NASA Logo Jet Propulsion Laboratory California Institute of Technology View the NASA Portal
NASA Banner
NASA Banner
NASA Banner
NASA Banner
JPL Science
JPL Science Division Home
Planetary Science Planetary Science
Earth and Planetary Atmospheres
Geophysics & Planetary Geosciences
Asteroids, Comets & Satellites
Planetary Chemistry and Astrobiology
Planetary Ices
Astrophysics & Space Sciences Astrophysics & Space Sciences
Earth Science Earth Science
Center for Climate Sciences
Solid Earth
Earth Surface Science
Water and Carbon Cycles
Oceans and Ice
Ocean Circulation
Climate Physics
Atmospheric Observations
Table Mountain Research
Laboratory Studies and Modeling
Microwave Atmospheric Science
Tropospheric Sounding, Assimilation, and Modeling (TSAM)
AIRS Atmospheric Science
Aerosol and Cloud Science
Directorate Science Affiliates Directorate Science Affiliates
Open Postdoc Positions Open Postdoc Positions
Brochures Brochures
 Earth Surface Science: People
Ashley Davies's Picture
Jet Propulsion Laboratory
M/S 183-501
4800 Oak Grove Drive
Pasadena, CA 91109
Curriculum Vitae:

Ashley Davies

  • B.Sc (Hons.) in Astronomy and Geology, Hatfield Polytechnic, Hatfield, Herts. UK (1984)
  • Ph.D. in Volcanology, Lancaster University, Lancaster, UK (1988)

Research Interests
  • Planetary science: in particular, the jovian satellite Io
  • Remote sensing of volcanic activity
  • Hyperspectral and multispectral data analysis
  • Numerical and analytical modelling of volcanic processes on Io, Earth, and icy satellites
  • Autonomous spacecraft and sensor web operations


Autonomous Spacercraft Experiment (ASE) Icon Autonomous Spacercraft Experiment (ASE)
The Autonomous Sciencecraft Experiment (ASE) is operating onboard the Earth Observing-1 mission since 2003.

Volcano Sensor Web Icon Volcano Sensor Web
The Sensor Web Project uses a network of sensors linked by software and the internet to an autonomous satellite observation response capability.

ASTER Volcano Archive (AVA) Icon ASTER Volcano Archive (AVA)
This website provides access to a substantial part of the ASTER Volcano Archive (AVA) image data acquired over the life of the ASTER mission.

Professional Experience
  • Jet Propulsion Laboratory (1996 - present)
    • NMP-Autonomous Sciencecraft Experiment Lead Scientist (2001-present)
    • ASTER Team Associate (2004-present)
    • Research Scientist, Comets, Asteroids and Satellites Group (2003 - present)
    • Research Scientist, Galileo NIMS team (2001-2002)
    • Scientist, Galileo NIMS team (1996-2001)
  • National Research Council Resident Research Associate, NASA JPL (1994-1996)
  • UK Meteorological Office: Higher Scientific Officer (1990 - 1994)
    • ARTIFAX Systems Programmer (1990-1991)
    • Short-Range Forecast Division (Research Scientist)

Selected Awards
  • NASA Software of the Year - Autonomous Sciencecraft Experiment (2005)
  • NASA Group Achievement Award for the Autonomous Sciencecraft Experiment Team (2005)
  • Technical Innovation resulting in a NASA Tech Brief: "Software for the Techsat-21 Autonomous Sciencecraft Constellation (ASC)" (2003)
  • NASA Tech Brief award "Software for Onboard Science Analysis" (2003)
  • Technically Significant Technology Award "Software for the Techsat 21 Autonomous Sciencecraft Experiment (ASE)" (2003)
  • JPL Team Bonus Award: "Jupiter Icy Moon Orbiter (JIMO) Studies" (2003)
  • NASA Group Achievement Award to the Galileo Project Team (1998)
  • NASA Group Achievement Award to the Galileo Orbital Operations Recovery Team (1997)
  • National Research Council Postdoctoral Fellowship (1994-1996)

Selected Publications


  1. "Volcanism on Io: a Comparison with Earth", A. G. Davies (2007) Cambridge University Press, Planetary Science Series no. 7. 372 pages.

Selection of Publications (see link to CV for complete list)

  1. Cataldo, E., A. G. Davies and L. Wilson (2013) Near-vertical supersonic and shock-free gas/magma flow at fissure volcanoes: Application to Pillan, Io. Icarus, 226, 1171-1176. doi.10.1016/j.icarus.2013.06.035.
  2. Davies, A. G., S. Chien, J. Doubleday, D. Tran, T. Thordarson, M. T. Gudmundsson, Á. Höskuldsson, S. S. Jakobsdóttir, R. Wright and D. Mandl (2013) Observing Iceland's Eyjafjallajökull 2010 Eruptions with the Autonomous NASA Volcano Sensor Web, JGR-Solid Earth, 118, 1-21, doi:10.1002/jgrb.50141.
  3. Chien, S., D. McLaren, D. Tran, A. G. Davies, J. Doubleday and D. Mandl (2013) Onboard Product Generation on Earth Observing One: A pathfinder for the proposed HyspIRI Mission Intelligent Payload Module. Special Issue on the Earth Observing One (EO-1) Satellite Mission: Ten Years in Space, IEEE JSTARS, 6, no. 2, 257-264.
  4. Davies, A. G., G. J. Veeder, D. L. Matson and T. V. Johnson (2012) Charting thermal emission variability at Pele, Janus Patera and Kanehekili Fluctus with the Galileo NIMS Io Thermal Emission Database (NITED), Icarus, 221, 466-470. doi:10.1016/j.icarus.2012.04.01.
  5. Matson, D. L., J. C. Castillo-Rogez, A. G. Davies, T. V. Johnson and J. Lunine (2012) Enceladus: A Hypothesis For Bringing Both Heat And Chemicals To the Surface, Icarus, 221, 53-62.
  6. Davies, A. G., G. J. Veeder, D. L. Matson and T. V. Johnson (2012) Charting thermal emission variability at Pele, Janus Patera and Kanehekili Fluctus with the Galileo NIMS Io Thermal Emission Database (NITED), Icarus. In press. doi:10.1016/j.icarus.2012.04.01.
  7. Veeder, G. J., A. G. Davies, D. L. Matson, T. V. Johnson, D. A. Williams and J. Radebaugh (2012) Io: Volcanic Thermal Sources and Global Heat Flow, Icarus. doi:10.1016/j.icarus.2012.04.004. 219, 701-722.
  8. Davies, A. G., G. J. Veeder, D. L. Matson and T. V. Johnson (2012) Io: Charting thermal emission variability with the Galileo NIMS Io Thermal Emission Database (NITED): Loki Patera, Geophysical Research Letters, 39, L01201, doi:10.1029/2011GL049999.
  9. Davies, A. G., L. Keszthelyi and A. S. McEwen (2011) Estimating Eruption Temperature From Thermal Emission Spectra of Lava Fountain Activity in the Erta'Ale (Ethiopia) Volcano Lava Lake - Implications for Observing Io's Volcanoes, GRL, 38, L21308, doi: 10.1029/2011GL049418.
  10. Davies A. G. (2011) Lava lakes on Earth and Io, Planetary Report, vol. XXXI, no. 2, 10-15.
  11. Davies A. G. and M. E. Ennis (2011) The variability of volcanic activity at Zamama, Culann, and Tupan Patera on Io as seen by the Galileo Near Infrared Mapping Spectrometer, Icarus, 215, 401-416.
  12. Wright, R. H. Garbeil and A. G. Davies (2011) The cooling rate of some active lavas determined using an orbital imaging spectrometer, JGR (Solid Earth), 115, B06205, doi:10.1029/2009JB006536.
  13. Davies, A. G., C. Sotin, D. L. Matson, J. C. Castillo-Rogez, T. V. Johnson, M. Choukroun, and K. H. Baines (2010) Atmospheric control of the cooling rate of impact melts and cryolavas on Titan's surface, Icarus, 208, 887-895, doi:10.1016/j.icarus.2010.02.025.
  14. Davies, A.G., L. P. Keszthelyi and A. J. L. Harris (2010) The Thermal Signature of Volcanic Eruptions on Io and Earth, JVGR, 194, 75-99, doi:10.1016/j.jvolgeores.2010.04.009.
  15. Leone, G., A. G. Davies, L. Wilson, D. A. Williams, L. P. Keszthelyi, W. L. Jaeger and E. P. Turtle (2009) Volcanic history, geologic analysis and map of the Prometheus Patera region on Io, Icarus, 187, 93-105.
  16. Davies, A. G., J. Calkins, L. Scharenbroich, R. G. Vaughan, R. Wright, P. Kyle, R. Castańo, S. Chien, and D. Tran (2008) Multi-Instrument Remote and In Situ Observations of the Erebus Volcano (Antarctica) Lava Lake in 2005: a Comparison with the Pele Lava Lake on the Jovian Moon Io, J. Volc. Geotherm. Res., 177, v3, 705-724.
  17. Keszthelyi, L. P., W. Jaeger, M. Milazzo, J. Radebaugh, A. G. Davies and K. Mitchell (2007) New estimates for Io eruption temperatures: implications for the interior, Icarus, 192, 491-502.
  18. Matson, D. L., A. G. Davies, J. A. Rathbun, G. J. Veeder, T. V. Johnson and J. C. Castillo (2006) Io: Loki Patera as a magma sea, JGR-Planets, 111, E09002, doi:10.1029/2006JE002703.
  19. Davies, A. G., L. Wilson, D. L. Matson, G. Leone, L. P. Keszthelyi and W. Jaeger (2006) The pulse of the volcano: discovery of episodic activity at Prometheus on Io, Icarus, 184, 460-477.
  20. Davies, A. G., S. Chien, V. Baker, T. Doggett, J. Dohm, R. Greeley, F. Ip, R. Castaňo, B. Cichy, G. Rabideau, D. Tran and R. Sherwood (2006) Monitoring Active Volcanism with the Autonomous Sciencecraft Experiment on EO-1, Rem. Sens. Environ., 101, no. 4, 427-446.
  21. Doggett, T., R. Greeley, A. G. Davies, S. Chien, B. Cichy, R. Castano, K. Williams, V. Baker, J. Dohm and F. Ip (2006) Autonomous detection of cryospheric change with Hyperion onboard Earth-Observing 1, Rem. Sens. Environ., 101, no. 4, 447-462.
  22. Davies, A. G., S. Chien, R. Wright, A. Miklius, P. R. Kyle, M. Welsh, J. B. Johnson, D. Tran, S. R. Schaffer, and R. Sherwood (2006) Sensor web enables rapid response to volcanic activity, Eos, 87 (1), 1&5.
  23. Davies, A. G., D. L. Matson, G. J. Veeder, T. V. Johnson and D. L. Blaney (2005) Post-solidification cooling and the age of Io's lava flows, Icarus, 176, 123-137.
  24. Marchis, F., D. Le Mignant, F. H. Chaffee, A. G. Davies, S. H. Kwok, R. Prange, I. de Pater, P. Amico, R. Campbell, T. Fusco et al. (2005) Keck AO survey of Io global volcanic activity between 2 and 5 µm, Icarus, 176, 96-122.
  25. Schenk, P., R. Wilson and A. G. Davies (2004) Shield volcano topography and rheology of flows on Io, Icarus, 169, 98-110.
  26. Davies, A. G. (2003) Volcanism on Io: estimation of eruption parameters from Galileo NIMS data. J. Geophys. Res., 108, 5106-5120.
  27. Davies, A. G., (2003) Temperature, Age and Crust Thickness Distributions of Loki Patera on Io from Galileo NIMS data: Implications for Resurfacing Mechanism. Geophysical Research Letters, 30, 2133-2136.
  28. Rathbun, J., J. R. Spencer, A. G. Davies, R. R. Howell and L. Wilson (2002) Loki: a predictable volcano? Geophysical Research Letters, 29, no 10, 84-88.
  29. Marchis, F., I. dePater, A. G. Davies, H. G. Roe, T. Fusco, D. Le Mignant, P. Deschamps, B. A. Mackintosh and R. Prange (2002) High-resolution Keck adaptive optics imaging of violent activity on Io. Icarus, 160, 124-131.
  30. Davies, A. G., L. P. Keszthelyi, D. Williams, C. B. Phillips, A. S. McEwen, R. M. C. Lopes, W.D. Smythe, L. W. Kamp, L. A. Soderblom and R. W. Carlson (2001) Thermal signature, eruption style and eruption evolution at Pele and Pillan on Io. J. Geophys. Res., 106, E12, 33,079-33,104.
  31. Williams, D. A., A. G. Davies, L. P. Keszthelyi and R. Greeley (2001) The Summer 1997 eruption at Pillan Patera on Io: implications for ultrabasic lava flow emplacement, J. Geophys. Res., 106, E12, 33,105-33,120.
  32. Davies, A. G., R. Lopes-Gautier, W.D. Smythe and R.W. Carlson (2000) Silicate cooling model fits to Galileo NIMS data of volcanism on Io. Icarus, 148, 212-225.
  33. Davies, A. G., A. S. McEwen, R. Lopes-Gautier, L. Keszthelyi, R. W. Carlson and W. D. Smythe (1997) Temperature and Area constraints of the South Volund volcano on Io from the NIMS and SSI Instruments during the Galileo G1 orbit. Geophysical Research Letters, 24, 2447-2450.
  34. Davies, A. G. (1996) Io's volcanism: thermo-physical models of silicate lavas compared with observations of thermal emission. Icarus, 124, no 1, 45-61.

Group Home Page
People in this Group
Group Projects

JPL Privacy Statement Sitemap Email Contact Form