R
R. D. Starr
Researcher at The Catholic University of America
Publications - 221
Citations - 7586
R. D. Starr is an academic researcher from The Catholic University of America. The author has contributed to research in topics: Mercury (element) & Mars Exploration Program. The author has an hindex of 39, co-authored 216 publications receiving 6705 citations. Previous affiliations of R. D. Starr include University of Arizona & University of Washington.
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Journal ArticleDOI
Distribution of Hydrogen in the Near-Surface of Mars: Evidence for Subsurface Ice Deposits
William V. Boynton,W. C. Feldman,S. W. Squyres,Thomas H. Prettyman,J. Brückner,Larry G. Evans,R. C. Reedy,R. C. Reedy,R. D. Starr,James R. Arnold,D. M. Drake,P. Englert,Albert E. Metzger,I. G. Mitrofanov,Jacob I. Trombka,Claude d’Uston,Heinrich Wänke,Olivier Gasnault,D. K. Hamara,Daniel M. Janes,Robert L. Marcialis,Sylvestre Maurice,I. Mikheeva,G. J. Taylor,R. L. Tokar,C. Shinohara +25 more
TL;DR: The Gamma-Ray Spectrometer on the Mars Odyssey has identified two regions near the poles that are enriched in hydrogen, and it is suggested that the host of the hydrogen in the subsurface layer is ice, which constitutes 35 ± 15% of the layer by weight.
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The Major-Element Composition of Mercury’s Surface from MESSENGER X-ray Spectrometry
Larry R. Nittler,R. D. Starr,Shoshana Z. Weider,Timothy J. McCoy,William V. Boynton,Denton S. Ebel,Carolyn M. Ernst,Larry G. Evans,John O. Goldsten,D. K. Hamara,David J. Lawrence,Ralph L. McNutt,C. E. Schlemm,Sean C. Solomon,Ann L. Sprague +14 more
TL;DR: X-ray fluorescence spectra obtained by the MESSENGENGER spacecraft orbiting Mercury indicate that the planet's surface differs in composition from those of other terrestrial planets as discussed by the authors, and this observation, together with a low surface Fe abundance, supports the view that Mercury formed from highly reduced precursor materials, perhaps akin to enstatite chondrite meteorites or anhydrous cometary dust particles.
Journal ArticleDOI
The Mars Odyssey Gamma-Ray Spectrometer Instrument Suite
William V. Boynton,W. C. Feldman,I. G. Mitrofanov,Larry G. Evans,Robert C. Reedy,Steven W. Squyres,R. D. Starr,Jacob I. Trombka,Claude d’Uston,James R. Arnold,P. A. J. Englert,Albert E. Metzger,Heinrich Wänke,J. Brückner,D. M. Drake,C. Shinohara,C. Fellows,D. K. Hamara,K. Harshman,K. Kerry,C. Turner,Martin Ward,H. Barthe,K. R. Fuller,S. A. Storms,G. W. Thornton,J. L. Longmire,M. L. Litvak,A. K. Ton'chev +28 more
TL;DR: The Mars Odyssey Gamma-Ray Spectrometer (MOGRS) is a suite of three different instruments, a gamma subsystem (GS), a neutron spectrometer, and a high-energy neutron detector, working together to collect data that will permit the mapping of elemental concentrations on the surface of Mars.
Journal ArticleDOI
Concentration of H, Si, Cl, K, Fe, and Th in the low- and mid-latitude regions of Mars
William V. Boynton,G. J. Taylor,Larry G. Evans,Robert C. Reedy,R. D. Starr,Daniel M. Janes,K. Kerry,D. M. Drake,Kyeong Ja Kim,Kyeong Ja Kim,R. M. S. Williams,M. K. Crombie,James M. Dohm,Victor R. Baker,Albert E. Metzger,Suniti Karunatillake,John Keller,John Keller,Horton E. Newsom,James R. Arnold,J. Brückner,P. A. J. Englert,Olivier Gasnault,Ann L. Sprague,I. G. Mitrofanov,S. W. Squyres,Jacob I. Trombka,L. C. d'Uston,Heinrich Wänke,D. K. Hamara +29 more
TL;DR: The Gamma Ray Spectrometer (GRS) on board the 2001 Mars Odyssey Mission for ±∼45° latitudes was used to determine the concentrations of H, Si, Cl, K, Fe, and Th.
Journal ArticleDOI
Hydrogen mapping of the lunar south pole using the LRO neutron detector experiment LEND.
I. G. Mitrofanov,A. B. Sanin,William V. Boynton,Gordon Chin,James B. Garvin,Dmitry Golovin,Larry G. Evans,K. Harshman,A. S. Kozyrev,Maxim Litvak,Alexey Malakhov,Erwan Mazarico,T. P. McClanahan,G. M. Milikh,Maxim Mokrousov,G. Nandikotkur,Gregory A. Neumann,I. Nuzhdin,R. Z. Sagdeev,V. V. Shevchenko,Valery Shvetsov,David E. Smith,R. D. Starr,Vladislav Tretyakov,J. Trombka,D. Usikov,A. Varenikov,Andrey Vostrukhin,Maria T. Zuber +28 more
TL;DR: The LCROSS impact site inside the Cabeus crater demonstrates the highest hydrogen concentration in the lunar south polar region, corresponding to an estimated content of 0.5 to 4.0% water ice by weight, depending on the thickness of any overlying dry regolith layer.