Saturn's icy satellites investigated by Cassini-VIMS: I. Full-disk properties: 350-5100 nm reflectance spectra and phase curves     

G. Filacchione  F. Capaccioni  A. Coradini  P. Cerroni  F. Tosi  V. Formisano  K.H. Baines  B.J. Buratti  M. Combes  P. Drossart  Y. Langevin  V. Mennella  P.D. Nicholson  C. Sotin  K. Hibbitts  S. Newman 《Icarus》2007,186(1):259-290

Saturn's icy satellites are among the main scientific objectives of the Cassini-VIMS (Visual and Infrared Mapping Spectrometer) experiment. This paper contains a first systematic and comparative analysis of the full-disk spectral properties of Dione, Enceladus, Epimetheus, Hyperion, Iapetus, Mimas, Phoebe, Rhea and Tethys as observed by VIMS from July 2004 to June 2005. The disk integrated properties (350-5100 nm reflectance spectra and phase curves at 550-2232 nm) and images of satellites are reported and discussed in detail together with the observed geometry. In general, the spectra in the visible spectral range are almost featureless and can be classified according to the spectral slopes: from the bluish Enceladus and Phoebe to the redder Iapetus, Hyperion and Epimetheus. In the 1000-1300 nm range the spectra of Enceladus, Tethys, Mimas and Rhea are characterized by a negative slope, consistent with a surface largely dominated by water ice, while the spectra of Iapetus, Hyperion and Phoebe show a considerable reddening pointing out the relevant role played by darkening materials present on the surface. In between these two classes are Dione and Epimetheus, which have a flat spectrum in this range. The main absorption bands identified in the infrared are the 1520, 2020, 3000 nm H₂O/OH bands (for all satellites), although Iapetus dark terrains show mostly a deep 3000 nm band while the 1520 and 2020 nm bands are very faint. In this spectral range, the Iapetus spectrum is characterized by a strong reddening. The CO₂ band at 4260 nm and the Fresnel ice peak around 3100 nm are evident only on Hyperion, Phoebe and Iapetus. The phase curves at 550 and at 2232 nm are reported for all the available observations in the 0°-144° range; Rhea shows an opposition surge at visible wavelengths in the 0.5°-1.17° interval. The improvement on the retrieval of the full-disk reflectance spectra can be appreciated by a direct comparison with ground-based telescopic data available from literature. Finally, data processing strategies and recent upgrades introduced in the VIMS-V calibration pipeline (flat-field and destriping-despiking algorithm) are discussed in appendices.  相似文献   

Seeing how it was?: childhood geographies and memories in home movies     

Heather Norris Nicholson 《Area》2001,33(2):128-140

Home movies provided valuable insights into childhood experiences during much of the twentieth century. Contrasting footage of children in rural and urban setting in Northern England between c.1937 and 1970, viewed through the cinematic gaze of two male amateur film-makers underpins this discussion of childhood geographies in the past. Issues explored in the paper include the social construction of childhood, power relations and visual representation of children, and the role of home movie-making in shaping memories and constituting ideas and ideologies about family and children.  相似文献   

Movements and population structure of Atlantic menhaden indicated by tag returns     

William R. Nicholson 《Estuaries and Coasts》1978,1(3):141-150

Over 968,000 adult Atlantic menhaden,Brevoortia tyrannus, were tagged from 1967 to 1969 and over 85,000 juvenile menhaden were tagged from 1969 to 1973. Recoveries of these tagged fish through 1975 provide direct evidence that Atlantic menhaden consist of a single population that over-winters in offshore waters off the southeastern coast of the United States, moves northward in spring and stratifies along the coast by age and size during summer, and moves southward in late autumn.  相似文献   

At home and abroad with cine enthusiasts: Regional amateur filmmaking and visualizing the Mediterranean, ca. 1928–1962.     

Heather Norris Nicholson 《GeoJournal》2004,59(4):323-333

After the appearance of a portable Kodak cine camera in 1923, home moving making grew steadily in popularity in the years leading up to and following World War II. Cine enthusiasts, particularly in the pre-war period, tended to be male, white and middle class, although exceptions exist, and they tended to travel with their cameras much as earlier generations had documented their experiences in written and artistic form. Despite their amateur status, they were often very professional in their approach to cinematography and they produced material for a range of domestic and public audiences on varied topics and in different genres. Specialist publications and the rapid growth of local amateur film societies fostered the rise of an active non-professional film movement; the result is a highly distinctive although neglected component of film history. With reference to materials held at the North West Film Archives in Manchester, England, this discussion considers the rise of non-professional filmmaking at the regional level during the decades before and after the second world war. Making and showing home movies is placed within various socio-cultural contexts. The imagery discloses much about visual practice, including filmmakers' perceptions and their relationships with different kinds of subject matter. The making of holiday footage, in Mediterranean settings, and its subsequent screening in domestic or public places, connects with broader issues of visualization, social practice and leisure-related consumption. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Three-dimensional empirical traveltimes: construction and applications     

T. Nicholson  M. Sambridge  Ó. Gudmundsson 《Geophysical Journal International》2004,156(2):307-328

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Constraints on earthquake epicentres independent of seismic velocity models   总被引：1，自引：0，他引：1  

T. Nicholson  Ó. Gudmundsson  M. Sambridge 《Geophysical Journal International》2004,156(3):648-654

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The quasi-periodic behavior of rainfall variability in Africa and its relationship to the southern oscillation     

Prof. Dr. Sharon E. Nicholson  Mr. Dara Entekhabi 《Meteorology and Atmospheric Physics》1986,34(3-4):311-348

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Book reviews     

Curt Covey  Sharon E. Nicholson 《Climatic change》1989,14(1):103-107

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Two-micron spectrophotometry of Uranus and its rings     

P.D. Nicholson  T.J. Jones 《Icarus》1980,42(1):54-67

Multiaperture K photometry and 2.0- to 2.5-μm spectrophotometry of Uranus and its ring system are presented. The photometric results are used, together with a previously published measurement, to set limits on the geometric albedos of Uranus and the rings at ～2.2 μm: (0.74 ± 0.02) × 10(su?4) ≤ p_K (Uranus) ≤ (1.5 ± 0.3) × 10^?4, and (2.7 ± 0.6) × 10^?2 ≤ p_K (rings) ≤ (3.4 ± 0.1) × 10^?2. Reflectance spectra of Uranus and Uranus plus rings show features in the planet's spectrum which are attributed to gaseous CH₄ absorption, and a 2.20-μm feature in the combined spectrum which may be due to the rings. This feature is tentatively identified with either the 2.26-μm absorption feature of NH₃ frost, or the 2.2-μm OH band exhibited by certain silicate minerals. The results of JHK photometry of Uranus' satellite, Ariel (U1), indicate that the infrared colors of this object are very similar to those of the satellites U2, U3, and U4.  相似文献   

The use of the Coulter Counter for the Determination of Marine Primary Productivity     

Cushing  D. H.; Nicholson  H. F.; Fox  G. P. 《ICES Journal of Marine Science》1968,32(1):131-151

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