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Photo of Joshua Cahill

Joshua Cahill

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Planetary Geologist; UV to TIR Spectroscopist; Synthetic Aperture and Sounding Radar Scientist
240-228-3048
  • Doctor of Philosophy, Geology and Geophysics
    2009, University of Hawaii Manoa
  • Master of Science, Geology
    2003, University of Tennessee
  • Bachelor of Science , Science-Business
    2000, University of Notre Dame

I have experience in the fields of lunar and terrestrial remote sensing.  My primary focus in lunar remote sensing is the application of radiative transfer modeling for analysis of visible/near-infrared spectra to determine crustal composition in the context of Apollo soils and samples.  I have also sustained involvement in terrestrial studies using a variety of airborne and portable field sensors for hyperspectral (visible, near, and thermal infrared) analyses of many targets.  More recent activities include participation on NASA’s Lunar Reconnaissance Orbiter (LRO) mission supporting the Mini-RF S-band radar and Lyman Alpha Mapping Project (LAMP) payloads including observation targeting, calibration, validation, and scientific analysis. My research for this mission has focused on characterization of the physical properties of lunar surface and subsurface geology. I'm also a Co-I supporting the NASA/APL SSERVI Node VORTICES, studying volatile detection and processes on a variety of airless bodies.

Notable Awards and Leadership

Year(s) Description
2000 - Present American Geophysical Union
2015 - 2016 Geochemical Society
2013 NASA Achievement for supporting Lunar Reconnaissance Orbiter Science Team (Mini-RF)
2011 NASA Achievement for supporting Lunar Reconnaissance Orbiter Mission Operations (Mini-RF)

Scholarly Publications

optical constants of iron and nickel metal and an assessment of their relative influences on silicate mixture spectra from the FUV to the NIR

Icarus, 2019
Joshua T. S. Cahill, David T. Blewett, Nhan V. Nguyen, Alex Boosalis, Samuel J. Lawrence, Brett W. Denevi, (2019), optical constants of iron and nickel metal and an assessment of their relative influences on silicate mixture spectra from the FUV to the NIR, Icarus, 317, 229-241

The Far Ultraviolet Wavelength Dependence of the Lunar Phase Curve as Seen by LRO LAMP

Journal of Geophysical Research-Planets, 2018
Y. Liu, K. D. Retherford, T. K. Greathouse, U. Raut, K. E. Mandt, A. R. Hendrix, J. T. S. Cahill, G. R. Gladstone, C. Grava, A. F. Egan, D. E. Kaufmann, W. R. Pryor, (2018), The Far Ultraviolet Wavelength Dependence of the Lunar Phase Curve as Seen by LRO LAMP, Journal of Geophysical Research-Planets, 123, 2550-2563

Image Reconstruction Techniques in Neutron and Gamma Ray Spectroscopy: improving Lunar Prospector Data

Journal of Geophysical Research-Planets, 2018
J. T. Wilson, D. J. Lawrence, P. N. Peplowski, J. T. S. Cahill, V. R. Eke, R. J. Massey, L. F. A. Teodoro, (2018), Image Reconstruction Techniques in Neutron and Gamma Ray Spectroscopy: improving Lunar Prospector Data, Journal of Geophysical Research-Planets, 123, 1804-1822

Distal ejecta from lunar impacts: Extensive regions of rocky deposits

Icarus, 2017
Joshua L. Bandfield, Joshua T. S. Cahill, Lynn M. Carter, Catherine D. Neish, G. Wesley Patterson, Jean-Pierre Williams, David A. Paige, (2017), Distal ejecta from lunar impacts: Extensive regions of rocky deposits, Icarus, 283, 282-299

Bistatic radar observations of the Moon using Mini-RF on LRO and the Arecibo Observatory

Icarus, 2017
G. W. Patterson, A. M. Stickle, F. S. Turner, J. R. Jensen, D. B. J. Bussey, P. Spudis, R. C. Espiritu, R. C. Schulze, D. A. Yocky, D. E. Wahl, M. Zimmerman, J. T. S. Cahill, M. Nolan, L. Carter, C. D. Neish, R. K. Raney, B. J. Thomson, R. Kirk, T. W. Thompson, B. L. Tise, I. A. Erteza, C. V. Jakowatz, (2017), Bistatic radar observations of the Moon using Mini-RF on LRO and the Arecibo Observatory, Icarus, 283, 2-19

The compositional and physical properties of localized lunar pyroclastic deposits

Icarus, 2017
David Trang, Jeffrey J. Gillis-Davis, Myriam Lemelin, Joshua T. S. Cahill, B. Ray Hawke, Thomas A. Giguere, (2017), The compositional and physical properties of localized lunar pyroclastic deposits, Icarus, 283, 232-253

Regional spectrophotometric properties of 951 Gaspra

Icarus, 2016
Deborah L. Domingue, Faith Vilas, Teck Choo, Karen R. Stockstill-Cahill, Joshua T. S. Cahill, Amanda R. Hendrix, (2016), Regional spectrophotometric properties of 951 Gaspra, Icarus, 280, 340-358

Origin of the anomalously rocky appearance of Tsiolkovskiy crater

Icarus, 2016
Benjamin T. Greenhagen, Catherine D. Neish, Jean-Pierre Williams, Joshua T. S. Cahill, Rebecca R. Ghent, Paul O. Hayne, Samuel J. Lawrence, Noah E. Petro, Joshua L. Bandfield, (2016), Origin of the anomalously rocky appearance of Tsiolkovskiy crater, Icarus, 273, 237-247

Lunar swirls: Far-UV characteristics

Icarus, 2016
A. R. Hendrix, T. K. Greathouse, K. D. Retherford, K. E. Mandt, G. R. Gladstone, D. E. Kaufmann, D. M. Hurley, P. D. Feldman, W. R. Pryor, S. A. Stern, J. T. S. Cahill, (2016), Lunar swirls: Far-UV characteristics, Icarus, 273, 68-74

Mini-RF and LROC observations of mare crater layering relationships

Icarus, 2016
A. M. Stickle, G. W. Patterson, J. T. S. Cahill, D. B. J. Bussey, (2016), Mini-RF and LROC observations of mare crater layering relationships, Icarus, 273, 224-236

Surveying the South Pole-Aitken basin magnetic anomaly for remnant impactor metallic iron

Icarus, 2014
Joshua T. S. Cahill, Justin J. Hagerty, David J. Lawrence, Rachel L. Klima, David T. Blewett, (2014), Surveying the South Pole-Aitken basin magnetic anomaly for remnant impactor metallic iron, Icarus, 243, 27-30

The Miniature Radio Frequency instrument's (Mini-RF) global observations of Earth's Moon

Icarus, 2014
Joshua T. S. Cahill, B. J. Thomson, G. Wesley Patterson, D. Benjamin J. Bussey, Catherine D. Neish, Norberto R. Lopez, F. Scott Turner, T. Aldridge, M. McAdam, H. M. Meyer, R. K. Raney, L. M. Carter, P. D. Spudis, H. Hiesinger, J. H. Pasckert, (2014), The Miniature Radio Frequency instrument's (Mini-RF) global observations of Earth's Moon, Icarus, 243, 173-190

The relationship between radar scattering and surface roughness of lunar volcanic features

Journal of Geophysical Research-Planets, 2014
Erica R. Jawin, Walter S. Kiefer, Caleb I. Fassett, D. Benjamin J. Bussey, Joshua T. S. Cahill, M. Darby Dyar, Samuel J. Lawrence, Paul D. Spudis, (2014), The relationship between radar scattering and surface roughness of lunar volcanic features, Journal of Geophysical Research-Planets, 119, 2331-2348

The global albedo of the Moon at 1064 nm from LOLA

Journal of Geophysical Research-Planets, 2014
P. G. Lucey, G. A. Neumann, M. A. Riner, E. Mazarico, D. E. Smith, M. T. Zuber, D. A. Paige, D. B. Bussey, J. T. Cahill, A. McGovern, P. Isaacson, L. M. Corley, M. H. Torrence, H. J. Melosh, J. W. Head, E. Song, (2014), The global albedo of the Moon at 1064 nm from LOLA, Journal of Geophysical Research-Planets, 119, 1665-1679

Global distribution of lunar impact melt flows

Icarus, 2014
C. D. Neish, J. Madden, L. M. Carter, B. R. Hawke, T. Giguere, V. J. Bray, G. R. Osinski, J. T. S. Cahill, (2014), Global distribution of lunar impact melt flows, Icarus, 239, 105-117

Spectra of the Wells lunar glass simulants: New old data for reflectance modeling

Journal of Geophysical Research-Planets, 2014
Karen R. Stockstill-Cahill, David T. Blewett, Joshua T. S. Cahill, Brett W. Denevi, Samuel J. Lawrence, Ecaterina I. Coman, (2014), Spectra of the Wells lunar glass simulants: New old data for reflectance modeling, Journal of Geophysical Research-Planets, 119, 925-940

Remote detection of magmatic water in Bullialdus Crater on the Moon

Nature Geoscience, 2013
R. Klima, J. Cahill, J. Hagerty, D. Lawrence, (2013), Remote detection of magmatic water in Bullialdus Crater on the Moon, Nature Geoscience, 6, 737-741

LRO observations of morphology and surface roughness of volcanic cones and lobate lava flows in the Marius Hills

Journal of Geophysical Research-Planets, 2013
Samuel J. Lawrence, Julie D. Stopar, B. Ray Hawke, Benjamin T. Greenhagen, Joshua T. S. Cahill, Joshua L. Bandfield, Bradley L. Jolliff, Brett W. Denevi, Mark S. Robinson, Timothy D. Glotch, D. Benjamin J. Bussey, Paul D. Spudis, Thomas A. Giguere, W. Brent Garry, (2013), LRO observations of morphology and surface roughness of volcanic cones and lobate lava flows in the Marius Hills, Journal of Geophysical Research-Planets, 118, 615-634

Mapping and characterization of non-polar permanent shadows on the lunar surface

Icarus, 2013
J. Andrew McGovern, D. Benjamin Bussey, Benjamin T. Greenhagen, David A. Paige, Joshua T. S. Cahill, Paul D. Spudis, (2013), Mapping and characterization of non-polar permanent shadows on the lunar surface, Icarus, 223, 566-581

A comparison of rayed craters on the moon and mercury

Journal of Geophysical Research-Planets, 2013
C. D. Neish, D. T. Blewett, J. K. Harmon, E. I. Coman, J. T. S. Cahill, C. M. Ernst, (2013), A comparison of rayed craters on the moon and mercury, Journal of Geophysical Research-Planets, 118, 2247-2261

Evidence for water ice on the moon: Results for anomalous polar craters from the LRO Mini-RF imaging radar

Journal of Geophysical Research-Planets, 2013
P. D. Spudis, D. B. J. Bussey, S. M. Baloga, J. T. S. Cahill, L. S. Glaze, G. W. Patterson, R. K. Raney, T. W. Thompson, B. J. Thomson, E. A. Ustinov, (2013), Evidence for water ice on the moon: Results for anomalous polar craters from the LRO Mini-RF imaging radar, Journal of Geophysical Research-Planets, 118, 2016-2029

Near-infrared optical constants of naturally occurring olivine and synthetic pyroxene as a function of mineral composition

Journal of Geophysical Research-Planets, 2013
David Trang, Paul G. Lucey, Jeffrey J. Gillis-Davis, Joshua T. S. Cahill, Rachel L. Klima, Peter J. Isaacson, (2013), Near-infrared optical constants of naturally occurring olivine and synthetic pyroxene as a function of mineral composition, Journal of Geophysical Research-Planets, 118, 708-732

Dating small fresh lunar craters with Mini-RF radar observations of ejecta blankets

Journal of Geophysical Research-Planets, 2012
Samuel W. Bell, Bradley J. Thomson, M. Darby Dyar, Catherine D. Neish, Joshua T. S. Cahill, D. B. J. Bussey, (2012), Dating small fresh lunar craters with Mini-RF radar observations of ejecta blankets, Journal of Geophysical Research-Planets, 117

Oxidation of iron metal and implications for laboratory and remotely sensed spectra of planetary materials

Meteoritics & Planetary Science, 2012
David T. Blewett, Joshua T. S. Cahill, Nhan V. Nguyen, Samuel J. Lawrence, Brett W. Denevi, Ecaterina I. Coman, (2012), Oxidation of iron metal and implications for laboratory and remotely sensed spectra of planetary materials, Meteoritics & Planetary Science, 47, A75-A75

Global catalogue of lunar permanently shadowed regions

Meteoritics & Planetary Science, 2012
D. B. J. Bussey, J. A. McGovern, B. T. Greenhagen, D. A. Paige, J. T. S. Cahill, M. Siegler, P. D. Spudis, (2012), Global catalogue of lunar permanently shadowed regions, Meteoritics & Planetary Science, 47, A90-A90

Exploring for ice with bistatic radar observations of the Moon using the Arecibo Observatory and the Mini-RF Instrument on LRO

Meteoritics & Planetary Science, 2012
D. B. J. Bussey, R. Schulze, D. E. Wahl, M. Nolan, R. Jensen, G. W. Patterson, F. S. Turner, D. A. Yocky, J. T. S. Cahill, R. K. Raney, C. Neish, P. D. Spudis, C. V. Jakowatz, Mini-RF Team, (2012), Exploring for ice with bistatic radar observations of the Moon using the Arecibo Observatory and the Mini-RF Instrument on LRO, Meteoritics & Planetary Science, 47, A91-A91

Determination of iron metal optical constants: Implications for ultraviolet, visible, and near-infrared remote sensing of airless bodies

Geophysical Research Letters, 2012
Joshua T. S. Cahill, David T. Blewett, N. V. Nguyen, Kun Xu, Oleg A. Kirillov, Samuel J. Lawrence, Brett W. Denevi, Ecaterina I. Coman, (2012), Determination of iron metal optical constants: Implications for ultraviolet, visible, and near-infrared remote sensing of airless bodies, Geophysical Research Letters, 39

Initial observations of lunar impact melts and ejecta flows with the Mini-RF radar

Journal of Geophysical Research-Planets, 2012
Lynn M. Carter, Catherine D. Neish, D. B. J. Bussey, Paul D. Spudis, G. Wesley Patterson, Joshua T. Cahill, R. Keith Raney, (2012), Initial observations of lunar impact melts and ejecta flows with the Mini-RF radar, Journal of Geophysical Research-Planets, 117

Characterisation of potential landing sites for the European Space Agency's Lunar Lander project

Planetary and Space Science, 2012
Diego De Rosa, Ben Bussey, Joshua T. Cahill, Tobias Lutz, Ian A. Crawford, Terence Hackwill, Stephan van Gasselt, Gerhard Neukum, Lars Witte, Andy McGovern, Peter M. Grindrod, James D. Carpenter, (2012), Characterisation of potential landing sites for the European Space Agency's Lunar Lander project, Planetary and Space Science, 74, 224-246

The m-chi decomposition of hybrid dual-polarimetric radar data with application to lunar craters

Journal of Geophysical Research-Planets, 2012
R. Keith Raney, Joshua T. S. Cahill, G. Wesley Patterson, D. Benjamin J. Bussey, (2012), The m-chi decomposition of hybrid dual-polarimetric radar data with application to lunar craters, Journal of Geophysical Research-Planets, 117

The m-chi decomposition of hybrid dual-polarimetric radar data

2012 Ieee International Geoscience and Remote Sensing Symposium (Igarss), 2012
R. Keith Raney, Joshua T. S. Cahill, G. Wesley Patterson, D. Benjamin J. Bussey, IEEE, (2012), The m-chi decomposition of hybrid dual-polarimetric radar data, 2012 Ieee International Geoscience and Remote Sensing Symposium (Igarss), 5093-5096

An upper limit for ice in Shackleton crater as revealed by LRO Mini-RF orbital radar

Geophysical Research Letters, 2012
B. J. Thomson, D. B. J. Bussey, C. D. Neish, J. T. S. Cahill, E. Heggy, R. L. Kirk, G. W. Patterson, R. K. Raney, P. D. Spudis, T. W. Thompson, E. A. Ustinov, (2012), An upper limit for ice in Shackleton crater as revealed by LRO Mini-RF orbital radar, Geophysical Research Letters, 39

Radiative transfer modeling of near-infrared reflectance of lunar highland and mare soils

Journal of Geophysical Research-Planets, 2010
J. T. S. Cahill, P. G. Lucey, K. R. Stockstill-Cahill, B. R. Hawke, (2010), Radiative transfer modeling of near-infrared reflectance of lunar highland and mare soils, Journal of Geophysical Research-Planets, 115

Compositional variations of the lunar crust: Results from radiative transfer modeling of central peak spectra

Journal of Geophysical Research-Planets, 2009
J. T. S. Cahill, P. G. Lucey, M. A. Wieczorek, (2009), Compositional variations of the lunar crust: Results from radiative transfer modeling of central peak spectra, Journal of Geophysical Research-Planets, 114

Composition and origin of the Dewar geochemical anomaly

Journal of Geophysical Research-Planets, 2008
Samuel J. Lawrence, B. Ray Hawke, Jeffrey J. Gillis-Davis, G. Jeffrey Taylor, David J. Lawrence, Joshua T. Cahill, Justin J. Hagerty, Paul G. Lucey, Gregory A. Smith, Klaus Keil, (2008), Composition and origin of the Dewar geochemical anomaly, Journal of Geophysical Research-Planets, 113

Radiative transfer modeling of lunar highlands spectral classes and relationship to lunar samples

Journal of Geophysical Research-Planets, 2007
J. T. Cahill, P. G. Lucey, (2007), Radiative transfer modeling of lunar highlands spectral classes and relationship to lunar samples, Journal of Geophysical Research-Planets, 112

Petrogenesis of lunar highlands meteorites: Dhofar 025, Dhofar 081, Dar al Gani 262, and Dar al Gani 400

Meteoritics & Planetary Science, 2004
JT Cahill, C Floss, M Anand, LA Taylor, MA Nazarov, BA Cohen, (2004), Petrogenesis of lunar highlands meteorites: Dhofar 025, Dhofar 081, Dar al Gani 262, and Dar al Gani 400, Meteoritics & Planetary Science, 39, 503-529

An exercise in traceability: Quantifying imaging spectrometer noise constraints on geologic interpretation

Instruments, Science, and Methods For Geospace and Planetary Remote Sensing, 2004
D Steutel, JT Cahill, PG Lucey, CA Nardell, JH Yee, JB Garvin, (2004), An exercise in traceability: Quantifying imaging spectrometer noise constraints on geologic interpretation, Instruments, Science, and Methods For Geospace and Planetary Remote Sensing, 5660, 181-190

Nonmetabolic reduction of Cr(VI) by bacterial surfaces under nutrient-absent conditions

Geomicrobiology Journal, 2002
JB Fein, DA Fowle, J Cahill, K Kemner, M Boyanov, B Bunker, (2002), Nonmetabolic reduction of Cr(VI) by bacterial surfaces under nutrient-absent conditions, Geomicrobiology Journal, 19, 369-382

Martian meteorite Dhofar 019: A new shergottite

Meteoritics & Planetary Science, 2002
LA Taylor, MA Nazarov, CK Shearer, HY McSween, J Cahill, CR Neal, MA Ivanova, LD Barsukova, RC Lentz, RN Clayton, TK Mayeda, (2002), Martian meteorite Dhofar 019: A new shergottite, Meteoritics & Planetary Science, 37, 1107-1128