Emil Lawrence Kepko

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Emil Lawrence Kepko

  • RESEARCH AST, FIELDS AND PARTICLES
  • 301.286.2728
  • NASA/GSFC
  • Mail Code: 674
  • Greenbelt , MD 20771
  • Employer: NASA
  • Brief Bio

    While at NASA/GSFC, I have been fortunate to work on a number of different projects with a variety of roles. My current science interests are focused on understanding pre-onset auroral signatures during magnetospheric substorms, and understanding the source of periodic density structures in the solar wind. In addition to my science interests, I have worked with AETD to develop capabilities on Center to enable highly reliable, highly capable cubesats that can be used either as inexpensive science platforms or could be used to create constellations of satellites. I have been involved in a number of LCAS and OCT proposals, and was Co-I on the ASTRE Heliophysics Explorer, which was selected for Phase A study, losing to eventual winner ICON (PI Tom Immel). I serve on both the Heliophysics and Cross-Cutting Technologies Lines of Business. Finally, I volunteer extensively for community service, including co-chairing the 2012/13 Heliophysics Roadmap, being Editor of JGR - Space Physics (through 2017), and serving on numerous review panels.

    Prior to coming to Goddard, I was worked at both UNH and Boston University. I received my Ph.D. in Geophysics and Space Physics from UCLA, with a thesis entitled, "Transient Convection in the Earth's Magnetosphere and the Generation of Pi2 Pulsations" (Advisor Margaret Kivelson). I was awarded the AGU Fred L. Scarf award, given annually to a recent Ph.D. recipient for outstanding dissertation research that contributes directly to solar-planetary science, in 2002.

    Research Interests

    Small satellites

    Working with both the Heliophysics Science Division (HSD) and the Applied Engineering Technology Directorate (AETD) I continue to push for high reliability and highly capable cubesats and small sats (<30 kg) that can be used to realize NASA's science objectives at a fraction of the cost of larger missions. Advancements in small satellite technologies will further enable constellations of 30+ spacecraft.

    Magnetospheric substorms

    Magnetospheric substorms are a fundamental process by which the magnetosphere processes energy it receives from the solar wind. I study many different aspects of substorms, ranging from Pi2 pulstions (T = 40-150s) that occur impulsively during substorms, to the cause of auroral signatures.

    Solar wind periodic density structures

    Surprisingly, the solar wind appears to contain highly periodic density structures, which in turn drive highly periodic magnetospheric pulsations. The source of these structures hs not been determined, but likely relate back to processes occurring near the solar surface.

    Positions/Employment

    2009 - Present

    Research Astrophysicist

    NASA Goddard Space Flight Center, Greenbelt, MD  
    2007 - 2009

    Research Scientist III

    University of New Hampshire Space Science Center, Durham, NH  
    2004 - 2007

    Senior Research Associate

    Boston University Center for Space Physics, Boston, MA  
    2001 - 2004

    Research Associate

    Boston University Center for Space Physics, Boston, MA  
    2004 - 2007

    Adjunct Professor

    Boston College Department of Geology and Geophysics, Chestnut Hill, MA Taught GE.150, "Introductory Astonomy" each fall semester while continuing full-time research at Boston University

    Education

     Ph.D. in Geophysics and Space Physics, University of California, Los Angeles, 2001
    "Transient convection in the Earth's magnetosphere and the generation of Pi2 pulsations"

    M.S. in Geophysics and Space Physics, University of California, Los Angeles, 1996

    B.S. in Astrophysics, University of California, Los Angeles, 1993

    Professional Service

    NASA
        Co-Chair of the 2012/2013 Heliophysics Roadmap
        Chair of the Geospace MOWG

    American Geophysical Union (AGU)
        Current Editor of JGR - Space Physics

    Goddard Space Flight Center
        Member of the GSFC Scientific Colloquium Committee
        Member of the Science Director's Council
        Member of the GSFC 2030 Science Vision Team

    Conferences and Workshops
        Currently serving 4-year term as lead organizer of IAGA Division.III, "Magnetospheric Phenomena"
        Current active member of the Geospace Environment Modeling (GEM) steering committee
        Co-organizer of the "Modes of magnetospheric response" focus group (completed 5 year term in 2013)
        IAGA 2011/2013/2015 Division III.2 Lead Convener (Magnetospheric substorms and tail physics)
        Program committee, Chapman Conference on "Fundamental Properties and Processes of Magnetotails"
        Program Committee, International Conference on Substorms -7 and -10
        Co-Convener, "Why does geomagentic activity vary with solar cycle?", special session at the 2011 AGU Fall meeting
        Co-Convener, "Modes of magnetospheric transport", special session at the 2008 Fall AGU meeting
        Co-Convener, "ST13: The relationship between global ULF wave modes, plasma gradients and auroral acceleration processes", 2003 joing AGU-EGS meeting.

    Other
        External committee member for Ph.D student Matthew Gilson, University of New Hampshire (Joachim Raeder, advisor). Thesis entitled, “Global structure of the nightside proton precipitation during substorms using simulations and observations.” Defended November, 2011.
        External committee member for Ph.D. student Emma Spanswick, University of Calgary (Eric Donovan, advisor). Thesis entitled, “Global Evolution of Substorm Electron Injections.” Defended January, 2009.


        

    Selected Publications

    Refereed

    Le, G., H. Lühr, B. J. Anderson, et al. R. J. Strangeway, C. T. Russell, H. Singer, J. A. Slavin, Y. Zhang, T. Huang, K. Bromund, P. J. Chi, G. Lu, D. Fischer, E. L. Kepko, H. K. Leinweber, W. Magnes, R. Nakamura, F. Plaschke, J. Park, J. Rauberg, C. Stolle, and R. B. Torbert. 2016. "Magnetopause erosion during the March 17, 2015, magnetic storm: Combined field-aligned currents, auroral oval, and magnetopause observations." Geophysical Research Letters, 43 (6): 2396–2404 [10.1002/2016gl068257]

    Kepko, L., N. Viall, S. K. Antiochos, et al. S. T. Lepri, J. C. Kasper, and M. Weberg. 2016. "Implications of L1 observations for slow solar wind formation by solar reconnection." Geophysical Research Letters, 43 (9): 4089–4097 [10.1002/2016gl068607]

    Kepko, E. L., J. Slavin, K.-H. Glassmeier, and T. Sundberg. 2014. "The substorm current wedge at Earth and Mercury." AGU Monograph, "Magnetotails in the Solar System",

    Kepko, L., E. Spanswick, E. Donovan, and V. Angelopoulos. 2013. "Preonset white light and redline streamers: Do they represent different onset scenarios?" AGU Fall Meeting Abstracts,

    Sobel, E. I., L. Kepko, V. Angelopoulos, E. Donovan, and E. Spanswick. 2013. "The Search for Precursor Redline Auroral Events." AGU Fall Meeting Abstracts, 2190-:

    Kissinger, J., L. Kepko, D. N. Baker, et al. S. G. Kanekal, W. Li, R. L. McPherron, and V. Angelopoulos. 2013. "Particle Energization During Magnetic Storms with Steady Magnetospheric Convection." AGU Fall Meeting Abstracts, 2183-:

    Moore, T. E., C. R. Chappell, J. H. Clemmons, et al. C. M. Cully, E. Donovan, G. D. Earle, R. A. Heelis, L. M. Kistler, L. Kepko, G. V. Khazanov, D. J. Knudsen, M. Lessard, J. P. McFadden, M. J. Nicolls, C. J. Pollock, R. F. Pfaff, R. Rankin, D. E. Rowland, J. L. Semeter, J. P. Thayer, and R. Winglee. 2013. "MEMEX: Mechanisms of Energetic Mass Ejection Explorer." AGU Fall Meeting Abstracts, A6-:

    Kissinger, J., F. Wilder, R. L. McPherron, et al. T. S. Hsu, J. Bake, and E. L. Kepko. 2013. "Statistical occurrence and dynamics of the Harang discontinuity during steady magnetospheric convection." J. Geophys. Res., [10.1002/jgra.50503]

    Simoes, F., R. F. Pfaff, H. T. Freudenreich, et al. J. H. Klenzing, D. E. Rowland, K. Bromund, E. L. Kepko, G. Le, M. C. Liebrecht, S. C. Martin, and P. Uribe. 2013. "Equatorial ionosphere semiannual oscillation investigated from Schumann resonance measurements on board the C/NOFS satellite." Journal of Geophysical Research (Atmospheres), 118: 12,045-12,051 [10.1002/jgrd.50797]

    Gilson, M. L., J. Raeder, E. Donovan, Y. S. Ge, and L. Kepko. 2012. "Global simulation of proton precipitation due to field line curvature during substorms." Journal of Geophysical Research (Space Physics), 117: [5216-10.1029/2012JA017562]

    Keiling, A., K. Shiokawa, V. Uritsky, et al. V. Sergeev, E. Zesta, E. L. Kepko, and N. Østgaard. 2012. "Auroral Signatures of the Dynamic Plasma Sheet, in Auroral Signatures of the Dynamic Plasma Sheet." AGU Monograph, "Auroral Phenomenology and Magnetospheric Processes: Earth And Other Planets", [10.1029/2012GM001231]

    Gilson, M., J. Raeder, E. Donovan, Y. S. Ge, and E. L. Kepko. 2012. "Global simulation of protoon precipitation due to field line curvature during substorms." J. Geophys. Res., [10.1029/2012JA017562]

    Frisell, N., J. Baker, J. Ruohoniemi, et al. L. Clausen, Z. Kale, I. Rae, E. L. Kepko, K. Oksavik, R. Greenwald, and M. West. 2011. "First radar observations in the vicinity of the plasmapause of pulsed ionospheric ionospheric flows generated by bursty bulk flows." Geophys Res. Lett., 38:

    Kepko, E. L., E. Spanswick, V. Angelopoulos, et al. E. Donovan, J. McFadden, K.-H. Glassmeier, J. Raeder, and H. J. Singer. 2010. "Equatorward moving auroral signatures of a flow burst observed prior to auroral onset." Geophys. Res. Lett.,

    Kepko, L., E. Spanswick, V. Angelopoulos, et al. E. Donovan, J. McFadden, K.-H. Glassmeier, J. Raeder, and H. J. Singer. 2009. "Equatorward moving auroral signatures of a flow burst observed prior to auroral onset." Geophysical Research Letters, 36: [24104-10.1029/2009GL041476]

    Kepko, E. L., H. E. Spence, and D. F. Smart. 2009. "Solar cosmic ray events observed in Greenland ice cores: 1940-1950." Advances in Space Research,

    Kepko, E. L., H. E. Spence, D. F. Smart, and M. A. Shea. 2009. "Interhemispheric observations of impulsive nitrate enhancements associated with the four large ground-level solar cosmic ray events (1940-1950)." Journal of Atmospheric and Solar-Terrestrial Physics, [10.1016/j.jastp.2009.07.002]

    Viall-Kepko, N. M., E. L. Kepko, and H. E. Spence. 2009. "Relative occurrence rates and connection of discrete frequency oscillations in the solar wind density and dayside magnetosphere." J. Geophys. Res., 114 (A01201): [10.1029/2008JA013334]

    Viall, N. M., L. Kepko, and H. E. Spence. 2008. "Inherent length-scales of periodic solar wind number density structures." Journal of Geophysical Research (Space Physics), 113: [7101 10.1029/2007JA012881]

    Kepko, L., J. Raeder, V. Angelopoulos, et al. J. McFadden, D. Larson, H. U. Auster, W. Magnes, H. U. Frey, C. Carlson, M. Henderson, S. B. Mende, K. Yumoto, H. J. Singer, G. Parks, I. Mann, C. T. Russell, E. Donovan, and R. McPherron. 2008. "Highly periodic stormtime activations observed by THEMIS prior to substorm onset." Geophysical Research Letters, 35: [17-10.1029/2008GL034235]

    Gabrielse, C., V. Angelopoulos, A. Runov, et al. L. Kepko, K. H. Glassmeier, H. U. Auster, J. McFadden, C. W. Carlson, and D. Larson. 2008. "Propagation characteristics of plasma sheet oscillations during a small storm." Geophysical Research Letters, 35: [17-10.1029/2008GL033664]

    McPherron, R. L., V. Angelopolous, P. Chi, et al. K. Glassmeier, L. Kepko, C. T. Russell, D. Larsen, I. Mann, J. McFadden, S. Mende, and H. Singer. 2008. "Disruption of the inner edge of the tail current by earthward flow bursts." AGU Spring Meeting Abstracts, 4-:

    Angelopoulos, V., D. Larson, J. P. McFadden, et al. C. W. Carlson, K. Glassmeier, S. Mende, C. T. Russell, A. Runov, X. Zhou, and L. Kepko. 2008. "THEMIS observations of tail reconnection around the times of substorm onset." AGU Spring Meeting Abstracts, A6-:

    Kepko, L., J. Raeder, V. Angelopoulos, et al. C. W. Carlson, K. Glassmeier, S. Mende, J. L. McFadden, H. Singer, G. Parks, M. Fillingim, I. Mann, E. Donovan, and C. T. Russell. 2008. "THEMIS Observations of Current Sheet Flapping." AGU Fall Meeting Abstracts, 1708-:

    Raeder, J., L. Kepko, A. Vapirev, et al. M. Fok, B. Hu, F. Toffoletto, and D. Larson. 2008. "Substorm Dynamics: THEMIS Data and OpenGGCM Simulations." AGU Fall Meeting Abstracts, 5-:

    Angelopoulos, V., J. McFadden, D. Larson, et al. C. Carlson, S. Mende, H. Frey, T. Phan, D. Sibeck, K. Glassmeier, U. Auster, E. Donovan, I. Mann, J. Rae, C. Russell, A. Runov, X. Zhou, and L. Kepko. 2008. "Tail Reconnection Triggering Substorm Onset." AGU Fall Meeting Abstracts, 3-:

    Baker, J. B., J. M. Ruohoniemi, N. A. Frissell, et al. R. A. Greenwald, I. J. Rae, Z. C. Kale, L. Kepko, M. Lester, A. Grocott, T. K. Yeoman, and S. E. Milan. 2008. "SuperDARN Observations of Pi2 Electric Field Pulsations during THEMIS Substorms." AGU Fall Meeting Abstracts, A1688-:

    Kepko, E. L., H. E. Spence, M. A. Shea, D. F. Smart, and G. Dreschoff. 2008. "Observations of Impulsive Nitrate Enhancements Associated With Ground-Level Cosmic Ray Events 1-4 (1942-1949)." in Proceedings of the 30th International Cosmic Ray Conference,

    Viall-Kepko, N. M., E. L. Kepko, and H. E. Spence. 2008. "Inherent length-scales of periodic solar wind number density structures." J. Geophys. Res., 113 (A07101): [10.1029/2007JA012881]

    Raeder, J., L. Kepko, E. Kaghashvili, et al. V. Angelopoulos, D. Larson, J. McFadden, C. Carlson, K. Glassmeier, U. Auster, and G. Parks. 2007. "OpenGGCM Simulation of the March 23, 2007 Substorm Observed by THEMIS." AGU Fall Meeting Abstracts, 8-:

    Kaghashvili, E., J. Raeder, L. Kepko, and D. Larson. 2007. "Solar wind ULF wave frequency dependence of the ionospheric response." AGU Fall Meeting Abstracts, A1073-:

    Gabrielse, C., V. Angelopoulos, A. Runov, et al. L. Kepko, K. H. Glassmeier, U. Auster, J. McFadden, C. W. Carlson, D. Larson, T. Phan, and J. Eastwood. 2007. "Propagation Characteristics of Plasma Sheet Oscillations During a Small Storm." AGU Fall Meeting Abstracts, A1176-:

    Kepko, L., J. Raeder, V. Angelopoulos, et al. C. Carlson, H. Frey, D. Larson, J. McFadden, S. Mende, G. Parks, K. Glassmeier, U. Auster, E. Donovan, C. Russell, Y. Ge, I. Mann, M. Henderson, K. Yumoto, and H. Singer. 2007. "Highly periodic activations observed by THEMIS prior to substorm onset." AGU Fall Meeting Abstracts, 5-:

    Spence, H., A. N. Robison, L. Kepko, et al. S. Petrinec, S. Fuselier, and S. Claflin. 2006. "Solar Wind and IMF Control of Southern Hemisphere Cusp Aurora Location." AGU Spring Meeting Abstracts, A9-:

    Kepko, L., H. E. Spence, M. A. Shea, et al. D. F. Smart, M. Curran, and G. A. Dreschhoff. 2006. "Inter-hemispheric comparisons of SPE-associated Impulsive Nitrate Enhancements in Polar Ice." AGU Spring Meeting Abstracts, 9-:

    Kasper, J. C., H. Spence, J. B. Blake, et al. M. Golightly, L. Kepko, J. Mazur, T. Onsager, and L. Townsend. 2006. "Characterizing the evolution of radiation with the Cosmic Ray Telescope for the Effects of Radiation." 36th COSPAR Scientific Assembly, 36: 3480-.

    Kasper, J. C., H. Spence, J. B. Blake, et al. M. Golightly, L. Kepko, J. Mazur, T. Onsager, and L. Townsend. 2006. "CRaTER: the Cosmic Ray Telescope for the Effects of Radiation experiment on Lunar Reconnaissance Orbiter." 36th COSPAR Scientific Assembly, 36: 3381-.

    Smart, D. F., M. A. Shea, H. E. Spence, and L. Kepko. 2006. "Two groups of extremely large >30 MeV solar proton fluence events." Advances in Space Research, 37: 1734-1740 [10.1016/j.asr.2005.09.008]

    Viall, N. M., L. Kepko, and H. Spence. 2006. "Discrete Frequency Magnetospheric Oscillations and Their Relation to Periodic Solar Wind Number Density Structures." AGU Spring Meeting Abstracts, A2-:

    Kepko, L., N. M. Viall, and H. E. Spence. 2006. "Shock and discontinuity associated periodicities in the solar wind and magnetosphere." AGU Fall Meeting Abstracts, A378-:

    Viall, N. M., L. Kepko, and H. Spence. 2006. "Magnetospheric Oscillations and Their Relation to Periodic Multiple Discrete Solar Wind Number Density Variations." AGU Fall Meeting Abstracts, A384-:

    Lin, T., H. Spence, S. P. Gary, T. Mukai, and L. Kepko. 2005. "Mean of Proton Temperature Anisotropy in the Solar Wind is Solely Controlled by the Threshold of its Excited Instabilities and its Implication: Two Years of Geotail Observations." AGU Fall Meeting Abstracts, A1252-:

    Viall, N. M., L. Kepko, and H. Spence. 2005. "The Occurrence Rate of Solar Wind Periodic Number Density Structures." AGU Fall Meeting Abstracts, 264-:

    Guild, T., H. Spence, J. Lyon, et al. C. Goodrich, V. Merkin, and L. Kepko. 2005. "Embedding a Hall MHD plasma sheet simulation inside the Lyon-Fedder-Mobarry global MHD model." AGU Fall Meeting Abstracts, A326-:

    Kepko, L., M. G. Kivelson, R. L. McPherron, and H. E. Spence. 2004. "Relative timing of substorm onset phenomena." Journal of Geophysical Research (Space Physics), 109: [4203-10.1029/2003JA010285]

    Smart, D. F., M. A. Shea, H. E. Spence, and L. Kepko. 2004. "The Extremes in the Interplanetary Solar Proton Environment and the Two Classes of Solar Events Associated with Very Large > 30 MeV Solar Proton Fluence Events." 35th COSPAR Scientific Assembly, 35: 3266-.

    Merkin, V., C. Goodrich, J. Lyon, et al. M. Wiltberger, W. Wang, and L. Kepko. 2004. "Investigation of Sawtooth activity duing the Halloween Storms of 2003." AGU Fall Meeting Abstracts, 7-:

    Guild, T., H. Spence, C. Goodrich, J. Lyon, and L. Kepko. 2004. "A Statistical Comparison of the Geotail and MHD Plasma Sheet." AGU Fall Meeting Abstracts, A1179-:

    Lin, T., H. Spence, L. Kepko, S. P. Gary, and T. Mukai. 2004. "Temperature Anisotropy Constraint In The Plasma Sheet." AGU Fall Meeting Abstracts, A1166-:

    Spence, H. E., L. Kepko, M. A. Shea, and D. F. Smart. 2004. "Comparison of Solar Energetic Particle Events and Impulsive Nitrate Increases in Greenland Ice Cores." AGU Fall Meeting Abstracts, 313-:

    Kepko, L., and H. E. Spence. 2004. "Preliminary Results of Nitrate Analysis of Greenland Ice Cores." AGU Fall Meeting Abstracts, A1146-:

    Goodrich, C., J. Lyon, M. Wiltberger, W. Wang, and L. Kepko. 2004. "Numerical Simulations of the October-November 2003 Super Storms." AGU Fall Meeting Abstracts, A2-:

    Huang, C., H. Spence, L. Kepko, et al. J. Lyon, C. Goodrich, T. Guild, M. Wiltberger, J. Hughes, and H. Singer. 2003. "Comparison of LFM Simulation With Tsyganenko Models and GOES Observations." AGU Fall Meeting Abstracts, A569-:

    Spence, H., J. Lyon, L. Kepko, T. Guild, and M. Wiltberger. 2003. "Coupling of Solar Wind Energy to the Magnetosphere via ULF Waves." AGU Fall Meeting Abstracts, 1-:

    Guild, T., H. Spence, L. Kepko, et al. M. Wiltberger, J. Lyon, C. Goodrich, C. Huang, H. Petschek, J. Hughes, T. Mukai, and S. Kokubun. 2003. "A Statistical Study of Plasma Sheet Parameters in Geotail Data and the LFM MHD Model." AGU Fall Meeting Abstracts, 200-:

    Kepko, L., and H. E. Spence. 2003. "Observations of discrete, global magnetospheric oscillations directly driven by solar wind density variations." Journal of Geophysical Research (Space Physics), 108: [1257-10.1029/2002JA009676]

    Kepko, L., H. E. Spence, and H. J. Singer. 2002. "ULF waves in the solar wind as direct drivers of magnetospheric pulsations." Geophysical Research Letters, 29: [1197-10.1029/2001GL014405]

    Kepko, L., and H. E. Spence. 2002. "Forced Breathing of the Magnetosphere by Solar Wind Dynamic Pressure Variations." AGU Spring Meeting Abstracts, 8-:

    Spence, H. E., L. Kepko, H. Petschek, et al. T. Guild, E. Huang, S. Lamassa, and S. McCurdy. 2002. "Do Shocks Excite Global Cavity Mode Oscillations?" AGU Spring Meeting Abstracts, 9-:

    McCurdy, S., H. E. Spence, and L. Kepko. 2002. "Characterizing the Periodicity of Bursty Bulk Flows." AGU Fall Meeting Abstracts, 2-:

    Spence, H. E., and L. Kepko. 2001. "On the Characteristics of Plasma Sheet Dynamics." AGU Spring Meeting Abstracts, 62-:

    Kepko, L., M. G. Kivelson, and K. Yumoto. 2001. "Flow bursts, braking, and Pi2 pulsations." Journal of Geophysical Research, 106: 1903-1916 [10.1029/2000JA000158]

    Elphic, R. C., J. D. Means, R. C. Snare, et al. R. J. Strangeway, L. Kepko, and R. E. Ergun. 2001. "Magnetic Field Instruments for the Fast Auroral Snapshot Explorer." Space Science Reviews, 98: 151-168.

    Henderson, M. G., L. Kepko, H. E. Spence, et al. M. Connors, J. B. Sigwarth, L. A. Frank, and H. J. Singer. 2001. "The evolution of north-south aligned auroral forms into auroral torch structures: The generation of omega bands and Ps6 pulsations via flow bursts." AGU Fall Meeting Abstracts, 809-:

    Kepko, L., and H. E. Spence. 2001. "Periodicity in the Solar Wind as a Source of ULF Pulsations." AGU Fall Meeting Abstracts, A789-:

    Spence, H. E., L. Kepko, T. Guild, and E. Huang. 2001. "Post-shock ULF Wave Activity Driven by Dynamic Pressure Variations." AGU Fall Meeting Abstracts, 9-:

    Kepko, L., and R. L. McPherron. 2001. "Comment on “Evaluation of low-latitude Pi2 pulsations as indicators of substorm onset using Polar ultraviolet imagery” by K. Liou, et al.." J. Geophys. Res., 106 (A9): 18919-18922 [10.1029/2000JA000189]

    Strangeway, R. J., L. Kepko, R. C. Elphic, et al. C. W. Carlson, R. E. Ergun, J. P. McFadden, W. J. Peria, G. T. Delory, C. C. Chaston, M. Temerin, C. A. Cattell, E. Mobius, L. M. Kistler, D. M. Klumpar, W. K. Peterson, E. G. Shelley, and R. F. Pfaff. 1998. "FAST observations of VLF waves in the auroral zone: Evidence of very low plasma densities." Geophysical Research Letters, 25: 2065-2068 [10.1029/98GL00664]

    Elphic, R. C., J. W. Bonnell, R. J. Strangeway, et al. L. Kepko, R. E. Ergun, J. P. McFadden, C. W. Carlson, W. Peria, C. A. Cattell, D. Klumpar, E. Shelley, W. Peterson, E. Moebius, L. Kistler, and R. Pfaff. 1998. "The auroral current circuit and field-aligned currents observed by FAST." Geophysical Research Letters, 25: 2033-2036 [10.1029/98GL01158]

    Kivelson, M. G., K. K. Khurana, R. J. Walker, L. Kepko, and D. Xu. 1996. "Flux ropes, interhemispheric conjugacy, and magnetospheric current closure." Journal of Geophysical Research, 101: 27341-27350 [10.1029/96JA02220]

    Brief Bio

    While at NASA/GSFC, I have been fortunate to work on a number of different projects with a variety of roles. My current science interests are focused on understanding pre-onset auroral signatures during magnetospheric substorms, and understanding the source of periodic density structures in the solar wind. In addition to my science interests, I have worked with AETD to develop capabilities on Center to enable highly reliable, highly capable cubesats that can be used either as inexpensive science platforms or could be used to create constellations of satellites. I have been involved in a number of LCAS and OCT proposals, and was Co-I on the ASTRE Heliophysics Explorer, which was selected for Phase A study, losing to eventual winner ICON (PI Tom Immel). I serve on both the Heliophysics and Cross-Cutting Technologies Lines of Business. Finally, I volunteer extensively for community service, including co-chairing the 2012/13 Heliophysics Roadmap, being Editor of JGR - Space Physics (through 2017), and serving on numerous review panels.

    Prior to coming to Goddard, I was worked at both UNH and Boston University. I received my Ph.D. in Geophysics and Space Physics from UCLA, with a thesis entitled, "Transient Convection in the Earth's Magnetosphere and the Generation of Pi2 Pulsations" (Advisor Margaret Kivelson). I was awarded the AGU Fred L. Scarf award, given annually to a recent Ph.D. recipient for outstanding dissertation research that contributes directly to solar-planetary science, in 2002.

    Selected Publications

    Refereed

    Le, G., H. Lühr, B. J. Anderson, et al. R. J. Strangeway, C. T. Russell, H. Singer, J. A. Slavin, Y. Zhang, T. Huang, K. Bromund, P. J. Chi, G. Lu, D. Fischer, E. L. Kepko, H. K. Leinweber, W. Magnes, R. Nakamura, F. Plaschke, J. Park, J. Rauberg, C. Stolle, and R. B. Torbert. 2016. "Magnetopause erosion during the March 17, 2015, magnetic storm: Combined field-aligned currents, auroral oval, and magnetopause observations." Geophysical Research Letters 43 (6): 2396–2404 [10.1002/2016gl068257]

    Kepko, L., N. Viall, S. K. Antiochos, et al. S. T. Lepri, J. C. Kasper, and M. Weberg. 2016. "Implications of L1 observations for slow solar wind formation by solar reconnection." Geophysical Research Letters 43 (9): 4089–4097 [10.1002/2016gl068607]

    Kepko, E. L., J. Slavin, K.-H. Glassmeier, and T. Sundberg. 2014. "The substorm current wedge at Earth and Mercury." AGU Monograph, "Magnetotails in the Solar System"

    Kepko, L., E. Spanswick, E. Donovan, and V. Angelopoulos. 2013. "Preonset white light and redline streamers: Do they represent different onset scenarios?" AGU Fall Meeting Abstracts

    Sobel, E. I., L. Kepko, V. Angelopoulos, E. Donovan, and E. Spanswick. 2013. "The Search for Precursor Redline Auroral Events." AGU Fall Meeting Abstracts 2190-

    Kissinger, J., L. Kepko, D. N. Baker, et al. S. G. Kanekal, W. Li, R. L. McPherron, and V. Angelopoulos. 2013. "Particle Energization During Magnetic Storms with Steady Magnetospheric Convection." AGU Fall Meeting Abstracts 2183-

    Moore, T. E., C. R. Chappell, J. H. Clemmons, et al. C. M. Cully, E. Donovan, G. D. Earle, R. A. Heelis, L. M. Kistler, L. Kepko, G. V. Khazanov, D. J. Knudsen, M. Lessard, J. P. McFadden, M. J. Nicolls, C. J. Pollock, R. F. Pfaff, R. Rankin, D. E. Rowland, J. L. Semeter, J. P. Thayer, and R. Winglee. 2013. "MEMEX: Mechanisms of Energetic Mass Ejection Explorer." AGU Fall Meeting Abstracts A6-

    Kissinger, J., F. Wilder, R. L. McPherron, et al. T. S. Hsu, J. Bake, and E. L. Kepko. 2013. "Statistical occurrence and dynamics of the Harang discontinuity during steady magnetospheric convection." J. Geophys. Res. [10.1002/jgra.50503]

    Simoes, F., R. F. Pfaff, H. T. Freudenreich, et al. J. H. Klenzing, D. E. Rowland, K. Bromund, E. L. Kepko, G. Le, M. C. Liebrecht, S. C. Martin, and P. Uribe. 2013. "Equatorial ionosphere semiannual oscillation investigated from Schumann resonance measurements on board the C/NOFS satellite." Journal of Geophysical Research (Atmospheres) 118 12,045-12,051 [10.1002/jgrd.50797]

    Gilson, M. L., J. Raeder, E. Donovan, Y. S. Ge, and L. Kepko. 2012. "Global simulation of proton precipitation due to field line curvature during substorms." Journal of Geophysical Research (Space Physics) 117 [5216-10.1029/2012JA017562]

    Keiling, A., K. Shiokawa, V. Uritsky, et al. V. Sergeev, E. Zesta, E. L. Kepko, and N. Østgaard. 2012. "Auroral Signatures of the Dynamic Plasma Sheet, in Auroral Signatures of the Dynamic Plasma Sheet." AGU Monograph, "Auroral Phenomenology and Magnetospheric Processes: Earth And Other Planets" [10.1029/2012GM001231]

    Gilson, M., J. Raeder, E. Donovan, Y. S. Ge, and E. L. Kepko. 2012. "Global simulation of protoon precipitation due to field line curvature during substorms." J. Geophys. Res. [10.1029/2012JA017562]

    Frisell, N., J. Baker, J. Ruohoniemi, et al. L. Clausen, Z. Kale, I. Rae, E. L. Kepko, K. Oksavik, R. Greenwald, and M. West. 2011. "First radar observations in the vicinity of the plasmapause of pulsed ionospheric ionospheric flows generated by bursty bulk flows." Geophys Res. Lett. 38

    Kepko, E. L., E. Spanswick, V. Angelopoulos, et al. E. Donovan, J. McFadden, K.-H. Glassmeier, J. Raeder, and H. J. Singer. 2010. "Equatorward moving auroral signatures of a flow burst observed prior to auroral onset." Geophys. Res. Lett.

    Kepko, L., E. Spanswick, V. Angelopoulos, et al. E. Donovan, J. McFadden, K.-H. Glassmeier, J. Raeder, and H. J. Singer. 2009. "Equatorward moving auroral signatures of a flow burst observed prior to auroral onset." Geophysical Research Letters 36 [24104-10.1029/2009GL041476]

    Kepko, E. L., H. E. Spence, and D. F. Smart. 2009. "Solar cosmic ray events observed in Greenland ice cores: 1940-1950." Advances in Space Research

    Kepko, E. L., H. E. Spence, D. F. Smart, and M. A. Shea. 2009. "Interhemispheric observations of impulsive nitrate enhancements associated with the four large ground-level solar cosmic ray events (1940-1950)." Journal of Atmospheric and Solar-Terrestrial Physics [10.1016/j.jastp.2009.07.002]

    Viall-Kepko, N. M., E. L. Kepko, and H. E. Spence. 2009. "Relative occurrence rates and connection of discrete frequency oscillations in the solar wind density and dayside magnetosphere." J. Geophys. Res. 114 (A01201): [10.1029/2008JA013334]

    Viall, N. M., L. Kepko, and H. E. Spence. 2008. "Inherent length-scales of periodic solar wind number density structures." Journal of Geophysical Research (Space Physics) 113 [7101 10.1029/2007JA012881]

    Kepko, L., J. Raeder, V. Angelopoulos, et al. J. McFadden, D. Larson, H. U. Auster, W. Magnes, H. U. Frey, C. Carlson, M. Henderson, S. B. Mende, K. Yumoto, H. J. Singer, G. Parks, I. Mann, C. T. Russell, E. Donovan, and R. McPherron. 2008. "Highly periodic stormtime activations observed by THEMIS prior to substorm onset." Geophysical Research Letters 35 [17-10.1029/2008GL034235]

    Gabrielse, C., V. Angelopoulos, A. Runov, et al. L. Kepko, K. H. Glassmeier, H. U. Auster, J. McFadden, C. W. Carlson, and D. Larson. 2008. "Propagation characteristics of plasma sheet oscillations during a small storm." Geophysical Research Letters 35 [17-10.1029/2008GL033664]

    McPherron, R. L., V. Angelopolous, P. Chi, et al. K. Glassmeier, L. Kepko, C. T. Russell, D. Larsen, I. Mann, J. McFadden, S. Mende, and H. Singer. 2008. "Disruption of the inner edge of the tail current by earthward flow bursts." AGU Spring Meeting Abstracts 4-

    Angelopoulos, V., D. Larson, J. P. McFadden, et al. C. W. Carlson, K. Glassmeier, S. Mende, C. T. Russell, A. Runov, X. Zhou, and L. Kepko. 2008. "THEMIS observations of tail reconnection around the times of substorm onset." AGU Spring Meeting Abstracts A6-

    Kepko, L., J. Raeder, V. Angelopoulos, et al. C. W. Carlson, K. Glassmeier, S. Mende, J. L. McFadden, H. Singer, G. Parks, M. Fillingim, I. Mann, E. Donovan, and C. T. Russell. 2008. "THEMIS Observations of Current Sheet Flapping." AGU Fall Meeting Abstracts 1708-

    Raeder, J., L. Kepko, A. Vapirev, et al. M. Fok, B. Hu, F. Toffoletto, and D. Larson. 2008. "Substorm Dynamics: THEMIS Data and OpenGGCM Simulations." AGU Fall Meeting Abstracts 5-

    Angelopoulos, V., J. McFadden, D. Larson, et al. C. Carlson, S. Mende, H. Frey, T. Phan, D. Sibeck, K. Glassmeier, U. Auster, E. Donovan, I. Mann, J. Rae, C. Russell, A. Runov, X. Zhou, and L. Kepko. 2008. "Tail Reconnection Triggering Substorm Onset." AGU Fall Meeting Abstracts 3-

    Baker, J. B., J. M. Ruohoniemi, N. A. Frissell, et al. R. A. Greenwald, I. J. Rae, Z. C. Kale, L. Kepko, M. Lester, A. Grocott, T. K. Yeoman, and S. E. Milan. 2008. "SuperDARN Observations of Pi2 Electric Field Pulsations during THEMIS Substorms." AGU Fall Meeting Abstracts A1688-

    Kepko, E. L., H. E. Spence, M. A. Shea, D. F. Smart, and G. Dreschoff. 2008. "Observations of Impulsive Nitrate Enhancements Associated With Ground-Level Cosmic Ray Events 1-4 (1942-1949)." in Proceedings of the 30th International Cosmic Ray Conference

    Viall-Kepko, N. M., E. L. Kepko, and H. E. Spence. 2008. "Inherent length-scales of periodic solar wind number density structures." J. Geophys. Res. 113 (A07101): [10.1029/2007JA012881]

    Raeder, J., L. Kepko, E. Kaghashvili, et al. V. Angelopoulos, D. Larson, J. McFadden, C. Carlson, K. Glassmeier, U. Auster, and G. Parks. 2007. "OpenGGCM Simulation of the March 23, 2007 Substorm Observed by THEMIS." AGU Fall Meeting Abstracts 8-

    Kaghashvili, E., J. Raeder, L. Kepko, and D. Larson. 2007. "Solar wind ULF wave frequency dependence of the ionospheric response." AGU Fall Meeting Abstracts A1073-

    Gabrielse, C., V. Angelopoulos, A. Runov, et al. L. Kepko, K. H. Glassmeier, U. Auster, J. McFadden, C. W. Carlson, D. Larson, T. Phan, and J. Eastwood. 2007. "Propagation Characteristics of Plasma Sheet Oscillations During a Small Storm." AGU Fall Meeting Abstracts A1176-

    Kepko, L., J. Raeder, V. Angelopoulos, et al. C. Carlson, H. Frey, D. Larson, J. McFadden, S. Mende, G. Parks, K. Glassmeier, U. Auster, E. Donovan, C. Russell, Y. Ge, I. Mann, M. Henderson, K. Yumoto, and H. Singer. 2007. "Highly periodic activations observed by THEMIS prior to substorm onset." AGU Fall Meeting Abstracts 5-

    Spence, H., A. N. Robison, L. Kepko, et al. S. Petrinec, S. Fuselier, and S. Claflin. 2006. "Solar Wind and IMF Control of Southern Hemisphere Cusp Aurora Location." AGU Spring Meeting Abstracts A9-

    Kepko, L., H. E. Spence, M. A. Shea, et al. D. F. Smart, M. Curran, and G. A. Dreschhoff. 2006. "Inter-hemispheric comparisons of SPE-associated Impulsive Nitrate Enhancements in Polar Ice." AGU Spring Meeting Abstracts 9-

    Kasper, J. C., H. Spence, J. B. Blake, et al. M. Golightly, L. Kepko, J. Mazur, T. Onsager, and L. Townsend. 2006. "Characterizing the evolution of radiation with the Cosmic Ray Telescope for the Effects of Radiation." 36th COSPAR Scientific Assembly 36 3480-

    Kasper, J. C., H. Spence, J. B. Blake, et al. M. Golightly, L. Kepko, J. Mazur, T. Onsager, and L. Townsend. 2006. "CRaTER: the Cosmic Ray Telescope for the Effects of Radiation experiment on Lunar Reconnaissance Orbiter." 36th COSPAR Scientific Assembly 36 3381-

    Smart, D. F., M. A. Shea, H. E. Spence, and L. Kepko. 2006. "Two groups of extremely large >30 MeV solar proton fluence events." Advances in Space Research 37 1734-1740 [10.1016/j.asr.2005.09.008]

    Viall, N. M., L. Kepko, and H. Spence. 2006. "Discrete Frequency Magnetospheric Oscillations and Their Relation to Periodic Solar Wind Number Density Structures." AGU Spring Meeting Abstracts A2-

    Kepko, L., N. M. Viall, and H. E. Spence. 2006. "Shock and discontinuity associated periodicities in the solar wind and magnetosphere." AGU Fall Meeting Abstracts A378-

    Viall, N. M., L. Kepko, and H. Spence. 2006. "Magnetospheric Oscillations and Their Relation to Periodic Multiple Discrete Solar Wind Number Density Variations." AGU Fall Meeting Abstracts A384-

    Lin, T., H. Spence, S. P. Gary, T. Mukai, and L. Kepko. 2005. "Mean of Proton Temperature Anisotropy in the Solar Wind is Solely Controlled by the Threshold of its Excited Instabilities and its Implication: Two Years of Geotail Observations." AGU Fall Meeting Abstracts A1252-

    Viall, N. M., L. Kepko, and H. Spence. 2005. "The Occurrence Rate of Solar Wind Periodic Number Density Structures." AGU Fall Meeting Abstracts 264-

    Guild, T., H. Spence, J. Lyon, et al. C. Goodrich, V. Merkin, and L. Kepko. 2005. "Embedding a Hall MHD plasma sheet simulation inside the Lyon-Fedder-Mobarry global MHD model." AGU Fall Meeting Abstracts A326-

    Kepko, L., M. G. Kivelson, R. L. McPherron, and H. E. Spence. 2004. "Relative timing of substorm onset phenomena." Journal of Geophysical Research (Space Physics) 109 [4203-10.1029/2003JA010285]

    Smart, D. F., M. A. Shea, H. E. Spence, and L. Kepko. 2004. "The Extremes in the Interplanetary Solar Proton Environment and the Two Classes of Solar Events Associated with Very Large > 30 MeV Solar Proton Fluence Events." 35th COSPAR Scientific Assembly 35 3266-

    Merkin, V., C. Goodrich, J. Lyon, et al. M. Wiltberger, W. Wang, and L. Kepko. 2004. "Investigation of Sawtooth activity duing the Halloween Storms of 2003." AGU Fall Meeting Abstracts 7-

    Guild, T., H. Spence, C. Goodrich, J. Lyon, and L. Kepko. 2004. "A Statistical Comparison of the Geotail and MHD Plasma Sheet." AGU Fall Meeting Abstracts A1179-

    Lin, T., H. Spence, L. Kepko, S. P. Gary, and T. Mukai. 2004. "Temperature Anisotropy Constraint In The Plasma Sheet." AGU Fall Meeting Abstracts A1166-

    Spence, H. E., L. Kepko, M. A. Shea, and D. F. Smart. 2004. "Comparison of Solar Energetic Particle Events and Impulsive Nitrate Increases in Greenland Ice Cores." AGU Fall Meeting Abstracts 313-

    Kepko, L., and H. E. Spence. 2004. "Preliminary Results of Nitrate Analysis of Greenland Ice Cores." AGU Fall Meeting Abstracts A1146-

    Goodrich, C., J. Lyon, M. Wiltberger, W. Wang, and L. Kepko. 2004. "Numerical Simulations of the October-November 2003 Super Storms." AGU Fall Meeting Abstracts A2-

    Huang, C., H. Spence, L. Kepko, et al. J. Lyon, C. Goodrich, T. Guild, M. Wiltberger, J. Hughes, and H. Singer. 2003. "Comparison of LFM Simulation With Tsyganenko Models and GOES Observations." AGU Fall Meeting Abstracts A569-

    Spence, H., J. Lyon, L. Kepko, T. Guild, and M. Wiltberger. 2003. "Coupling of Solar Wind Energy to the Magnetosphere via ULF Waves." AGU Fall Meeting Abstracts 1-

    Guild, T., H. Spence, L. Kepko, et al. M. Wiltberger, J. Lyon, C. Goodrich, C. Huang, H. Petschek, J. Hughes, T. Mukai, and S. Kokubun. 2003. "A Statistical Study of Plasma Sheet Parameters in Geotail Data and the LFM MHD Model." AGU Fall Meeting Abstracts 200-

    Kepko, L., and H. E. Spence. 2003. "Observations of discrete, global magnetospheric oscillations directly driven by solar wind density variations." Journal of Geophysical Research (Space Physics) 108 [1257-10.1029/2002JA009676]

    Kepko, L., H. E. Spence, and H. J. Singer. 2002. "ULF waves in the solar wind as direct drivers of magnetospheric pulsations." Geophysical Research Letters 29 [1197-10.1029/2001GL014405]

    Kepko, L., and H. E. Spence. 2002. "Forced Breathing of the Magnetosphere by Solar Wind Dynamic Pressure Variations." AGU Spring Meeting Abstracts 8-

    Spence, H. E., L. Kepko, H. Petschek, et al. T. Guild, E. Huang, S. Lamassa, and S. McCurdy. 2002. "Do Shocks Excite Global Cavity Mode Oscillations?" AGU Spring Meeting Abstracts 9-

    McCurdy, S., H. E. Spence, and L. Kepko. 2002. "Characterizing the Periodicity of Bursty Bulk Flows." AGU Fall Meeting Abstracts 2-

    Spence, H. E., and L. Kepko. 2001. "On the Characteristics of Plasma Sheet Dynamics." AGU Spring Meeting Abstracts 62-

    Kepko, L., M. G. Kivelson, and K. Yumoto. 2001. "Flow bursts, braking, and Pi2 pulsations." Journal of Geophysical Research 106 1903-1916 [10.1029/2000JA000158]

    Elphic, R. C., J. D. Means, R. C. Snare, et al. R. J. Strangeway, L. Kepko, and R. E. Ergun. 2001. "Magnetic Field Instruments for the Fast Auroral Snapshot Explorer." Space Science Reviews 98 151-168

    Henderson, M. G., L. Kepko, H. E. Spence, et al. M. Connors, J. B. Sigwarth, L. A. Frank, and H. J. Singer. 2001. "The evolution of north-south aligned auroral forms into auroral torch structures: The generation of omega bands and Ps6 pulsations via flow bursts." AGU Fall Meeting Abstracts 809-

    Kepko, L., and H. E. Spence. 2001. "Periodicity in the Solar Wind as a Source of ULF Pulsations." AGU Fall Meeting Abstracts A789-

    Spence, H. E., L. Kepko, T. Guild, and E. Huang. 2001. "Post-shock ULF Wave Activity Driven by Dynamic Pressure Variations." AGU Fall Meeting Abstracts 9-

    Kepko, L., and R. L. McPherron. 2001. "Comment on “Evaluation of low-latitude Pi2 pulsations as indicators of substorm onset using Polar ultraviolet imagery” by K. Liou, et al.." J. Geophys. Res. 106 (A9): 18919-18922 [10.1029/2000JA000189]

    Strangeway, R. J., L. Kepko, R. C. Elphic, et al. C. W. Carlson, R. E. Ergun, J. P. McFadden, W. J. Peria, G. T. Delory, C. C. Chaston, M. Temerin, C. A. Cattell, E. Mobius, L. M. Kistler, D. M. Klumpar, W. K. Peterson, E. G. Shelley, and R. F. Pfaff. 1998. "FAST observations of VLF waves in the auroral zone: Evidence of very low plasma densities." Geophysical Research Letters 25 2065-2068 [10.1029/98GL00664]

    Elphic, R. C., J. W. Bonnell, R. J. Strangeway, et al. L. Kepko, R. E. Ergun, J. P. McFadden, C. W. Carlson, W. Peria, C. A. Cattell, D. Klumpar, E. Shelley, W. Peterson, E. Moebius, L. Kistler, and R. Pfaff. 1998. "The auroral current circuit and field-aligned currents observed by FAST." Geophysical Research Letters 25 2033-2036 [10.1029/98GL01158]

    Kivelson, M. G., K. K. Khurana, R. J. Walker, L. Kepko, and D. Xu. 1996. "Flux ropes, interhemispheric conjugacy, and magnetospheric current closure." Journal of Geophysical Research 101 27341-27350 [10.1029/96JA02220]

                                                                                                                                                                                            
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