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Paul Johnson

Photo of Paul Johnson

Address:

4800 Oak Grove Drive
M/S 183-601

Pasadena, CA 91109

Phone:

818.393.4749

Fax:

818.354.5148

Member of:

Planetary Science

Section Manager

Education

  • B.Sc.(honors), Physics, University of Manitoba, Winnipeg MB, Canada (1994)
  • Ph. D., Physics, University of Manitoba, Winnipeg MB, Canada (1999)

Professional Experience

Present Position:

  • Section Manager: Planetary Science Section, Science Division, Jet Propulsion Laboratory, California Institute of Technology (October 2022 - present).

Professional History:

  • Deputy Section Manager: Planetary Science Section, Science Division, Jet Propulsion Laboratory, California Institute of Technology (February 2017-October 2022).
  • Group Supervisor: Planetary Ices Group, Planetary Science Section, Science Division, Jet Propulsion Laboratory, California Institute of Technology (April 2008-February 2017).
  • Research Scientist: Jet Propulsion Laboratory, California Institute of Technology (October 2005-April 2008)
  • Scientist: Jet Propulsion Laboratory, California Institute of Technology (April 2003-September 2005)
  • National Research Council Postdoctoral Research Associate at JPL (January 2001 - April 2003)
  • California Institute of Technology Postdoctoral Scholar at JPL (April 2000 - December 2000)
  • Postdoctoral Scholar at the University of Manitoba (September 1999 - February 2000)

Research Interests

  • Physics and chemistry of planetary ices
  • Electron energy loss spectroscopy and electron impact induced emission spectroscopy involving atomic and molecular species relevant to planetary atmospheres and astrophysical environments.
  • Development of instrumentation for in situ detection and analysis of inorganic and organic compounds on planetary bodies

Selected Awards

  • JPL People Leadership Award, for exceptional and sustained leadership across the Planetary Science Section (2023)
  • NASA Group Achievement Award- Icy Worlds Team (2015)
  • NASA Group Achievement Award Electron Collisions Team (2011)
  • JPL Lew Allen Award for Excellence "in scientific research of atomic and molecular physics, the physics and chemistry of planetary ices, and in situ instrument development" (2007)
  • National Research Council, Resident Research Fellowship (January 2001-April 2003)
  • University of Manitoba Students Union (UMSU) Scholarship (1997)
  • University of Manitoba Graduate Fellowship, Ph.D. (1995-1999)
  • University of Manitoba Graduate Fellowship, M.Sc. (1994-1995)
  • Natural Sciences and Engineering Research Council (NSERC) Summer Research Award (1992, 1993, 1994)
  • Harold R. Coish Memorial Scholarship (1991)
  • Canada Scholarship (1990-1994)

Selected Publications

  1. Vu, T. H., L. R. Reynoso, P. V. Johnson and R. Hodyss (2024) Amino Acid-Mediated Formation of CO2 in Flash-Frozen Ceres Brine, ACS Earth and Space Chemistry, https://doi.org/10.1021/acsearthspacechem.4c00016
  2. Fayolle, E. C., P. V. Johnson, R. Hodyss, X. Zhang, and S. P. Sander (2024) Near-Infrared Vibrational Frequencies of HCN, HNC, and CN in N2 and Ar Ice Matrices, ACS Earth and Space Chemistry, 8(2), 303-309, DOI: 10.1021/acsearthspacechem.3c00287
  3. Parker, C. W., T. H. Vu, T. Kim and P. V. Johnson (2023) Vitreous Magnesium Sulfate Hydrate as a Potential Mechanism for Preservation of Microbial Viability on Europa The Planetary Science Journal 4(9), 178, doi:10.3847/PSJ/aceefa.
  4. Vu, T. H., R. Hodyss, P. V. Johnson and M. L. Cable (2023) Spatial Distribution of Glycine and Aspartic Acid in Rapidly Frozen Brines Relevant to Enceladus The Planetary Science Journal 4(8), 156, doi:10.3847/PSJ/aced90.
  5. P. V. Johnson, T. H Vu, and R. Hodyss, Crystallization Kinetics of Vitreous Magnesium Sulfate Hydrate and Implications for Europa’s Surface, Planetary Science Journal, 4(1), 7 (5pp), (2023)
  6. P. V. Johnson and T. H Vu, Formation of Vitreous Salt Hydrates Under Conditions Relevant to Europa, Planetary Science Journal, 3(7), 151(7pp), (2022)
  7. E. C. Fayolle, A. C. Noell, P. V. Johnson, R. Hodyss, and A. Ponce, Viability of Bacillus subtilis Spores Exposed to Ultraviolet Light at Ocean World Surface Temperatures, Astrobiology, 20(7), pp. 8 (2020)
  8. T. H. Vu, M. Choukroun, R. Hodyss, and P. V. Johnson, Probing Europa's subsurface ocean composition from surface salt minerals using in-situ techniques, Icarus, 349, October (2020), 113746 https://doi.org/10.1016/j.icarus.2020.113746.P. V. Johnson, C. R. Markus, and R. Hodyss, Photochemistry of Ozone–Water Ices, ACS Earth and Space Chemistry Article ASAP, (2019) DOI: 10.1021/acsearthspacechem.9b00189
  9. P. V. Johnson, C. R. Markus, and R. Hodyss, Photochemistry of Ozone–Water Ices, ACS Earth and Space Chemistry Article ASAP, (2019) DOI: 10.1021/acsearthspacechem.9b00189
  10. R. Hodyss, P. V. Johnson, S. M. Meckeler, and E. C. Fayolle, Ultraviolet Spectroscopy and Photochemistry of SO2/H2O Ices, ACS Earth and Space Chemistry, 3(4), 663-668 (2019) DOI: 10.1021/acsearthspacechem.9b00034.
  11. P. V. Johnson, R. Hodyss, T. H. Vu, and Mathieu Choukroun, Insights into Europa’s Ocean Composition Derived from Its Surface Expression, Icarus, 321, 857-865 (2019) https://doi.org/10.1016/j.icarus.2018.12.009.
  12. E. C. Thomas, T. H. Vu, R. Hodyss, P. V. Johnson, Mathieu Choukroun, Kinetic Effect on the Freezing of Ammonium-Sodium-Carbonate-Chloride Brines and Implications for the Origin of Ceres’ Bright Spots, Icarus, 320, 150-158 DOI 10.1016/j.icarus.2017.12.038 (2019)
  13. X. Liu, D. E. Shemansky, J. Yoshii, M. J. Liu, P. V. Johnson, C. P. Malone and M. A. Khakoo, H2 X 1Σg+ – c 3Πu Excitation by electron impact: energies, spectra, emission yields, cross-sections, and H(1s) kinetic energy distributions The Astrophysical Journal Supplement Series 232(2), 19, (2017)
  14. J. M. Ajello, C. P. Malone, G. M. Holsclaw, A. C. Hoskins, R. W. Eastes, W. E. McClintock, and P. V. Johnson, Electron Impact Study of the 100 eV Emission Cross-Section and Lifetime of the Lyman-Birge-Hopfield Band System of N2: Direct Excitation and Cascade, Journal of Geophysical Research: Space Physics, 122, 6776-6790, (2017), DOI: 0.1002/2017JA024087 
  15. T. H. Vu, R. Hodyss, P. V. Johnson, M. Choukroun, Preferential Formation of Sodium Salts from Frozen Sodium-Ammonium-Chloride-Carbonate Brines – Implications for Ceres’ Bright Spots, Planetary Space Science, 141, 73-77, DOI: 10.1016/j.pss.2017.04.014 (2017)
  16. E. C. Thomas, R. Hodyss, T. H. Vu, P. V. Johnson, Mathieu Choukroun, Composition and Evolution of Frozen Chloride Brines Under the Surface Conditions of Europa, ACS Earth and Space Chemistry, 1 (1), pp 14–23 (2017)
  17. X. Liu, D. E Shemansky, J. Yoshii, M. J. Liu, P. V. Johnson, and C. P. Malone, Energies, transition probabilities, predissociation rates, and lifetimes of the H2, HD, and D2 c 3Π state, Journal of Physics B: Atomic, Molecular and Optical Physics, 50 (3), 035101(2017).
  18. T. H. Vu, R. Hodyss, M. Choukroun, and P. V. Johnson, Chemistry of Frozen Sodium,-Magnesium-Sulfate-Chloride Brines:  Implications for Surface Expression of Europa’s Ocean Composition, The Astrophysical Journal Letters, 816(L26) (6pp) (2016) doi:10.3847/2041-8205/816/2/L26
  19. X. Liu, D. E. Shemansky, J. Yoshi, P. V. Johnson, C. P. Malone, and J. M. Ajello, Spectra, emission yields, cross sections, and kinetic energy distributions of hydrogen atoms from H2 X 1Σ – d 3Πu excitation by electron impact, The Astrophysical Journal, 818(2) (17pp) (2016) doi:10.3847/0004-637X/818/2/120.
  20. C. Noell, T. Ely, D. K. Bolser, H. Darrach, R. Hodyss, P. V. Johnson, J. D. Hein, and A. Ponce, Spectroscopy and viability of Bacillus subtilis spores after ultraviolet irradiation: Implications for the detection of potential bacterial life on Europa, Astrobiology, 15(1), 20-31 DOI: 10.1089/ast.2014.1169.
  21. P. V. Johnson, R. Hodyss, J. L. Beauchamp, Ion Funnel Augmented Mars Atmospheric Pressure Photoionization Mass Spectrometry for In Situ Detection of Organic Molecules, Journal of the American Society for Mass Spectrometry, 25(1), 1832-1840, (2014), DOI: 10.1007/s13361-014-0930-z.
  22. P. V. Johnson, R. Hodyss, V. F. Chernow, D. M. Lipscomb, and J. D. Goguen, Ultraviolet Photolysis of Amino Acids on the Surface of Icy Solar System Bodies, Icarus, 221(2), 800-805 (2012).
  23. C. P. Malone, P. V. Johnson, X. Liu, B. Ajdari, I. Kanik, and M. A. Khakoo, Integral Cross Sections for the Electron Impact Excitation of the b 1πu, c3 1πu, o3 1πu, b′ 1∑ +u, c4′ 1∑ +u, G 3πu, and F 3πu states of N2, Physical Review A: Atomic, Molecular, Optical Physics, 85, 062704 (17pp) (2012).
  24. X. Liu, D. E. Shemansky, P. V. Johnson, C. P Malone, and M. A. Khakoo, Electron and photon dissociation cross sections of the D2 singlet ungerade continua, Journal of Physics B: Atomic, Molecular and Optical Physics, 45, 105203 (16pp) (2012), doi:10.1088/0953-4075/45/10/105203.
  25. N. Heays, B. R. Lewis, S. T. Gibson, C. P. Malone, P. V. Johnson, I. Kanik, M. A. Khakoo, Tuning out vibrational levels in molecular electron energy-loss spectra, Physical Review A: Atomic, Molecular, Optical Physics, 85, 012705 (8pp) (2012).
  26. X. Liu, D. E. Shemansky, P. V. Johnson, C. P Malone, M. A. Khakoo, and I. Kanik, Electron and photon dissociation cross sections of the H2 singlet ungerade continua, Journal of Physics B: Atomic, Molecular and Optical Physics, 45, 015201 (15pp) (2011), doi:10.1088/0953-4075/45/1/015201.
  27. P. V. Johnson, J. A. Young, C. P. Malone, M. A. Khakoo, X Liu and I. Kanik, Electron impact processes in nitrogen rich atmospheres of the outer solar system, Journal of Physics: Conference Series, 204(1): 012003 (5pp) (2010).
  28. R. Hodyss, C. D. Parkinson, P. V. Johnson, J. V. Stern, J. D. Goguen, Y. L. Yung, and I. Kanik, Methanol on Enceladus, Geophysical Research Letters, 36, L17103 (3pp) (2009).
  29. S. Weber, R. Hodyss, P. V. Johnson, K. Willacy, and I. Kanik, Hydrogen-deuterium exchange in photolyzed methane-water ices, The Astrophysical Journal, 703 1030-1033 (2009).
  30. X. Liu, P. V. Johnson, C. P. Malone, J. A. Young, D. E. Shemansky and I. Kanik, Electron impact excitation and emission cross section of the H2 B' 1Σ+u, and D 1Πu states and rotational dependence of photodissociation cross sections of the B' 1Σ+uand D 1Πu continua, Journal of Physics B: Atomic, Molecular and Optical Physics, 42, 185203 (13pp) (2009).
  31. J. A. Young, C. P. Malone, P. V. Johnson, X. Liu and I. Kanik, Dissociative Excitation of NO2 by Electron Impact, Journal of Physics B: Atomic, Molecular and Optical Physics, 42, 185201 (10pp) (2009).
  32. C. P. Malone, P. V. Johnson, I. Kanik, B. Ajdari, S. S. Rahman, S. S. Bata, A. Emigh, and M. A. Khakoo, Electron Impact Excitation of Molecular Nitrogen. II. Vibrationally-Resolved Excitation of the C3Πu (v') State, Physical Review A: Atomic, Molecular, and Optical Physics, 79, 032705, 1-9 (2009).
  33. C. P. Malone, P. V. Johnson, I. Kanik, B. Ajdari, and M. A. Khakoo, Electron-Impact Excitation of Molecular Nitrogen. I. Excitation of the C 3Πu, E' 3Σ+g, and a" 1Σ+g States, Physical Review A: Atomic, Molecular, and Optical Physics, 79, 032704, 1-16 (2009).
  34. R. Hodyss, P. V. Johnson, J. V. Stern, J. D. Goguen, and I. Kanik, Photochemistry of Methane-Water Ices, Icarus, 200, 338-342 (2009).
  35. *J. W. McConkey, C. P. Malone, P. V. Johnson, C. Winstead, V. McKoy, and I. Kanik, Electron Impact Dissociation of Oxygen-Containing Molecules - A Critical Review, Physics Reports, 466, 1-103 (2008).
  36. R. P. Hodyss, J. D. Goguen, P. V. Johnson, C. Campbell, and I. Kanik, Release of N2, CH4, CO2, and H2O from surface ices on Enceladus, Icarus, 197, 152-156 (2008).
  37. C. P. Malone, P. V. Johnson, J. W. McConkey and I. Kanik Cross sections for the O II (83.4 nm) emission from electron impact on O2, Journal of Geophysical Research: Space Physics. 113, A06309, doi:10.1029/2008JA013160 (2008).
  38. C. P. Malone, P. V. Johnson, J. W. McConkey, J. M. Ajello, and I. Kanik, Dissocitative Excitation of N2O by Electron-Impact, Journal of Physics B: Atomic, Molecular, and Optical Physics, 41 095201 (9pp) (2008).
  39. H. Kim, H. I. Kim, P. V. Johnson, L. W. Beegle, J. L. Beauchamp ,W. A. Goddard, and I. Kanik, Ion Mobility Study of Choline and Other Ammonium Cations in N2: Experimental and Theoretical Investigations of Mass-Mobility Correlation, Analytical Chemistry, 80, 1928-1936 (2008).
  40. R. Hodyss, P. V. Johnson, G. E. Orzechowska, and I. Kanik, Carbon dioxide segregation in mixed CO2:H2O ices, Icarus, 194, 836-842 (2008).
  41. X. Liu, D. E. Shemansky, C. P. Malone, P. V. Johnson, J. M. Ajello, I. Kanik, A. N. Heays, B. R. Lewis, S. T. Gibson, and G. Stark, Experimental and Coupled-Channels Investigation of the Radiative Properties of the N2c'4 1Σ+u-X1Σ+g Band System, Journal of Geophysical Research-Space Physics 113, A02304 (2008).

Projects

Habitability of Hydrocarbon Worlds: Titan and Beyond
NASA Astrobiology Institute: Icy Worlds