المؤلفون: Webster, C. R, May, R. D, Allen, M, Jaegle, L, McCormick, M. P

مصطلحات موضوعية: Meteorology And Climatology

الوصف: Simultaneous in situ measurements of stratospheric NO(sub 2), HNO(sub 3), HCI, and CH(sub 4) from 34 to 24 km were made in August 1992 from Palestine, Texas, using the Balloon-borne Laser In-Situ Sensor (BLISS)tunable diode laser spectrometer.

الوصول الحر: https://ntrs.nasa.gov/citations/20060039675Test

المؤلفون: Pyle, J. A, Webster, C. R, May, R. D, Lary, D. J

المصدر: Geophysical Research Letters. 18

مصطلحات موضوعية: Geophysics

الوصف: The present study compares the diurnal variation of NO2 measured near 30 km by the BLISS in situ laser spectrometer with calculations from a photochemical model that includes a detailed description of multiple scattering. Even better agreement is found between the data and the model, both at sunset and during the day. The conclusions of an earlier study that the high-resolution in situ measurements of NO2 facilitated validation of the understanding of the diurnal chemistry of NO2 are confirmed.

الوصول الحر: https://ntrs.nasa.gov/citations/19920036887Test

المؤلفون: Toumi, R, Pyle, J. A, Webster, C. R, May, R. D

المصدر: Geophysical Research Letters. 18

مصطلحات موضوعية: Geophysics

الوصف: Recent measurements by Webster et al. (1990) have confirmed quantitatively the chemistry controlling the nighttime decay of NO2. Simple equations describing the nighttime behavior of NO2 and N2O5 are presented here. With measurements of the nighttime ozone and NO2 concentrations, these equations can be used to predict the amount of N2O5 produced at any time during the night. In this way, the N2O5 nighttime emission measurement of Roscoe (1982), Kunde et al. (1988) and sunrise measurements of the ATMOS experiment are all used to test theory. The measurements are found to be both self consistent and confirm the present understanding of nighttime NO2 conversion to N2O5. The variation of N2O5 by a factor of two between measurements is found to be consistent with theory.

الوصول الحر: https://ntrs.nasa.gov/citations/19910059789Test

المؤلفون: Webster, C. R, May, R. D

المصدر: In: Infrared technology XVII; Proceedings of the Meeting, San Diego, CA, July 22-26, 1991 (A93-38376 15-35).

مصطلحات موضوعية: Instrumentation And Photography

الوصف: The ALIAS instrument is a very high resolution (0.0003/cm) scanning, tunable diode laser spectrometer designed to make direct, simultaneous measurements of NO2, HNO3, HCl, CH4, and either O3 or N2O (including vertical profiles of CH4 and N2O) in the polar stratosphere at sub-part-per-billion level sensitivities over integration times from 3 to 30 s. Unique features include a sample inlet/throttle system designed to achieve near-isokinetic sampling, in PSC events, an in-flight wavelength reference cell rack, mechanical fringe-spoilers, a four-laser/four-detector dewar with 24-hr hold-time operating at a fixed temperature without electrical regulation, and in-flight fast correlation routines for spectral drift compensation prior to spectral addition. Instrument design and test flight results are discussed in the light of ALIAS's role in the Winter 1991 Arctic aircraft stratospheric ozone campaigns out of Fairbanks, Alaska, and Bangor, Maine.

العلاقة: Infrared technology XVII; Proceedings of the Meeting, San Diego, CA, July 22-26, 1991

الوصول الحر: https://ntrs.nasa.gov/citations/19930054399Test

المؤلفون: May, R. D, Webster, C. R

المصدر: Geophysical Research Letters. 17

مصطلحات موضوعية: Geophysics

الوصف: Tunable diode laser laboratory measurements of infrared spectral parameters of selected NO2 lines near 1600/cm have been made to assess the contribution of uncertainties in these parameters to stratospheric measurements of NO2 made using the Balloon-Borne Laser In-Situ Sensor (BLISS) tunable diode laser spectrometer. Relative line intensities are measured to accuracies of better than 2 percent, with a root-sum-squared uncertainty in the absolute linestrengths of 4.5 percent. Air-broadening coefficients have been determined from measurements at total pressures in the range 20-100 Torr, at temperatures of 293 K and 214 K. These results are also discussed in the light of the discrepancies between infrared instruments flown in the 1982 and 1983 Balloon Intercomparison Campaigns.

الوصول الحر: https://ntrs.nasa.gov/citations/19910031761Test

المؤلفون: Jones, J. H., Niles, P. B., Webster, C. R., Mahaffy, P. R., Flesch, G. J., Christensen, L. E., Leshin, L. A., Franz, H., Wong, M., Atreya, S. K., Conrad, P. G., Manning, H., Navarro-Gonzalez, R., Owen, T., Pepin, B., Stern, J. C., Trainer, M., Schwenzer, S. P., the MSL Science Team

العلاقة: Jones, J. H.; Niles, P. B.; Webster, C. R.; Mahaffy, P. R.; Flesch, G. J.; Christensen, L. E.; Leshin, L. A.; Franz, H.; Wong, M.; Atreya, S. K.; Conrad, P. G.; Manning, H.; Navarro-Gonzalez, R.; Owen, T.; Pepin, B.; Stern, J. C.; Trainer, M.; Schwenzer, S. P. and the MSL Science Team (2013). Preliminary interpretations of atmospheric stable isotopes and argon from Mars Science Laboratory (SAM). In: 44th Lunar and Planetary Science Conference, 18-22 Mar 2013, The Woodlands, TX, USA.

الإتاحة: https://oro.open.ac.uk/37356Test/
http://www.lpi.usra.edu/meetings/lpsc2013Test/

المؤلفون: Vasudev, R., Mansour, K., Webster, C. R.

المصدر: 2013 IEEE Aerospace Conference

الإتاحة: https://doi.org/10.1109/aero.2013.6497131Test
http://xplorestaging.ieee.org/ielx7/6490096/6496810/06497131.pdf?arnumber=6497131Test

المؤلفون: Mahaffy, Paul R., Cabane, Michel, Coll, Patrice, Webster, C. R., Conrad, P. G.

المساهمون: NASA Goddard Space Flight Center (GSFC), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH)

المصدر: American Astronomical Society, 41st annual meeting of the Division for Planetary Sciences ; https://hal.science/hal-04113584Test ; American Astronomical Society, 41st annual meeting of the Division for Planetary Sciences, Oct 2009, Fajardo (Porto-Rico), Puerto Rico. pp.id.45.06

مصطلحات موضوعية: [SDU]Sciences of the Universe [physics]

جغرافية الموضوع: Fajardo (Porto-Rico), Puerto Rico

الوقت: Fajardo (Porto-Rico), Puerto Rico

الوصف: International audience ; The 2011 Mars Science Laboratory (MSL) is designed to quantitatively assess a local region on Mars as a potential habitat for present or past life. With a substantially more comprehensive measurement capability that any other Mars rover, to date, its science goals are (1) to assess past or present biological potential of a target environment, (2) to characterize geology and geochemistry at the MSL landing site, and (3) to investigate planetary processes that influence habitability. The Sample Analysis at Mars (SAM) Suite consists of a gas chromatograph (GC), a mass spectrometer (MS), and a tunable laser spectrometer (TLS) and supporting sample manipulation and gas processing systems. SAM will implement a sensitive search for organic molecules and carry out chemical and isotopic analysis of martian volatiles while MSL contact and remote surface and subsurface survey instruments establish geological context. Mineralogy measurements are made by a companion XRD/XRF instrument in the MSL Analytical Laboratory on identically processed samples. SAM is designed to analyze either the atmospheric composition or gases extracted from solid phase samples such as rocks and fines. For example, one of the core SAM experiment sequences heats a small powdered sample of a Mars rock or soil from ambient to 1300 K in a controlled manner while continuously monitoring evolved gases. This is followed by GCMS analysis of organics which have been trapped out of the gas stream. The general chemical survey is enhanced by a specific search for molecular classes that may be relevant to life including atmospheric methane and its carbon isotope with the TLS and complex organics with the GCMS.

العلاقة: hal-04113584; https://hal.science/hal-04113584Test; BIBCODE: 2009DPS.41.4506M

الإتاحة: https://hal.science/hal-04113584Test

المؤلفون: Farley, K. A., Malespin, C., Mahaffy, P., Grotzinger, J. P., Vasconcelos, P. M., Milliken, R. E., Malin, M., Edgett, K. S., Pavlov, A. A., Hurowitz, JA, Grant, John A., Miller, H. B., Arvidson, R., Beegle, L., Calef, F., Conrad, P. G., Dietrich, W. E., Eigenbrode, J., Gellert, R., Gupta, S., Hamilton, V., Hassler, D. M., Lewis, K. W., McLennan, S. M., Ming, D., Navarro-Gonzalez, R., Schwenzer, S. P., Steele, A., Stolper, E. M., Sumner, D. Y., Vaniman, D., Vasavada, A., Williford, K., Wimmer-Schweingruber, R., Blake, D. F., Bristow, T., DesMarais, D., Edwards, L., Haberle, R., Hoehler, T., Hollingsworth, J., Kahre, M., Keely, L., McKay, C., Wilhelm, M. B., Bleacher, L., Brinckerhoff, W., Choi, D., Dworkin, J. P., Floyd, M., Freissinet, C., Garvin, J., Glavin, D., Harpold, D., Martin, D. K., McAdam, A., Raaen, E., Smith, M. D., Stern, J., Tan, F., Trainer, M., Meyer, M., Posner, A., Voytek, M., Anderson, R. C., Aubrey, A., Behar, A., Blaney, D., Brinza, D., Christensen, L., Crisp, J. A., DeFlores, L., Feldman, J., Feldman, S., Flesch, G., Hurowitz, J., Jun, I., Keymeulen, D., Maki, J., Mischna, M., Morookian, J. M., Parker, T., Pavri, B., Schoppers, M., Sengstacken, A., Simmonds, J. J., Spanovich, N., Juarez, M., Webster, C. R., Yen, A., Archer, P. D., Cucinotta, F., Jones, J. H., Morris, R. V., Niles, P., Rampe, E., Nolan, T., Fisk, M., Radziemski, L., Barraclough, B., Bender, S., Berman, D., Dobrea, E. N., Tokar, R., Williams, R. M. E., Yingst, A., Leshin, L., Cleghorn, T., Huntress, W., Manhes, G., Hudgins, J., Olson, T., Stewart, N., Sarrazin, P., Vicenzi, Edward P., Wilson, Sharon A., Bullock, M., Ehresmann, B., Peterson, J., Rafkin, S., Zeitlin, C., Fedosov, F., Golovin, D., Karpushkina, N., Kozyrev, A., Litvak, M., Malakhov, A., Mitrofanov, I., Mokrousov, M., Nikiforov, S., Prokhorov, V., Sanin, A., Tretyakov, V., Varenikov, A., Vostrukhin, A., Kuzmin, R., Clark, B., Wolff, M., Botta, O., Drake, D., Bean, K., Lemmon, M., Anderson, R. B., Herkenhoff, K., Lee, E. M., Sucharski, R., Hernandez, M. A., Avalos, J. J. B., Ramos, M., Kim, M. H., Plante, I., Muller, J. P., Ewing, R., Boynton, W., Downs, R., Fitzgibbon, M., Harshman, K., Morrison, S., Kortmann, O., Palucis, M., Williams, A., Lugmair, G., Wilson, M. A., Rubin, D., Jakosky, B., Balic-Zunic, T., Frydenvang, J., Jensen, J. K., Kinch, K., Koefoed, A., Madsen, M. B., Stipp, S. L. S., Boyd, N., Campbell, J. L., Perrett, G., Pradler, I., VanBommel, S., Jacob, S., Owen, T., Rowland, S., Savijarvi, H., Boehm, E., Bottcher, S., Burmeister, S., Guo, J., Kohler, J., Garcia, C. M., Mueller-Mellin, R., Bridges, J. C., McConnochie, T., Benna, M., Franz, H., Bower, H., Brunner, A., Blau, H., Boucher, T., Carmosino, M., Atreya, S., Elliott, H., Halleaux, D., Renno, N., Wong, M., Pepin, R., Elliott, B., Spray, J., Thompson, L., Gordon, S., Newsom, H., Ollila, A., Williams, J., Bentz, J., Nealson, K., Popa, R., Kah, L. C., Moersch, J., Tate, C., Day, M., Kocurek, G., Hallet, B., Sletten, R., Francis, R., McCullough, E., Cloutis, E., ten Kate, I. L., Fraeman, A., Scholes, D., Slavney, S., Stein, T., Ward, J., Berger, J., Moores, J. E.

الوصف: NASM ; NASM-CEPS ; Peer-reviewed ; MCI

وصف الملف: application/pdf

العلاقة: Science; Farley, K. A., Malespin, C., Mahaffy, P., Grotzinger, J. P., Vasconcelos, P. M., Milliken, R. E., Malin, M., Edgett, K. S., Pavlov, A. A., Hurowitz, JA, Grant, John A., Miller, H. B., Arvidson, R., Beegle, L., Calef, F., Conrad, P. G., Dietrich, W. E., Eigenbrode, J., Gellert, R., Gupta, S., Hamilton, V., Hassler, D. M., Lewis, K. W., McLennan, S. M., Ming, D. et al. 2014. " In Situ Radiometric and Exposure Age Dating of the Martian Surface ." Science . 343 (6169): https://doi.org/10.1126/science.1247166Test; http://hdl.handle.net/10088/21964Test; 118479

الإتاحة: https://doi.org/10.1126/science.1247166Test
http://hdl.handle.net/10088/21964Test

المؤلفون: Mahaffy, P. R., Webster, C. R., Stern, J. C., Brunner, A. E., Atreya, S. K., Conrad, P. G., Domagal-Goldman, S., Eigenbrode, J. L., Flesch, G. J., Christensen, L. E., Franz, H. B., Freissinet, C., Glavin, D.P., Grotzinger, J. P., Jones, J. H., Leshin, L. A., Malespin, C., McAdam, A.C., Ming, D. W., Navarro-Gonzalez, R., Niles, P. B., Owen, T., Pavlov, A. A., Steele, A., Trainer, M. G., Williford, K. H., Wray, J. J. and the MSL Science Team, DLR Collaborator (MSL Science Team), Reitz G.

مصطلحات موضوعية: Strahlenbiologie

الوصف: The deuterium to hydrogen (D/H) ratio in strongly bound water or hydroxyl groups in ancient martian clays retains the imprint of the water of formation of these minerals. Curiosity’s Sample Analysis at Mars (SAM) experiment measured thermally evolved water and hydrogen gas released between 550°C and 950°C from samples of Hesperian era Gale crater smectite to determine this isotope ratio. The D/H value is 3.0 (±0.2) times the ratio in Standard Mean Ocean Water (SMOW). The D/H ratio in this ~3 billion year old mudstone that is half that of the present martian atmosphere but substantially higher than that expected in very early Mars indicates an extended history of hydrogen escape and desiccation of the planet.

العلاقة: Mahaffy, P. R. und Webster, C. R. und Stern, J. C. und Brunner, A. E. und Atreya, S. K. und Conrad, P. G. und Domagal-Goldman, S. und Eigenbrode, J. L. und Flesch, G. J. und Christensen, L. E. und Franz, H. B. und Freissinet, C. und Glavin, D.P. und Grotzinger, J. P. und Jones, J. H. und Leshin, L. A. und Malespin, C. und McAdam, A.C. und Ming, D. W. und Navarro-Gonzalez, R. und Niles, P. B. und Owen, T. und Pavlov, A. A. und Steele, A. und Trainer, M. G. und Williford, K. H. und Wray, J. J. and the MSL Science Team und DLR Collaborator (MSL Science Team), Reitz G. (2014) The imprint of atmospheric evolution in the D/H of Hesperian clay minerals on Mars. Science. American Association for the Advancement of Science (AAAS). DOI:10.1126/science.1260291 ISSN 0036-8075

الإتاحة: https://doi.org/10.1126/science.1260291Test
http://elib.dlr.de/94269Test/