Bethany L. Ehlmann

Office: 161 South Mudd (Geophysics) (21)

Phone: 626-395-6720

Email: [email protected]

Mail Code: MC 150-21

Administrative Assistant

Name: Stephanie Petty

Phone: 626-395-3734

Research Website

Home / People / Bethany L. Ehlmann

Professor of Planetary Science; Allen V. C. Davis and Lenabelle Davis Leadership Chair, Keck Institute for Space Studies; Director, Keck Institute for Space Studies

A.B., Washington University in St. Louis, 2004; M.Sc., University of Oxford, 2005; M.Sc., 2007; M.S., Brown University, 2008; Ph.D., 2010. Assistant Professor, Caltech, 2011-17; Professor, 2017-; Davis Leadership Chair, Keck Institute for Space Studies, 2023-; Jet Propulsion Laboratory Research Scientist, 2011-20; Associate Director, 2018-23; Director, Keck Institute for Space Studies, 2023-.

Research Summary

Remote compositional analysis of planetary surfaces; environmental change over Mars history; chemical and physical weathering processes on terrestrial planets; infrared spectroscopy and quantitative radiative transfer modeling; habitability, rock-microbe interactions, biomarker preservation; early Earth surface environments; environmental science and applications of remote sensing; science policy.

Research Options

Geology; Planetary Science;

Research Areas

Mission Instrumentation; Planetary Geosciences; Remote Sensing; Spectroscopy;

Please see my research page for a description of my ongoing research projects. (http://www.ehlmann.caltech.edu/)

For a complete publications list, see

http://www.ehlmann.caltech.edu/publications/index.html

Stein, N. T., Ehlmann, B. L. et al. (2017) The formation and evolution of bright spots on Ceres. Icarus . ISSN 0019-1035. http://resolver.caltech.edu/CaltechAUTHORS:20171106-092332060

Lapotre, M. G. A. and Ehlmann, B. L. and Minson, S. E. (2017) A Probabilistic Approach to Remote Compositional Analysis of Planetary Surfaces. Journal of Geophysical Research: Planets, 122 (5). pp. 983-1009. ISSN 2169-9100. http://resolver.caltech.edu/CaltechAUTHORS:20170302-115016869

Bridges, Nathan T. and Ehlmann, Bethany L. (2017) The Mars Science Laboratory (MSL) Bagnold Dunes campaign, Phase I: Overview and introduction to the special issue. Journal of Geophysical Research. Planets, 123 (1). pp. 3-19. ISSN 2169-9097. http://resolver.caltech.edu/CaltechAUTHORS:20170919-104510502

Ehlmann, B. L. and Edgett, K. S. and Sutter, B. et al. (2017) Chemistry, Mineralogy, and Grain Properties at Namib and High Dunes, Bagnold Dune Field, Gale Crater, Mars: A Synthesis of Curiosity Rover Observations. Journal of Geophysical Research. Planets, 122 (12). pp. 2510-2543. ISSN 2169-9097. http://resolver.caltech.edu/CaltechAUTHORS:20170612-135954084

Hu, R, DM Kass, BL Ehlmann, Y Yung. Tracing the fate of carbonate and the atmospheric evolution of Mars, Nature Communications, doi: 10.1038/ncomms10003, 2015

Edwards, CS and BL Ehlmann. Carbon sequestration on Mars, Geology, doi:10.1130/G36983.1, 2015

Greenberger, R, JF Mustard, BL Ehlmann, DL Blaney, EA Cloutis, JH Wilson, RO Green, AA Fraeman, Imaging spectroscopy of geological samples and outcrops: novel insights from microns to meters, GSA Today, GSA Today, 25(12) doi: 10.1130/GSATG252A.1, 2015

Ehlmann, Bethany L. and Edwards, Christopher S. (2014) Mineralogy of the Martian Surface. Annual Review of Earth and Planetary Sciences, 42 . pp. 291-315. ISSN 0084-6597. http://resolver.caltech.edu/CaltechAUTHORS:20140228-083724476

Hu, Renyu and Ehlmann, Bethany L. and Seager, Sara (2012) Theoretical Spectra of Terrestrial Exoplanet Surfaces. Astrophysical Journal, 752 (1). Art. No. 7. ISSN 0004-637X. http://resolver.caltech.edu/CaltechAUTHORS:20120716-142432888

Ehlmann, Bethany L. et al. (2011) Subsurface water and clay mineral formation during the early history of Mars. Nature, 479 (7371). pp. 53-60. ISSN 0028-0836. http://resolver.caltech.edu/CaltechAUTHORS:20111121-112809475

Ehlmann, B. L. and Mustard, J. F. and Murchie, S. L. (2010) Geologic setting of serpentine deposits on Mars. Geophysical Research Letters, 37 . Art. No. L06201. ISSN 0094-8276. http://resolver.caltech.edu/CaltechAUTHORS:20121016-091235443

Ehlmann, Bethany L. et al. (2009) Identification of hydrated silicate minerals on Mars using MRO-CRISM: Geologic context near Nili Fossae and implications for aqueous alteration. Journal of Geophysical Research E, 114 . Art. No. E00D08. ISSN 0148-0227. http://resolver.caltech.edu/CaltechAUTHORS:20121016-082328715

Ehlmann, Bethany L. et al. (2008) Orbital Identification of Carbonate-Bearing Rocks on Mars. Science, 322 (5909). pp. 1828-1832. ISSN 0036-8075. http://resolver.caltech.edu/CaltechAUTHORS:20121016-112524059

Ehlmann , Bethany L. et al. (2008) Clay minerals in delta deposits and organic preservation potential on Mars. Nature Geoscience, 1 (6). pp. 355-358. ISSN 1752-0894. http://resolver.caltech.edu/CaltechAUTHORS:20121017-113424651

Ge 103. Introduction to the Solar System. 9 units (3-0-6); third term, 2022-23. Prerequisites: instructor's permission. Formation and evolution of the solar system. Interiors, surfaces, and atmospheres. Orbital dynamics, chaos, and tidal friction. Cratering. Comets and asteroids. Extrasolar planetary systems.
Instructor: Ehlmann

Ge/Ay 11 c. Introduction to Earth and Planetary Sciences: Planetary Sciences. 9 units (3-0-6); third term, 2022-23. Prerequisites: Ma 1 ab, Ph 1 ab. A broad introduction to the present state and early history of the solar system, including terrestrial planets, giant planets, moons, asteroids, comets, and rings. Earth-based observations, observations by planetary spacecraft, study of meteorites, and observations of extrasolar planets are used to constrain models of the dynamical and chemical processes of planetary systems. Although Ge 11 abcd is designed as a sequence, any one term may be taken as a standalone course. Physicists and astronomers are particularly welcome.
Instructor: Ehlmann

Ge 116. Analytical Techniques Laboratory. 9 units (1-4-4); second term, 2022-23. Prerequisites: Ge 114 a or instructor's permission. Methods of quantitative laboratory analysis of rocks, minerals, and fluids in geological and planetary sciences. Consists of five intensive two-week modules covering scanning electron microscopy (imaging, energy-dispersive X-ray spectroscopy, electron backscatter diffraction); the electron microprobe (wavelength-dispersive X-ray spectroscopy); X-ray powder diffraction; optical, infrared, and Raman spectroscopy; and plasma source mass spectrometry for elemental and radiogenic isotope analysis. Satisfies the Institute core requirement for an additional introductory laboratory course.
Instructors: Asimow, Ehlmann, Jackson

Ge/EE/ESE 157 c. Remote Sensing for Environmental and Geological Applications. 9 units (3-3-3); third term, 2022-23. Analysis of electromagnetic radiation at visible, infrared, and radio wavelengths for interpretation of the physical and chemical characteristics of the surfaces of Earth and other planets. Topics: interaction of light with materials, spectroscopy of minerals and vegetation, atmospheric removal, image analysis, classification, and multi-temporal studies. This course does not require but is complementary to EE 157 ab with emphasis on applications for geological and environmental problems, using data acquired from airborne and orbiting remote sensing platforms. Students will work with digital remote sensing datasets in the laboratory and there will be one field trip.
Instructor: Ehlmann

Ge/EE/ESE 157 c. Remote Sensing for Environmental and Geological Applications. 9 units (3-3-3); third term, 2021-22. Analysis of electromagnetic radiation at visible, infrared, and radio wavelengths for interpretation of the physical and chemical characteristics of the surfaces of Earth and other planets. Topics: interaction of light with materials, spectroscopy of minerals and vegetation, atmospheric removal, image analysis, classification, and multi-temporal studies. This course does not require but is complementary to EE 157ab with emphasis on applications for geological and environmental problems, using data acquired from airborne and orbiting remote sensing platforms. Students will work with digital remote sensing datasets in the laboratory and there will be one field trip.
Instructor: Ehlmann

Ge 151. Planetary Surfaces. 9 units (3-3-3); first term, 2020-21. We will review the mechanisms responsible for the formation and modification of the surfaces of solar system bodies, studying both composition and physical processes. Topics include exogenous processes (impact cratering, space weathering) and endogenous processes (tectonic, volcanic, weathering, fluvial, aeolian, and periglacial) that shape the surfaces of planets. Lectures, occasional labs, and one required field trip.
Instructor: Ehlmann

Ge/EE/ESE 157 c. Remote Sensing for Environmental and Geological Applications. 9 units (3-3-3); third term, 2020-21. Analysis of electromagnetic radiation at visible, infrared, and radio wavelengths for interpretation of the physical and chemical characteristics of the surfaces of Earth and other planets. Topics: interaction of light with materials, spectroscopy of minerals and vegetation, atmospheric removal, image analysis, classification, and multi-temporal studies. This course does not require but is complementary to EE 157ab with emphasis on applications for geological and environmental problems, using data acquired from airborne and orbiting remote sensing platforms. Students will work with digital remote sensing datasets in the laboratory and there will be one field trip.
Instructor: Ehlmann

Ge 151. Planetary Surfaces. 9 units (3-3-3); first term, 2019-20. Exogenous (impact cratering, space weathering) and endogenous (tectonic, volcanic, weathering, fluvial, aeolian, and periglacial) processes shape the surfaces of planets. We will review the mechanisms responsible for the formation and modification of the surfaces of solar system bodies, studying both composition and physical processes.
Instructor: Ehlmann

Ge/EE/ESE 157 c. Remote Sensing for Environmental and Geological Applications. 9 units (3-3-3); third term, 2019-20. Analysis of electromagnetic radiation at visible, infrared, and radio wavelengths for interpretation of the physical and chemical characteristics of the surfaces of Earth and other planets. Topics: interaction of light with materials, spectroscopy of minerals and vegetation, atmospheric removal, image analysis, classification, and multi-temporal studies. This course does not require but is complementary to EE 157ab with emphasis on applications for geological and environmental problems, using data acquired from airborne and orbiting remote sensing platforms. Students will work with digital remote sensing datasets in the laboratory and there will be one field trip. Not offered 2019-20.
Instructor: Ehlmann