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Washington, DC, United States

The Catholic University of America is a private university located in Washington, D.C. in the United States. It is a pontifical university of the Catholic Church in the United States and the only institution of higher education founded by the U.S. Catholic bishops. Established in 1887 as a graduate and research center following approval by Pope Leo XIII on Easter Sunday, the university began offering undergraduate education in 1904. The university's campus lies within the Brookland neighborhood, known as "Little Rome", which contains 60 Catholic institutions, including Trinity Washington University and the Dominican House of Studies.It has been called one of the 25 most underrated colleges in America, one of the nation's best colleges by the Princeton Review, one of the best values of any private school in the country by Kiplinger's, "one of the most eco-friendly universities in the country," was awarded the "highest federal recognition an institution can receive" for community service, and has been recommended by the Cardinal Newman Society in The Newman Guide to Choosing a Catholic College.CUA's programs emphasize the liberal arts, professional education, and personal development. The school stays closely connected with the Catholic Church and Catholic organizations. The American Cardinals Dinner is put on by the residential U.S. cardinals each year to raise scholarship funds for CUA. The university has a long history of working with the Knights of Columbus; the university's law school and basilica have dedications to the involvement and support of the Knights.The university has been visited twice by reigning Popes. Pope John Paul II visited on October 7, 1979. On April 16, 2008, Pope Benedict XVI gave an address on Catholic education and academic freedom on campus. Wikipedia.


Burlaga L.F.,NASA | Ness N.F.,Catholic University of America
Astrophysical Journal | Year: 2014

Voyager 1 (V1) has been observing interstellar magnetic fields for more than one year beginning 2012/209, when V1 crossed a current sheet, a "CS0" having the structure of a tangential discontinuity. The inclination of this current sheet is consistent with an interstellar magnetic field B draped on a blunt heliopause. Two other current sheets (sector boundaries) were observed at 2012/167 and 2011/276 with high inclinations (99° ± 10° and 89° ± 10°, respectively). From 2013.0 to 2013.6, the difference between the azimuthal angle λ of B from the Parker spiral angle at the latitude 34.°6 of V1 was λ-λP = 22° ± 3° and the corresponding difference of the elevation angle δ was δ-δP = 23° ± 8°. During 2012, the deviation from the Parker spiral angle was somewhat smaller. The interstellar magnetic field has a "west to east polarity," opposite to the direction of planetary motions. The magnitude of B varied smoothly in the range 0.38-0.59 nT with an average B = 0.486 ± 0.045 after 2012/237.7. The transition from heliosheath to interstellar magnetic fields is related to a "two-step" increase in the cosmic ray intensity observed by V1 from 2012.30 to 2012.65. The first step increase began near the end of an unusual "away-polarity" sector, and it reached a plateau when V1 moved into a "toward-polarity" sector that ended at CS0. The second step increase began slowly after V1 crossed CS0, and it ended abruptly at 2012/237.728. © 2014. The American Astronomical Society. All rights reserved.. Source


Krasnopolsky V.A.,Catholic University of America
Icarus | Year: 2012

The IRTF/CSHELL observations in February 2006 at LS=10° and 63-93°W show ~10ppb of methane at 45°S to 7°N and ~3ppb outside this region that covers the deepest canyon Valles Marineris. Observations in December 2009 at LS=20° and 0-30°W included spectra of the Moon at a similar airmass as a telluric calibrator. A technique for extraction of the martian methane line from a combination of the Mars and Moon spectra has been developed. The observations reveal no methane with an upper limit of 8ppb. The results of both sessions agree with the observations by Mumma et al. (Mumma, M.J. et al. [2009]. Science 323, 1041-1045) at the same season in February 2006 and are smaller than those in the PFS and TES maps. Production and removal of the biological methane on Mars do not significantly change the redox state of the atmosphere and the balance of hydrogen. A search for ethane at 2977cm-1 results in an upper limit of 0.2ppb. However, this limit does not help to establish the origin of methane on Mars. Reanalysis of our search for SO2 using TEXES confirms the recently established upper limit of 0.3ppb. Along with the lack of hot spots and gas vents with endogenic heat sources in the THEMIS observations, the very low upper limit to SO2 on Mars does not favor geological methane that is less abundant than SO2 in the outgassing from the terrestrial planets. © 2011 Elsevier Inc. Source


Brosius J.W.,Catholic University of America
Astrophysical Journal | Year: 2012

With the Coronal Diagnostic Spectrometer operating in rapid cadence (9.8s) stare mode during a C6.6 flare on the solar disk, we observed a sudden brightening of Fe XIX line emission (formed at temperature T 8MK) above the pre-flare noise without a corresponding brightening of emission from ions formed at lower temperatures, including He I (0.01MK), O V (0.25MK), and Si XII (2MK). The sudden brightening persisted as a plateau of Fe XIX intensity that endured more than 11 minutes. The Fe XIX emission at the rise and during the life of the plateau showed no evidence of significant bulk velocity flows, and hence cannot be attributed to chromospheric evaporation. However, the line width showed a significant broadening at the rise of the plateau, corresponding to nonthermal velocities of at least 89kms-1 due to reconnection outflows or turbulence. During the plateau He I, O V, and Si XII brightened at successively later times starting about 3.5 minutes after Fe XIX, which suggests that these brightenings were produced by thermal conduction from the plasma that produced the Fe XIX line emission; however, we cannot rule out the possibility that they were produced by a weak beam of nonthermal particles. We interpret an observed shortening of the O V wavelength for about 1.5 minutes toward the middle of the plateau to indicate new upward motions driven by the flare, as occurs during gentle chromospheric evaporation; relative to a quiescent interval shortly before the flare, the O V upward velocity was around -10kms-1. © 2012. The American Astronomical Society. All rights reserved.. Source


While CO, HCl, and HF, that were considered in the first part of this work, have distinct absorption lines in high-resolution spectra and were detected four decades ago, the lines of HDO, OCS, and SO2 are either very weak or blended by the telluric lines and have not been observed previously by ground-based infrared spectroscopy at the Venus cloud tops. The H2O abundance above the Venus clouds is typically below the detection limit of ground-based IR spectroscopy. However, the large D/H ratio on Venus facilitates observations of HDO. Converted to H2O with D/H≈200, our observations at 2722cm-1 in the Venus afternoon show a H2O mixing ratio of ∼1.2ppm at latitudes between ±40° increasing to ±60° by a factor of 2. The observations in the early morning reveal the H2O mixing ratio that is almost constant at 2.9ppm within latitudes of ±75°. The measured H2O mixing ratios refer to 74km. The observed increase in H2O is explained by the lack of photochemical production of sulfuric acid in the night time. The recent observations at the P-branch of OCS at 4094cm-1 confirm our detection of OCS. Four distributions of OCS along the disk of Venus at various latitudes and local times have been retrieved. Both regular and irregular components are present in the variations of OCS. The observed OCS mixing ratio at 65km varies from ∼0.3 to 9ppb with the mean value of ∼3ppb. The OCS scale height is retrieved from the observed limb darkening and varies from 1 to 4km with a mean value of half the atmospheric scale height. SO2 at the cloud tops has been detected for the first time by means of ground-based infrared spectroscopy. The SO2 lines look irregular in the observed spectra at 2476cm-1. The SO2 abundances are retrieved by fitting by synthetic spectra, and two methods have been applied to determine uncertainties and detection limits in this fitting. The retrieved mean SO2 mixing ratio of 350±50ppb at 72km favors a significant increase in SO2 above the clouds since the period of 1980-1995 that was observed by the SOIR occultations at Venus Express. Scale heights of OCS and SO2 may be similar, and the SO2/OCS ratio is ∼500 and may be rather stable at 65-70km under varying conditions on Venus. © 2010 Elsevier Inc. Source


Long-term MGS drag density observations at 390km reveal variations of the density with season LS (by a factor of 2) and solar activity index F10.7 (by a factor of 3 for F10.7=40-100). According to Forbes et al. (Forbes, J.M., Lemoine, F.G., Bruinsma, S.L., Smith, M.D., Zhang, X. [2008]. Geophys. Res. Lett. 35, L01201, doi:10.1029/2007GL031904), the variation with F10.7 reflects variations of the exospheric temperature from 192 to 284K. However, the derived temperature range corresponds to variation of the density at 390km by a factor of 8, far above the observed factor of 3. The recent thermospheric GCMs agree with the derived temperatures but do not prove their adequacy to the MGS densities at 390km. A model used by Forbes et al. neglects effects of eddy diffusion, chemistry and escape on species densities above 138km. We have made a 1D-model of neutral and ion composition at 80-400km that treats selfconsistently chemistry and transport of species with F10.7, T∞, and [CO2]80km as input parameters. Applying this model to the MGS densities at 390km, we find variation of T∞ from 240 to 280K for F10.7=40 and 100, respectively. The results are compared with other observations and models. Temperatures from some observations and the latest models disagree with the MGS densities at low and mean solar activity. Linear fits to the exospheric temperatures are T∞=122+2.17F10.7 for the observations, T∞=131+1.46F10.7 for the latest models, and T∞=233+0.54F10.7 for the MGS densities at 390km. Maybe the observed MGS densities are overestimated near solar minimum when they are low and difficult to measure. Seasonal variations of Mars' thermosphere corrected for the varying heliocentric distance are mostly due to the density variations in the lower and middle atmosphere and weakly affect thermospheric temperature. Nonthermal escape processes for H, D, H2, HD, and He are calculated for the solar minimum and maximum conditions.Another problem considered here refers to Mars global photochemistry in the lower and middle atmosphere. The models gave too low abundances of CO, smaller by an order of magnitude than those observed. Our current work shows that modifications in the boundary conditions proposed by Zahnle et al. (Zahnle, K., Haberle, R.M., Catling, D.C., Kasting, J.F. [2008]. J. Geophys. Res. 113, E11004, doi:10.1029/2008JE003160) are reasonable but do not help to solve the problem. © 2010 Elsevier Inc. Source

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