Hello everyone! I am interested in helping clients achieve their goals and dreams through assisting them in developing the most effective college admissions applications possible. As a college professor, I know the value of higher education and I think it is very important to facilitate, promote, and encourage students to strive for success, through hard work, and to make a positive difference in their nation and for the world.
Originally from Davenport, Iowa, in the Midwestern region of the United States, I graduated high school and proceeded to serve in the U.S. Navy for almost five years. I was then able to pursue my higher education goals and I earned two undergraduate degrees, one Master's degree, and one Ph.D. degree. Besides my interests in science, asteroids, the Sun, and astronomy, I am an amateur chef, avid reader, and am interested in national and world politics.
我出生在美国中西部的爱荷华。高中毕业之后我一直美国海军服役。 之后我继续我的学习生涯并最终获得了博士学位。 我的兴趣除了天文科学， 同时我还是一名业余厨艺爱好者， 喜欢阅读，同时我在世界政治经济方面也有所涉猎。
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Rensselaer Polytechnic Institute
Rensselaer Polytechnic Institute
Iowa State University
Iowa State University
Proposal reviewer/panelist/group chief
I have served on a variety of NASA research and analysis review panel that evaluate proposals for federal research funding.
UND Space Studies Observatory
Since 2005, I have renovated and expanded the capabilities of the UND Space Studies Observatory, which features three Internet-controllable telescopes (two 0.4-meter and one 0.25 meter aperture). Our capabilities include the conduct of broadband photometry projects (for asteroids and variable stars), visible-wavelength stellar spectroscopy, and solar imaging.
University of North Dakota
I am a resident faculty member in the Department of Space Studies. I teach primarily astronomy courses at the undergraduate and graduate levels. I conduct research on NIR reflectance spectroscopy of main-belt asteroids and solar physics research that involves the intrinsic rotations of solar flares and their possible associations with solar flares. In addition, I manage, oversee, and operate the UND Space Studies Observatory (http://observatory.space.edu) that includes three Internet-controllable telescopes. The observatory is used for students to learn how to operate telescopes and conduct basic research projects as part of an undergraduate observational astronomy course. The observatory is also available for students who want to conduct thesis and non-thesis research projects.
获奖 & 荣誉
UND Spirit Faculty Achievement Award
University of North Dakota
This award was given for notable contributions to the Department of Space Studies during the past year.
UND Outstanding Graduate or Professional Teaching Award
University of North Dakota
Outstanding Teaching Awards are given to both individual faculty members and departments.
The Individual Outstanding Teaching Awards include the:
Outstanding Undergraduate Teaching Awards (2-3 awards)
Outstanding Graduate or Professional Teaching Award (1 award).
Do you know a professor who you think is an outstanding teacher? What makes them "outstanding"? Do they . . .
teach effectively, inspire enthusiasm for learning, arouse curiosity, and stimulate independent and critical thinking?
set high expectations, help students to meet them and provide worthwhile feedback to students on their learning?
show respect and concern for students, offering them effective and sympathetic guidance?
demonstrate thorough knowledge of their subject matter including recent developments in their field?
organize the course material and present it cogently and imaginatively?
use innovative design and delivery of course content?
have an interest in current and effective approaches to teaching, and a willing to try new ideas?
provide learning opportunities that extend beyond the classroom?
(for graduate/professional awards) effectively guide students in the kinds of research and/or creative activity expected of them as professionals?
(for graduate/professional awards) provide a positive role model for young scholars in the discipline?
These characteristics described many good teachers, but there are other traits as well and teachers may merit an award on various bases. Individual teaching awards honor undergraduate and graduate or professional teachers who meet a high standard. You can best support your candidate for the award by addressing the strongest characteristics of good teaching you believe they possess. When you address these characteristics provide solid evidence and concrete examples to build the strongest case. Think in terms of constructing a clear and persuasive argument for how and why your candidate does what the criteria specifics and therefore is deserving of the award. It helps to avoid vague, generalized statements ("She inspires enthusiasm for learning.") that do not convey in a clear and tangible way how that enthusiasm is inspired. What specifically happens in that teacher's class that builds a desire to learn in students? Give illustrations. Tell a brief story. If you believe the faculty member in question shows respect and concern for students, go beyond making a simple statement to that effect and give concrete evidence: what kinds of behaviors and activities illustrate this attitude? Can you speak to the experience of a particular student or class? What takes place in his or her classroom that clearly conveys that respect?
Phase Angle Effects on 3 μm Absorption Band on Ceres: Implications for Dawn Mission
D Takir, V Reddy, JA Sanchez, L Le Corre, PS Hardersen, A NathuesThe Astrophysical Journal Letters 804 (1), L13
The Dirty Dozen: NIR Spectral and Mineralogical Interpretations for 12 Vp-Type Asteroids as Candidate Vestoids
PS Hardersen, V Reddy, R RobertsLunar and Planetary Science Conference 46, 1775
More chips off of Asteroid (4) Vesta: characterization of eight Vestoids and their HED meteorite analogs.
Paul S. Hardersen, Vishnu Reddy, Amy MainzerIcarus 242, 269-282
Vestoids are generally considered to be fragments from Asteroid (4) Vesta that were ejected by past collisions that document Vesta’s collisional history. Dynamical Vestoids are defined by their spatial proximity with Vesta (Zappala, V., Bendjoya, Ph., Cellino, A., Farinella, P., Froeschle’, C. . Icarus 116, 291–314; Nesvorny, D. . Nesvorny HCM Asteroid Families V2.0. EAR-A-VARGBDET-5-NESVORNYFAM-V2.0. NASA Planetary Data System.). Taxonomic Vestoids are defined as V-type asteroids that have a photometric, visible-wavelength spectral, or other observational relationship with Vesta (Tholen, D.J., 1984. Asteroid Taxonomy from Cluster Analysis of Photometry. Ph.D. Thesis, University of Arizona, Tucson; Bus, S.J., Binzel, R.P. . Icarus 158, 106–145; Carvano, J., Hasselmann, P.H., Lazzaro, D., Mothe’-Diniz, T. . Astron. Astrophys. 510, A43). We define ‘genetic Vestoids’ as V-type asteroids that are probable fragments ejected from (4) Vesta based on the supporting combination of dynamical, near-infrared (NIR) spectral, and taxonomic evidence. NIR reflectance spectroscopy is one of the primary ground-based techniques to constrain an asteroid’s major surface mineralogy (Burns, R.G. [1993a]. Mineralogical Applications of Crystal Field Theory. Cambridge University Press, Cambridge, UK, 551 p). Despite the reasonable likelihood that many dynamical and taxonomic Vestoids likely originate from Vesta, ambiguity exists concerning the fraction of these populations that are from Vesta as compared to the fraction of asteroids that might not be related to Vesta.
Currently, one of the most robust techniques to identify the genetic Vestoid population is through NIR reflectance spectroscopy from ∼0.7 to 2.5 μm. The derivation of spectral band parameters, and the comparison of those band parameters with those from representative samples from the Howardite–Eucrite–Diogenite (HED) meteorite types, allows a direct comparison of their primary mineralogies. Establishing tighter constraints on the genetic Vestoid population will better inform mass estimates for the current population of probable Vestoids, will provide more accurate orbital information of Vestoid migration through time that will assist dynamical models, and will constrain the overall current abundance of basaltic material in the main asteroid belt (Moskovitz, N.A., Jedicke, R., Gaidos, E., Willman, M., Nesvorny, D., Fevig, R. . Icarus 198, 77–90).
This work reports high-quality NIR spectra, and their respective interpretations, for eight Vp-type asteroids, as defined by Carvano et al. (Carvano, J., Hasselmann, P.H., Lazzaro, D., Mothe’-Diniz, T. . Astron. Astrophys. 510, A43), that were observed at the NASA Infrared Telescope Facility on January 14, 2013 UT. They include: (3867) Shiretoko, (5235) Jean-Loup, (5560) Amytis, (6331) 1992 FZ1, (6976) Kanatsu, (17469) 1991 BT, (29796) 1999 CW77, and (30872) 1992 EM17. All eight asteroids exhibit the broad ∼0.9- and ∼1.9-μm mineral absorption features indicative of pyroxene on each asteroid’s surface. Data reduction and analysis via multiple techniques produced consistent results for the derived spectral absorption band centers and average pyroxene surface chemistries for all eight asteroids (Reddy, V., Sanchez, J.A., Nathues, A., Moskovitz, N.A., Li, J.-Y, Cloutis, E.A., Archer, K., Tucker, R.A., Gaffey, M.J., Mann, P.J., Sierks, H., Schade, U. [2012c]. Icarus 217, 153–168; Lindsay, S.S., Emery, J.P., Marchis, F., Enriquez, J., Assafin, M. . A spectroscopic and mineralogic study of multiple asteroid systems. American Astronomical Society, DPS Meeting #45, #112.04; Lindsay, S.S., Marchis, F., Emery, J.P., Enriquez, J.E., Assafin, M. . Icarus, submitted for publication; Gaffey, M.J., Cloutis, E.A., Kelley, M.K., Reed, K.L. . Mineralogy of asteroids. In: Bottke Jr., W.F., Cellino, A., Paolicchi, P., Binzel, R.P. (Eds.), Asteroids III. The University of Arizona Press, Tucson, pp. 183–204; Burbine, T.H., Buchanan, P.C., Dolkar, T., Binzel, R.P. . Met. Planet. Sci. 44, 1331–1341.). (3867) Shiretoko is most consistent with the eucrite meteorites while the remaining seven asteroids are most consistent with the howardite meteorites. The existing evidence suggests that all eight of these Vp-type asteroids are genetic Vestoids that probably originated from Vesta’s surface.
Chromospheric mass motions and intrinsic sunspot rotations for NOAA Active Regions 10484, 10486, and 10488 using ISOON data.
Paul S. Hardersen, K.S. Balasubramaniam, Svetlana ShkolyarThe Astrophysical Journal, 773, 60
This work utilizes Improved Solar Observing Optical Network continuum (630.2 nm) and Hα (656.2 nm) data to: (1) detect and measure intrinsic sunspot rotations occurring in the photosphere and chromosphere, (2) identify and measure chromospheric filament mass motions, and (3) assess any large-scale photospheric and chromospheric mass couplings. Significant results from 2003 October 27-29, using the techniques of Brown et al., indicate significant counter-rotation between the two large sunspots in NOAA AR 10486 on October 29, as well as discrete filament mass motions in NOAA AR 10484 on October 27 that appear to be associated with at least one C-class solar flare.
The M-/X-asteroid menagerie: Results of an NIR spectral survey of 45 main-belt asteroids
Paul S. Hardersen, Ed Cloutis, Vishnu Reddy, Thais Mothe'-Diniz, Joshua EmeryMeteoritics & Planetary Science, 46, Issue 12, 1910-1938
Diagnostic mineral absorption features for pyroxene(s), olivine, phyllosilicates, and hydroxides have been detected in the near-infrared (NIR: approximately 0.75–2.50 μm) spectra for 60% of the Tholen-classified (Tholen 1984, 1989) M-/X-asteroids observed in this study. Nineteen asteroids (42%) exhibit weak Band I (approximately 0.9 μm) ± Band II (approximately 1.9 μm) absorptions, three asteroids (7%) exhibit a weak Band I (approximately 1.05–1.08 μm) olivine absorption, four asteroids (9%) display multiple absorptions suggesting phyllosilicate ± oxide/hydroxide minerals, one (1) asteroid exhibits an S-asteroid type NIR spectrum, and 18 asteroids (40%) are spectrally featureless in the NIR, but have widely varying slopes. Tholen M-asteroids are defined as asteroids exhibiting featureless visible-wavelength (λ) spectra with moderate albedos (Tholen 1989). Tholen X-asteroids are also defined using the same spectral criterion, but without albedo information. Previous work has suggested spectral and mineralogical diversity in the M-asteroid population (Rivkin et al. 1995, 2000; Busarev 2002; Clark et al. 2004; Hardersen et al. 2005; Birlan et al. 2007; Ockert-Bell et al. 2008, 2010; Shepard et al. 2008, 2010; Fornasier et al. 2010). The pyroxene-bearing asteroids are dominated by orthopyroxene with several likely to include higher-Ca clinopyroxene components. Potential meteorite analogs include mesosiderites, CB/CH chondrites, and silicate-bearing NiFe meteorites. The Eos family, olivine-bearing asteroids are most consistent with a CO chondrite analog. The aqueously altered asteroids display multiple, weak absorptions (0.85, 0.92, 0.97, 1.10, 1.40, and 2.30–2.50 μm) indicative of phyllosilicate ± hydroxide minerals. The spectrally featureless asteroids range from metal-rich to metal-poor with meteorite analogs including NiFe meteorites, enstatite chondrites, and stony-iron meteorites.
Reflectance spectra of iron meteorites: Implications for spectral identification of their parent bodies
Ed Cloutis, Paul S. Hardersen, David L. Bish, Daniel T. Bailey, Michael J. Gaffey, Michael A. CraigMeteoritics & Planetary Science, 45, Issue 2,
The 0.35–2.5 μm reflectance spectra of iron meteorite powders and slabs have been studied as a function of composition, surface texture (for slabs), grain size (for powders), and viewing geometry (for powders). Powder spectra are invariably red-sloped over this wavelength interval and have a narrow range of visible albedos (approximately 10–15% at 0.56 μm). Metal (Fe:Ni) compositional variations have no systematic effect on the powder spectra, increasing grain size results in more red-sloped spectra, and changes in viewing geometry have variable effects on overall reflectance and spectral slope. Roughened metal slab spectra have a wider, and higher, range of visible albedos than powders (22–74% at 0.56 μm), and are also red-sloped. Smoother slabs exhibit greater differences from iron meteorite powder spectra, exhibiting wider variations in overall reflectance, spectral slopes, and spectral shapes. No unique spectral parameters exist that allow for powder and slab spectra to be fully separated in all cases. Spectral differences between slabs and powders can be used to constrain possible surface properties, and causes of rotational spectral variations, of M-asteroids. The magnitude of spectral variations between M-asteroids and rotational and spectral variability does not necessarily imply a dramatic change in surface properties, as the differences in albedo and/or spectral slope can be accommodated by modest changes in grain size (for powders), small changes in surface roughness (for slabs), or variations in viewing geometry. Since metal powders exhibit much less spectral variability than slabs, M-asteroid spectral variability requires larger changes in either powder properties or viewing geometry than for slabs for a given degree of spectral variation.
Near-infrared spectral observations and interpretations for S-asteroids 138 Tolosa, 306 Unitas, 346 Hermentaria, and 480 Hansa
Paul S. Hardersen, Michael Gaffey, Ed Cloutis, Paul Abell, Vishnu ReddyIcarus, 181, 94-106
Near-infrared (∼0.7 to ∼2.5 μm) spectra of S-asteroids 138 Tolosa, 306 Unitas, 346 Hermentaria, and 480 Hansa suggest the presence of variable amounts of orthopyroxene ± clinopyroxene ± olivine ± plagioclase feldspar on the surfaces of these asteroids. The spectra of these asteroids were compared to laboratory mineral mixtures of orthopyroxene, clinopyroxene, and olivine [Singer, R.B., 1981. J. Geophys. Res. 86 (B9), 7967–7982; Cloutis, E.A., 1985. Master's thesis]. The band parameters (band centers, band areas) were quantified and temperature-corrected [Moroz et al., 2000. Icarus 147, 79–93; Gaffey et al., 2002. In: Bottke Jr., W.F., Cellino, A., Paolicchi, P., Binzel, R.P. (Eds.), Asteroids III. The University of Arizona Press, Tucson, pp. 183–204]. Each S-asteroid in this paper exhibits an overall spectral shape with band parameters that are inconsistent with ordinary chondrite near-infrared spectra and their inferred mineral abundances and/or pyroxene chemistries. 138 Tolosa displays a complex spectrum with a broad ∼1 μm absorption feature that displays a double Band I minimum, a well-defined absorption at ∼1.3 μm, and a broad, but weak absorption in the ∼2 μm region. Although different interpretations exist, the Tolosa spectrum is most consistent with a ∼60/40 mixture of Type B clinopyroxene and orthopyroxene. Spectra of 306 Unitas suggest a surface with variable amounts of low-Ca pyroxene and olivine. Unitas is located in the S-(IV) and S-(VI) subtype regions in Gaffey et al. [1993. Icarus 106, 573–602]. 346 Hermentaria exhibits a complex, broad Band I absorption feature and a weak Band II feature, which suggests a ∼50/50 mixture of clinopyroxene and orthopyroxene. Hermentaria is classified as an S-(III). Spectra of 480 Hansa suggest a dominant low-Ca pyroxene component with lesser amounts of olivine. Based on these characterizations, these four S-asteroids should not be considered as potential ordinary chondrite parent bodies. Furthermore, these results suggest that these S-asteroids experienced at least partial melting temperatures [T⩾∼950 °C: Gaffey et al., 1993. Icarus 106, 573–602; Keil, K., 2000. Planet. Space Sci. 48, 887–903] during the formation epoch in the early Solar System. Continuing spectroscopic investigations will discern the relative abundance of chondritic and thermally-evolved objects among the S-type asteroids that have survived since the formation epoch ∼4.56 billion years ago.
Near-IR spectral evidence for the presence of iron-poor orthopyroxenes on the surfaces of six M-type asteroids
Paul S. Hardersen, Michael J. Gaffey, Paul AbellIcarus, 175, 141-158
The first verifiable near-infrared absorption features in the ∼0.9-μm spectral region are reported for Asteroids 16 Psyche, 69 Hesperia, 110 Lydia, 125 Liberatrix, 201 Penelope, and 216 Kleopatra. These weak features (∼1–3%) are attributed to orthopyroxenes present on the surfaces of these asteroids. 16 Psyche and 125 Liberatrix have full rotational coverage while 69 Hesperia, 110 Lydia, 201 Penelope, and 216 Kleopatra have ∼75% rotational coverage. Qualitative ∼2-μm absorption features are present, but are very weak (<1%). Absorption band positions suggest relatively low abundances of calcium and iron in the pyroxenes. This indicates relatively reducing redox conditions for these asteroids, their parent bodies, and the nebular regions in which they formed. Four potential interpretations for these asteroids include: (1) they are exposed metallic cores or core fragments of differentiated parent bodies with residual orthopyroxene mantle material, (2) they are the result of a smelting-like reaction that converts olivine to pyroxene and metallic iron in the presence of carbon at high temperatures, (3) they are analogs to the primitive metal-rich Bencubbinite meteorites, or (4) they represent metallic surfaces which have accumulated silicate debris from external sources. Of the two original interpretations for the M-asteroids, the enstatite chondrite interpretation (Chapman and Salisbury, 1973, Icarus 19, 507–522; Gaffey and McCord, 1979, Mineralogical and petrological characterizations of asteroids. In: Gehrels T. (Ed.), Asteroids. Univ. of Arizona Press, Tucson, pp. 688–723) can be eliminated for these asteroids because the pyroxene in enstatite chondrites is iron-free and does not exhibit such absorption features. The iron meteorite interpretation remains valid, but with modification. For M-Asteroids 16 Psyche and 216 Kleopatra, these spectral results combined with previous determinations of high radar albedos indicate that these bodies are most probably exposed core fragments of differentiated bodies. M-Asteroids 69 Hesperia, 110 Lydia, 125 Liberatrix, and 201 Penelope exhibit similar spectral features consistent with exposed core fragments, but radar observations would be needed to confirm a high metal abundance. Observations of M-Asteroids 136 Austria and 325 Heidelberga suggest the absence of absorption features in the ∼0.4- to ∼2.5-μm region within the scatter of the data. Verification of the presence or absence of features across the surfaces of these two asteroids requires full rotational coverage. The interpretations for these “featureless” M-asteroids are not well-constrained, but remain consistent with the iron meteorite and enstatite chondrite interpretations.
Potentially hazardous Asteroid 2007 LE: Compositional link to the black chondrite Rose City and Asteroid (6) Hebe
SK Fieber-Beyer, MJ Gaffey, WF Bottke, PS HardersenIcarus 250, 430-437
Mineralogy of Asteroid 1459 Magnya and implications for its origin
Paul S. Hardersen, Michael Gaffey, Paul AbellIcarus, 167, 170-177
Detailed near-infrared spectral observations of Asteroid 1459 Magnya reveal an asteroid that is primarily composed of pyroxene and plagioclase feldspar, confirming earlier suggestions that Magnya has a basaltic composition. The average Magnya spectrum for March 23, 2002 has a Band I center of 0.926 μm and a Band II center of 1.938 μm. Observations over hours show little variation in band center positions. The feldspar-to-pyroxene ratio is ∼0.6 on Magnya's surface. Comparing Magnya with the spectral parameters from 4 Vesta shows discordant pyroxene chemistries; Magnya's pyroxenes contain ∼10 mol% less Fs than Vesta's pyroxenes. This suggests that Magnya originated from a parent body other than 4 Vesta and that its progenitor formed in a more chemically reduced region of the solar nebula within the asteroid belt.
memphis Jul 12, 2017
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Hongru Apr 24, 2017
战略管理学 留学文书润色 语言润色
Thank you so much. Very punctual and really helps me a lot!
Yang Luo Apr 24, 2017
I am exceedingly thankful for Paul's help
Apr 24, 2017
生物学 一站式申请 / 项目制套餐
Paul is a very efficient and professional instructor who gave feedback timely and detailed. Thanks for his help and I am glad to work with him again.