ions during MESSENGER's first and second Mercury flybys: constraints on exospheric models." AGU Fall Meeting Abstracts A43- [Journal Article/Letter]

2007. "Processes that Promote and Deplete the Exosphere of Mercury." Space Sci Rev 132 (2-4): 433-509 [10.1007/s11214-007-9232-0] [Journal Article/Letter]

2007. "Predicting the long-term solar wind ion-sputtering source at Mercury." Planetary and Space Science 55 (11): 1584-1595 [10.1016/j.pss.2006.10.011] [Journal Article/Letter]

2007. "Mercury’s Atmosphere: A Surface-Bounded Exosphere." Space Sci Rev 131 (1-4): 161-186 [10.1007/s11214-007-9260-9] [Journal Article/Letter]

2007. "Mercury's exosphere origins and relations to its magnetosphere and surface." Planetary and Space Science 55 (9): 1069-1092 [10.1016/j.pss.2006.11.008] [Journal Article/Letter]

2006. "Curve‐of‐Growth Model for Sodium D2 Emission at Mercury." Publications of the Astronomical Society of the Pacific 118 (847): 1344-1350 [10.1086/508070] [Journal Article/Letter]

2006. "Spatial distribution of sodium on Mercury." Icarus 181 (1): 1-12 [10.1016/j.icarus.2005.10.026] [Journal Article/Letter]

2006. "Measuring pickup ions to characterize the surfaces and exospheres of planetary bodies: Applications to the Moon." Geophysical Research Letters 33 (5): L05201 [10.1029/2005gl024520] [Journal Article/Letter]

2006. "Ice on the Moon and Mercury." Advances in Geosci 3 93-102 [Journal Article/Letter]

2005. "Origins of Europa Na cloud and torus." Icarus 178 (2): 367-385 [10.1016/j.icarus.2005.03.027] [Journal Article/Letter]

2001. "X-ray fluorescence measurements of the surface elemental composition of asteroid 433 Eros." Meteoritics and Planetary Science 36 1673-1695 [10.1111/j.1945-5100.2001.tb01856.x] [Journal Article/Letter]

1996. "Microwave Sounding of the Giant Planets." Icarus 119 (1): 67-89 [10.1006/icar.1996.0003] [Journal Article/Letter]


2019. "Mercury's Sodium Exosphere Dawn/Dusk Asymmetry." Proceedings of the American Geophysical Union Fall Meeting P13C-3527 [Proceedings]

2019. "Sputter Loss of an Early Transient Lunar Atmosphere." European Planetary Science Conference EPSC-DPS2019-70. [Proceedings]

2019. "Sodium exosphere of Mercury: A call for new Earth-based telescopes and observers." EPSC/ EPSC-DPS Joint Meeting 2019 13.1967 [Proceedings]

2019. "The Lunar Neon Exosphere seen in LACE Data." NASA Exploration Science Forum (AMES Research Center): [Proceedings]

2019. "Limits on X-Ray Luminosity from Pluto's H2 Corona." LPI/Pluto System After New Horizons 2133 id.7080 [Proceedings]

2019. "The Sun was likely a Slow Rotator: Lunar Geochemical Constraints." LPI (50.3050s): [Proceedings]

2019. "The Sun was likely a Slow Rotator: Lunar Geochemical Constraints." Lunar and Planetary Science Conference 50 [Proceedings]

2013. "'Where to Hide?': A Tele-Robotic Application for HEOMD's Earth-Moon L2 Mission." Lunar and Planetary Institute Science Conference Abstracts 44 2514 [Journal Article/Letter]

Selected Public Outreach

New Views of Mercury's Exosphere from MESSENGER

November 2018 - November Present

Public talk at the Geological Society of Wshington, Given at the COSMOS  Club, Washington, DC

October 24, 2018