1,723,932 research outputs found
Richardson, Leon J. an Auguste Grimm (1 Brief)
No full textRICHARDSON, LEON J. AN AUGUSTE GRIMM (1 BRIEF)
Richardson, Leon J. an Auguste Grimm (1 Brief) (Br4308)
Brief 4308 (Br4308
Leon J. Weinberger papers, MSS.1800
No full textAbstract: Correspondence, photocopies of the Torah and other religious documents, scholarly work in English and Hebrew, materials relating to the Judaic Studies series of The University of Alabama Press, and other materials produced and gathered by this University of Alabama professor.Scope and Content Note: The Leon J. Weinberger Papers contain materials created and gathered by this scholar during his time as a professor at The University of Alabama. The collection contains photocopies of the Torah and other religious documents; articles and other publications produced by Dr. Weinberger, written both in English and Hebrew; grant and other funding proposals; incoming and outgoing correspondence from 1983 through 1999; materials relating to his work as the General Editor of the Judaic Studies Series of the University of Alabama Press; materials relating to his work as a manuscript reviewer for the National Endowment for the Humanities; and other materials pertaining to his involvement with numerous aspects of The University of Alabama community including student extracurricular organizations.Biographical/Historical Note: Leon J. Weinberger holds a BA from Clark University, a Masters of Hebrew Literature (MHL) from the Jewish Theological Seminary of America, and a PhD from Brandeis University. He joined the faculty of The University of Alabama, department of Religious Studies, in 1964 and retired in 1999. He served as University Research Professor from 1984-1999 and as the General Editor of the Judaic Studies Series of the University of Alabama Press. Weinberger published twelve books, including Jewish Hymnography: A Literary History, edited thirty-eight, and wrote numerous scholarly articles and book reviews in both English and Hebrew. He is a member of the American Academy of Religion, the Society of Biblical Literature, and the Association for Jewish Studies, of which he has served on the Board of Directors
Leon J. Cole
No full textCole is standing, looking at the camera with his right hand in his pocket and a briefcase under his left arm.Inscriptions on image and/or album page: Front: "#99' / "Leon J Cole" / "'23"Digitized by: MBLWHOI Libraryimage/jpg black and white image reformatted digitalPhotograph
Memories of Terrebonne 123
No full textA recorded interview with Leon J. About, in English, begins at 30:30
In Celebration of Homegoing Services of Leon J. Ussery, Jr.
No full textFuneral program for Leon J. Ussery, Jr., born November 6, 1928 and died January 17, 1995. The funeral was held January 21, 1995 at Mt. Zion First Baptist Church, officiated by Rev. Claude W. Black, Jr. Funeral arrangements were made through Sutton-Sutton Mortuary, Inc., and he was buried in Mt. Pleasant Baptist Church Cemetery in Guadalupe County, Texas
Homegoing Services for Rev. Leon J. Ussery, Sr.; BTA
No full textFuneral program for Rev. Leon J. Ussery, Sr., born December 2, 1892 and died May 2, 1984. The funeral was held May 7, 1984 at St. Paul Baptist Church, officiated by Rev. S. H. Bedford. Funeral arrangements were made through Carter-Taylor-Williams Mortuary, and he was buried in Mt. Pleasant Baptist Church Cemetery in Guadalupe County, Texas
Spectral studies in view of the Hera mission
No full textDidymos is a binary asteroid system composed of (65803) Didymos and its
small satellite, Dimorphos. The NASA’s DART planetary defense mission
demonstrated the possibility of asteroid deflection by changing the Dimorphos
orbit through an artificial impact. Understanding the physical and compositional
characteristics of the target is crucial for analyzing the outcomes of this
impact experiment.
The Hera mission, developed by the European Space Agency (ESA), was
launched in October 2024, to study the Didymos system and to investigate
the aftermath of the DART impact on Dimorphos, assessing any changes to
its orbit and surface characteristics. The mission will gather critical data
regarding the composition and structure of both Didymos and Dimorphos,
providing invaluable insights into the nature of these small solar system bodies.
By enhancing our knowledge of these asteroids, Hera will play a pivotal role in
refining our planetary defense strategies and improving our understanding of
the building blocks of the solar system.
This dissertation aims to conduct spectroscopic studies in preparation
for the Hera mission, with a particular focus on the ASPECT spectrometer.
It begins with the search for meteorite which best reproduce Didymos; this
selection will be very useful in preparation for Didymos studies, in particular to
assess space weathering effects (i.e., solar wind, micrometeoroid bombardments
and cosmic ray effects) and photometric behaviors (i.e., changes in the spectral
shape due to different phase angles of observation) on spectroscopic data. Additionally,
identifying these analogues may assist in calibrating the instruments
aboard the Hera mission. We utilized two online databases of meteorite spectra
along with recent spectra of Didymos captured both before and after the DART
impact. Our initial selection was carried out by comparing the band center
values of the silicate absorption bands, localized at 1 and 2 μm, between Didymos
and the meteorites. In the second selection a four-dimensional parameter
space was defined, where the dimensions corresponded to the band depth and
the slope of the two absorption bands, each normalized to Didymos values. We
then identified the meteorites closest to Didymos within this space. A final
selection took into account multiple spectra of the same meteorite (especially
those from different databases), the match in the Mid Infrared (MIR), and
the comparison with the literature. One of the results of this work is a list of
six meteorites that are the most analogous to the Didymos system. We also
found out that Didymos is most probably mainly composed of L/LL ordinary
chondrites, with a preference for the LL sub-type. From our list of meteorites,
we were able to estimate the normalized abundance of olivine and pyroxene
of Didymos. Finally, a match between Didymos and OC meteorites was also
found in the Mid-InfraRed (MIR) range.
Another goal of this thesis is the definition of new spectra parameters to
maximize the scientific return from the ASPECT spectrometer on board Hera,
by inferring the Didymos system composition of the olivine and pyroxene
relative abundance (olv/(olv +pyx)). ASPECT data range from the visible up
to shortwave infrared (SWIR) wavelengths (650-2500 nm) using four different
channels. The SWIR channel, being a single-pixel channel, has a much lower
spatial resolution than the other three channels. Consequently, for the highestresolution
mapping of the Didymos surface, we concentrated on the first three
channels (650–1600 nm). So, new spectral parameters should be defined
within this limited spectral range. For this reason, we first analyzed spectral
parameters over a broader range commonly used in the literature to determine
the composition of S-type asteroids. We then developed new methods specific to
the ASPECT instrument’s spectral range to determine the mineral composition
of Didymos and, more broadly, of S-type asteroids or other type of asteroids
with a silicate surface (such as Vesta). These methods were initially established
using binary mineral mixtures, then calibrated and validated with ordinary
chondrite meteorites. To further validate these methods, we applied them to
other asteroids previously visited by spacecraft, Vesta and Itokawa. The result
of this work is a comprehensive analysis procedure, designed for ASPECT data,
that enables a detailed mapping of mineral distributions across the asteroid’s
surface.
Finally, a method to retrieve and study hydroxyl signatures was defined (in
view of the Didymos exploration) and applied to Vesta. We took advantage of
the newly calibrated data of the VIR spectrometer onboard the NASA’s Dawn
mission to characterize spectral features not or weakly detected in previous
studies thanks to the improved signal-to-noise (S/N) ratio for these spectra. The
goals were to confirm, reinforce and characterize the OH distribution on Vesta
by studying the 2.8 μm band and to look for OH combination bands around
2.2–2.4 μm by defining a spectral analysis procedure that could be applied
also to the ASPECT data. The analysis of hydroxyl absorption bands revealed
an anti-correlation between the abundance of hydroxyl-bearing molecules and
surface reflectance, supporting the link between hydroxyl presence and Vesta’s
dark units. This finding reinforces the hypothesis that the dark areas on Vesta
are due to exogenous carbonaceous chondrites, which are often characterized
by hydroxyl-bearing molecules. Otherwise, no 2.2–2.4 μm feature associated
with OH was detected, indicating that it is not related to hydroxyl presence.
Nonetheless, the method developed for investigating this feature will still be
applied to ASPECT data for further analysis of the Didymos asteroid.
In conclusion, this research not only provides critical insights into the
composition and characteristics of Didymos but also establishes methodologies
that can be instrumental in analyzing the data that will be obtained from
the Hera mission. The findings and techniques developed herein serve as a
foundation for enhanced understanding of small solar system bodies and their
roles in planetary science
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