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Outside of self-report surveys, there are no proven, reliable methods to quantify visual discomfort or visually induced motion sickness symptoms when using head-mounted displays. While valuable tools, self-report surveys suffer from potential biases and low sensitivity due to variability in how respondents may assess and report their experience. Consequently, extreme visual-vestibular conflicts are generally used to induce discomfort symptoms large enough to measure reliably with surveys (e.g., stationary participants riding virtual roller coasters). An emerging area of research is the prediction of discomfort survey results from physiological and behavioral markers. However, the signals derived from experimental paradigms that are explicitly designed to be uncomfortable may not generalize to more naturalistic experiences where comfort is prioritized. In this work we introduce a custom VR headset designed to introduce significant near-eye optical distortion (i.e., pupil swim) to induce visual discomfort during more typical VR experiences. We evaluate visual comfort in our headset while users play the popular VR title Job Simulator and show that eye-tracked dynamic distortion correction improves visual comfort in a multi-session, within-subjects user study. We additionally use representational similarity analysis to highlight changes in head and gaze behavior that are potentially more sensitive to visual discomfort than surveys. [ABSTRACT FROM AUTHOR]

As the cloud moves from monolithic infrastructure to a self-isolated cloud native microservice environment, automation is becoming an important aspect for the management of the application life cycle. In this context, there are many tools available that can monitor these applications and raise alarms. However, automated orchestration is still in its early stages, and the available solutions are not capable of monitoring the whole system from application to hardware levels and performing automated operations within the system. Moreover, IP Multimedia Subsystem (IMS), which is the core part of the Telecom industry, has switched to a microservice environment. These IMS services are critical and need to be proactively monitored to provide automated orchestration operations. In this paper, we address the aforementioned problem by proposing a new scheme for monitoring the metrics from different sources and proactively and automatically performing orchestration using machine learning while improving the scalability of the cloud native Virtual IMS. Experiments carried out with a real cloud-native IMS running in a kubernetes cluster explore the relevance, efficiency and scalability of the proposed scheme.

Previous literature suggests that the motion sickness susceptibility questionnaire (MSSQ) is inadequate for prediction of motion sickness under naturalistic driving conditions. In this study, we investigated whether visually induced motion sickness using a virtual reality headset could be used as a quick and reliable way to predict participant susceptibility. We recruited 22 participants to complete a two-part experiment. In randomised order, we determined their susceptibility to visual motion sickness and their susceptibility to car sickness. To determine visual susceptibility, the visual scene was sequentially rotated at constant velocity around an earth-vertical yaw axis and rolled about the nasiooccipital axis, in 30 s intervals. Car sickness, on the other hand, was elicited under completely naturalistic conditions, being driven in the backseat of a car in the city of Delft, performing a visual task on a laptop. Sickness ratings were collected at regular intervals in both parts of the experiment. We found that the frequencies excited by naturalistic driving are very low, which has important consequences for motion sickness modelling and mitigation in automated vehicles. We found that individual car sickness correlated positively with visual motion sickness. This indicates that both are influenced by a common sickness susceptibility factor. Car sickness correlated similarly with visual motion sickness and MSSQ. Overall, our results indicate that combining measurements of sickness responses to a visual stimulus and MSSQ can yield a reliable method for determining individual sickness susceptibility. To this end the visual stimulus and the weighting with MSSQ responses can be refined using a much larger sample and considering additional visual conditions in driving., Competing Interests: Declarations. Conflict Of interest: No conflict of interest exists for any author., (© 2025. The Author(s).)

Visually induced motion sickness (VIMS) is a relevant limiting factor in the use of virtual reality (VR) devices. Understanding the origin of this problem might help to develop strategies to circumvent this limitation. Previous studies have attributed VIMS to a mismatch between visual, and vestibular information, causing ambiguity of the position of the body in relation to its surrounding. Studies using EEG have shown a shift of the power spectrum to lower frequencies while VIMS is experienced. However, little is known about the relationship between the intensity of the VIMS and the changes in these power spectra. Moreover, the effect of different varieties of VIMS on the causal relationship between brain areas is largely unknown. Here, we used EEG to study 14 healthy subjects in a VR environment who were exposed to increasing levels of mismatch between vestibular and visual information. The frequency power and the bivariate transfer entropy as a measure for the information transfer were calculated. We found a direct association between increasing mismatch levels and subjective VIMS. With increasing VIMS, the proportion of slow EEG waves (especially 1–10 Hz) increases, especially in temporo-occipital regions. Furthermore, we found a general decrease in the information flow in most brain areas but especially in brain areas involved in the processing of vestibular signals and the detection of self-motion. We hypothesize that the general shift of frequency power and the decrease in information flow while experiencing high intensity VIMS represent a brain state of a reduced ability to receive, transmit and process information. We further hypothesize that the mechanism of reduced information flow is a general reaction of the brain to an unresolvable mismatch of information. This reaction aims on transforming a currently unstable model with a high prediction error into a stable model in an environment of minimal contradictory information.

Visually induced motion sickness (VIMS) is a relevant limiting factor in the use of virtual reality (VR) devices. Understanding the origin of this problem might help to develop strategies to circumvent this limitation. Previous studies have attributed VIMS to a mismatch between visual, and vestibular information, causing ambiguity of the position of the body in relation to its surrounding. Studies using EEG have shown a shift of the power spectrum to lower frequencies while VIMS is experienced. However, little is known about the relationship between the intensity of the VIMS and the changes in these power spectra. Moreover, the effect of different varieties of VIMS on the causal relationship between brain areas is largely unknown. Here, we used EEG to study 14 healthy subjects in a VR environment who were exposed to increasing levels of mismatch between vestibular and visual information. The frequency power and the bivariate transfer entropy as a measure for the information transfer were calculated. We found a direct association between increasing mismatch levels and subjective VIMS. With increasing VIMS, the proportion of slow EEG waves (especially 1–10 Hz) increases, especially in temporo-occipital regions. Furthermore, we found a general decrease in the information flow in most brain areas but especially in brain areas involved in the processing of vestibular signals and the detection of self-motion. We hypothesize that the general shift of frequency power and the decrease in information flow while experiencing high intensity VIMS represent a brain state of a reduced ability to receive, transmit and process information. We further hypothesize that the mechanism of reduced information flow is a general reaction of the brain to an unresolvable mismatch of information. This reaction aims on transforming a currently unstable model with a high prediction error into a stable model in an environment of minimal contradictory information. [ABSTRACT FROM AUTHOR]

Cybersickness is a known issue in virtual reality affecting a notable percentage of the populations. However, predicting the level and incidence of cybersickness in new systems is difficult. Past publications were analyzed for their factors and resulting cybersickness scores. These factors were then used to develop three predictive models using demographics, software, and hardware factors. Using demographic information alone explained 44.2% of the adjusted variance in a linear model. Using hardware and software factors alone explained 55.3% of the adjusted variance in a linear model. Using demographics, software, and hardware factors did not use a linear model, but rather had an average residual error of 1.03. This residual error is an estimate of how far the predicted cybersickness score is from the actual score. [ABSTRACT FROM AUTHOR]

Abstract: During the Cassini mission the Saturnian moons Dione and Tethys showed intriguing and multiple clues suggesting residual geologic activity that might be detectable as an atmosphere, plume, or even heat signature. These clues included an atmospheric aura around Dione, injection of particles into Saturn's magnetosphere, mysterious red streaks on Tethys, and possible cryovolcanic features on Dione. A concerted effort that was strengthened in the latter stages of the mission included the acquisition of stellar occulations by the Ultraviolet Imaging Spectrograph (UVIS) of both Dione and Tethys and high solar phase observations of Dione by the Visible Infrared Mapping Spectrometer (VIMS) to detect forward scattering from grains in a plume. Analysis of these observations shows no evidence for even a low level of activity on either moon. In addition, infrared images at 2.65 μm obtained throughout the mission were scrutinized for the reappearance of an atmosphere‐like aura, with negative results. [ABSTRACT FROM AUTHOR]

Abstract: Near‐infrared spectral maps of Saturn's north polar vortex obtained at high spatial resolution provided by Cassini/Visual Infrared Mapping Spectrometer (VIMS) reveal localized ammonia clouds composed of unusually large particles exceeding 13 μm in radius, the largest cloud particles documented during the Cassini mission. Taken under near‐optimum direct polar lighting and viewing conditions within a month of the summer solstice, these small (~200 km in breadth) discrete clouds are located within the eye of the polar vortex, which otherwise is unusually clear of observable aerosols in reflected sunlight, with total 2‐μm opacity <0.04 versus >1.0 elsewhere on Saturn. The dichotomy of large‐particle condensate cloud features—indicative of convective upwelling—within a large (~ 2000‐km diameter) nearly aerosol‐free region of downwelling characteristic of the core of a polar vortex reveals surprising polar dynamics on Saturn. [ABSTRACT FROM AUTHOR]

The use of seismic analysis to estimate ground material properties such as bulk modulus, shear modulus or stiffness has been the subject of research in recent decades. In general, the velocity of a generated wave depends on the properties of the ground through which it travels. While in the case of subsurface methods, where the P- and S-wave velocities are measured, surface methods rely on the velocity of surface waves such as Rayleigh waves (Tokimatsu et al. in Soils Found 31(2):153-163, 1991, doi:10.3208/sandf1972.31.2_153; Matthews et al. in Proc ICE-Geotech Eng 119(2):84-95. 1996). The results of previous analyses on passive seismic monitored truck motion on oil sand was collected via an array of 72 geophones spaced at 1 m intervals on an oil sand haul road. This paper describes the principles to determine a ground shear modulus from seismic data. The method applies to stationary envelopes of data filtered to obtain a conclusive comparison. [ABSTRACT FROM AUTHOR]

Background Visually Induced Motion Sickness (VIMS) or simulator sickness is often elicited by a visual stimulus that lacks the appropriate vestibular or proprioceptive feedback. In this study, we chose to investigate the effects of brightness and contrast of the visual scene on VIMS. Hypothesis We hypothesized that visual environments differing in brightness or contrast would differentially induce VIMS. The symptoms of VIMS should be most severe for the combination of high brightness and high contrast and conversely lowest for the low brightness and low contrast condition. Methods 33 healthy subjects were tested in a fixed-base flight simulator. Each subject flew in four consecutive but counterbalanced conditions during one large experimental session. The four conditions consisted of identical recorded flight paths, differing only in brightness and contrast in a fully crossed design. VIMS was assessed with the Simulator Sickness Questionnaire and the Fast Motion Sickness scale administered during and after each condition. Postural Sway (PS) was measured after each condition. Results All four brightness and contrast conditions were found to be effective in that they increased PS and elicited moderate VIMS. However, there were no main or interaction effects for brightness or contrast. Conclusions Our findings suggest that brightness and contrast do not modulate the induction of VIMS. This conclusion may be limited to moderately provocative stimuli. [ABSTRACT FROM AUTHOR]

• Packed media are modeled by radiative transfer with static structure factor, RTT-PM. • Gaussian particles in packed media scheme effectively model icy regolith spectra. • Parameters of the shape of Saturnian moon regolith particles have been found. • The model balances physical rigor with practicality and is promising for large data. The radiative transfer theory with packed media correction (RTT-PM) is a balanced, physically rigorous, and practical light scattering model that is suitable for modeling reflectance and similar spectra of densely packed particulate media. The static structure factor correction to the classical radiative transfer solution and actualization of fundamental particles of media with spheres or aggregates are key properties of this model that ensure both physical rigor and practical efficiency. We improved upon the assumptions in the RTT-PM method by incorporating irregularly shaped Gaussian particles into its scheme. This incorporation of Gaussian particles is a notable advancement for applications of the RTT-PM method to planetary surfaces that often are layers of irregularly shaped particles. With the Gaussian particle RTT-PM method, we modeled spectra of Saturnian moons Dione, Rhea, and Tethys observed with the Cassini Visual and Infrared Mapping Spectrometer (VIMS), assuming pure water ice composition. For Rhea and Tethys, the Gaussian particle RTT-PM technique modeled VIMS spectra better than models with spherical or aggregate particles, strengthening prior suggestion that particles on Rhea and Tethys are solid, non-spherical particles. Dione's spectra were best modeled not with Gaussian particles but rather with an aggregate of 128 monomers. This makes Dione's icy regolith different from that on Rhea and Tethys. Prior studies have indicated that the cause for the difference might arise from the presence of surface macrostructures or absorbing materials on Dione, but according to our modeling results, increased multiple scattering from small fluffy aggregate particles is an alternative explanation. [ABSTRACT FROM AUTHOR]

Abstract: We have processed all images of Titan''s surface acquired by the Visual and Infrared Mapping Spectrometer between 2004 and 2010, with the objective of producing seamless global mosaics of the surface in the six infrared atmospheric windows at 1.08, 1.27, 1.59, 2.03, 2.6–2.7 and 5μm. A systematic study of the photometry at 5μm, where haze scattering can be neglected, shows that the surface behaves to first order like a Lambert surface. The results at 5μm are generalized to lower wavelengths, adding an empirical correction accounting for scattering from atmospheric aerosols, using methane band wings as a proxy for the calculation of the scattering additive term. Mosaics incorporating this empirical correction for the geometry and haze scattering show significantly less seams than any previous maps integrating data acquired over such a wide range of observing geometries, and may therefore be used for the study of surface properties. We provide several suggestions for further studies aimed at improving the global mapping of the surface of Titan. With the considered thresholds limits on the acquisition parameters, we found that 13% of Titan''s surface has been mapped at an instrument resolution better than 10km/pixel, 56% of the surface was seen at a resolution between 10 and 20km/pixel, and 24% of the coverage falls in the range 20–50km/pixel. [Copyright &y& Elsevier]

Abstract: Saturn''s Moon Titan has a thick atmosphere with a meteorological cycle. We report on the evolution of the giant cloud system covering its north pole using observations acquired by the Visual and Infrared Mapping Spectrometer onboard the Cassini spacecraft. A radiative transfer model in spherical geometry shows that the clouds are found at an altitude between 30 and 65km. We also show that the polar cloud system vanished progressively as Titan approached equinox in August 2009, revealing at optical wavelengths the underlying sea known as Kraken Mare. This decrease of activity suggests that the north-polar downwelling has begun to shut off. Such a scenario is compared with the Titan global circulation model of , which predicts a decrease of cloud coverage in northern latitudes at the same period of time. [Copyright &y& Elsevier]

Abstract: Titan''s fluvial channels have been investigated based on data obtained by the Synthetic Aperture Radar (SAR) instrument and the Visible and Infrared Mapping Spectrometer (VIMS) onboard the Cassini spacecraft. In this paper, a database of fluvial features is created based on radar-SAR data aiming to unveil the distribution and the morphologic and spectral characteristics of valleys on Titan on a global scale. It will also study the spatial relations between fluvial valleys and Titan''s geologic units and spectral surface units which have become accessible thanks to Cassini-VIMS data. Several distinct morphologic types of fluvial valleys can be discerned by SAR-images. Dendritic valley networks appear to have much in common with terrestrial dendritic systems owing to a hierarchical and tree-shaped arrangement of the tributaries which is indicative of an origin from precipitation. Dry valleys constitute another class of valleys resembling terrestrial wadis, an indication of episodic and strong flow events. Other valley types, such as putative canyons, cannot be correlated with rainfall based on their morphology alone, since it cannot be ruled out that they may have originated from volcanic/tectonic action or groundwater sapping. Highly developed and complex fluvial networks with channel lengths of up to 1200km and widths of up to 10km are concentrated only at a few locations whereas single valleys are scattered over all latitudes. Fluvial valleys are frequently found in mountainous areas. Some terrains, such as equatorial dune fields and undifferentiated plains at mid-latitudes, are almost entirely free of valleys. Spectrally, fluvial terrains are often characterized by a high reflectance in each of Titan''s atmospheric windows, as most of them are located on Titan''s bright ‘continents’. Nevertheless, valleys are spatially associated with a surface unit appearing blue due to its higher reflection at in a VIMS false color RGB composite with R: , G: , and B: ; the channels either dissect pure bluish surface units or they are carved into terrain with a mixed spectral signature between bright and bluish surface materials. The global picture of fluvial flows clearly indicates a high diversity of parameters controlling fluvial erosion, such as climatic processes, as well as surface and bedrock types. Recent fluvial activity is very likely in the north polar region in contrast to more arid conditions at lower latitudes and at the south pole of Titan. This divergence is probably an indication of seasonal climatic asymmetries between the hemispheres. However, traces of previous fluvial activity are scattered over all latitudes of Titan, which is indicative of previous climatic conditions with at least episodic rainfall. [Copyright &y& Elsevier]

Abstract: This is a data paper designed to facilitate the use of and comparisons to Cassini/visual and infrared mapping spectrometer (VIMS) spectral mapping data of Saturn''s moon Titan. We present thumbnail orthographic projections of flyby mosaics from each Titan encounter during the Cassini prime mission, 2004 July 1 through 2008 June 30. For each flyby we also describe the encounter geometry, and we discuss the studies that have previously been published using the VIMS dataset. The resulting compliation of metadata provides a complementary big-picture overview of the VIMS data in the public archive, and should be a useful reference for future Titan studies. [Copyright &y& Elsevier]

The overall goal of the Chesapeake Bay National Estuarine Research Reserve in Virginia (CBNERRVA) research and monitoring program is to promote, coordinate and conduct research and monitoring to enhance the scientific understanding and management of the York River and southern Chesapeake Bay coastal ecosystems. The regions of greatest scientific emphasis are located within four Reserve sites located along the York-Pamunkey River estuarine system. Primary research and environmental monitoring areas include: estuarine and shallow water environments including benthic communities, submerged aquatic vegetation and emergent wetlands habitats, open water regions and adjacent watersheds and air sheds. Both national priority (NOAA) and Chesapeake Bay specific (Chesapeake Bay Program) research focus areas are pursued within the Research Reserve with goals to: enhance scientific understanding of coastal ecosystems, surrounding environments and the natural and human processes influencing such systems; and, promote the effective management and conservation of natural and cultural coastal resources through informed decision-making. A System-wide Monitoring Program (SWMP) initiated by the Estuarine Reserves Division (ERD) of NOAA provides standardized data on national estuarine environmental trends through similar measurements of abiotic and biotic variables as well as watershed and land use classifications and measurements at each of the 27 Reserves. Data are compiled electronically at a central data management location and are available via web interface (www.vecos.org). Ongoing York River monitoring programs at the CBNERRVA reserve sites include; meteorological and streamflow monitoring, water quality monitoring and biological monitoring are available through the Reserve or via web interface. Multi-parameter water quality, in situ monitors at both fixed and buoyed stations, point sampling and continuous underway flow-through monitoring form the basis of the water quality monitoring program. Research opportunities at Reserve sites are available to any qualified scientist, academician or student affiliated with a university, college or school, non-profit organizations, and non-academic research institutions. In addition, the Reserve sponsors competitive graduate research fellowships through the NERRS Graduate Research Fellowship (GRF) Program for student research in the York River system. [ABSTRACT FROM AUTHOR]

Abstract: Titan''s vast equatorial fields of RADAR-dark longitudinal dunes seen in Cassini RADAR synthetic aperture images correlate with one of two dark surface units discriminated as “brown” and “blue” in Visible and Infrared Mapping Spectrometer (VIMS) color composites of short-wavelength infrared spectral cubes (RGB as 2.0, 1.6, 1.3μm). In such composites bluer materials exhibit higher reflectance at 1.3μm and lower at 1.6 and 2.0μm. The dark brown unit is highly correlated with the RADAR-dark dunes. The dark brown unit shows less evidence of water ice suggesting that the saltating grains of the dunes are largely composed of hydrocarbons and/or nitriles. In general, the bright units also show less evidence of absorption due to water ice and are inferred to consist of deposits of bright fine precipitating tholin aerosol dust. Some set of chemical/mechanical processes may be converting the bright fine-grained aerosol deposits into the dark saltating hydrocarbon and/or nitrile grains. Alternatively the dark dune materials may be derived from a different type of air aerosol photochemical product than are the bright materials. In our model, both the bright aerosol and dark hydrocarbon dune deposits mantle the VIMS dark blue water ice-rich substrate. We postulate that the bright mantles are effectively invisible (transparent) in RADAR synthetic aperture radar (SAR) images leading to lack of correlation in the RADAR images with optically bright mantling units. RADAR images mostly show only dark dunes and the water ice substrate that varies in roughness, fracturing, and porosity. If the rate of deposition of bright aerosol is 0.001–0.01μm/yr, the surface would be coated (to optical instruments) in hundreds-to-thousands of years unless cleansing processes are active. The dark dunes must be mobile on this very short timescale to prevent the accumulation of bright coatings. Huygens landed in a region of the VIMS bright and dark blue materials and about 30km south of the nearest occurrence of dunes visible in the RADAR SAR images. Fluvial/pluvial processes, every few centuries or millennia, must be cleansing the dark floors of the incised channels and scouring the dark plains at the Huygens landing site both imaged by Descent Imager/Spectral Radiometer (DISR). [Copyright &y& Elsevier]

Abstract: We present a quantitative analysis of CO thermal emissions discovered on the nightside of Titan by Baines et al. [2005. The atmospheres of Saturn and Titan in the near-infrared: First results of Cassini/VIMS. Earth, Moon, and Planets, 96, 119–147]. in Cassini/VIMS spectral imagery. We identify these emission features as the P and R branches of the 1-0 vibrational band of carbon monoxide (CO) near 4.65μm. For CH3D, the prominent Q branch of the ν2 fundamental band of CH3D near 4.55μm is apparent. CO2 emissions from the strong v 3 vibrational band are virtually absent, indicating a CO2 abundance several orders of magnitude less than CO, in agreement with previous investigations. Analysis of CO emission spectra obtained over a variety of altitudes on Titan''s nightside limb indicates that the stratospheric abundance of CO is 32±15ppm, and together with other recent determinations, suggests a vertical distribution of CO nearly constant at this value from the surface throughout the troposphere to at least the stratopause near 300km altitude. The corresponding total atmospheric content of CO in Titan is ∼2.9±1.5×1014 kg. Given the long lifetime of CO in the oxygen-poor Titan atmosphere (∼0.5–1.0Gyr), we find a mean CO atmospheric production rate of 6±3×105 kgyr−1. Given the lack of primordial heavy noble gases observed by Huygens [Niemann et al., 2005. The abundances of constituents of Titan''s atmosphere from the GCMS on the Huygens probe. Nature, 438, 779–784], the primary source of atmospheric CO is likely surface emissions. The implied CO/CH4 mixing ratio of near-surface material is 1.8±0.9×10−4, based on an average methane surface emission rate over the past 0.5Gyr of 1.3×10−13 gmcm−2 s−1 as required to balance hydrocarbon haze production via methane photolysis [Wilson and Atreya, 2004. Current state of modeling the photochemistry of Titan''s mutually dependent atmosphere and ionosphere. J. Geophys. Res. 109, E06002 Doi:10.1029/2003JE002181]. This low CO/CH4 ratio is much lower than expected for the sub-nebular formation region of Titan and supports the hypothesis [e.g., Atreya et al., 2005. Methane on Titan: photochemical-meteorological-hydrogeochemical cycle. Bull. Am. Astron. Soc. 37, 735] that the conversion of primordial CO and other carbon-bearing materials into CH4-enriched clathrate-hydrates occurs within the deep interior of Titan via the release of hydrogen through the serpentinization process followed by Fischer–Tropsch catalysis. The time-averaged predicted emission rate of methane-rich surface materials is ∼0.02km3 yr−1, a value significantly lower than the rate of silicate lava production for the Earth and Venus, but nonetheless indicative of significant active geological processes reshaping the surface of Titan. [Copyright &y& Elsevier]

Abstract: Titan is one of the primary scientific objectives of the NASA–ESA–ASI Cassini–Huygens mission. Scattering by haze particles in Titan''s atmosphere and numerous methane absorptions dramatically veil Titan''s surface in the visible range, though it can be studied more easily in some narrow infrared windows. The Visual and Infrared Mapping Spectrometer (VIMS) instrument onboard the Cassini spacecraft successfully imaged its surface in the atmospheric windows, taking hyperspectral images in the range 0.4–5.2μm. On 26 October (TA flyby) and 13 December 2004 (TB flyby), the Cassini–Huygens mission flew over Titan at an altitude lower than 1200km at closest approach. We report here on the analysis of VIMS images of the Huygens landing site acquired at TA and TB, with a spatial resolution ranging from 16 to14.4km/pixel. The pure atmospheric backscattering component is corrected by using both an empirical method and a first-order theoretical model. Both approaches provide consistent results. After the removal of scattering, ratio images reveal subtle surface heterogeneities. A particularly contrasted structure appears in ratio images involving the 1.59 and 2.03μm images north of the Huygens landing site. Although pure water ice cannot be the only component exposed at Titan''s surface, this area is consistent with a local enrichment in exposed water ice and seems to be consistent with DISR/Huygens images and spectra interpretations. The images show also a morphological structure that can be interpreted as a 150km diameter impact crater with a central peak. [Copyright &y& Elsevier]

Abstract: The Visual Infrared Mapping Spectrometer (VIMS) onboard the CASSINI spacecraft obtained new spectral data of the icy satellites of Saturn after its arrival at Saturn in June 2004. VIMS operates in a spectral range from 0.35 to 5.2μm, generating image cubes in which each pixel represents a spectrum consisting of 352 contiguous wavebands. As an imaging spectrometer VIMS combines the characteristics of both a spectrometer and an imaging instrument. This makes it possible to analyze the spectrum of each pixel separately and to map the spectral characteristics spatially, which is important to study the relationships between spectral information and geological and geomorphologic surface features. The spatial analysis of the spectral data requires the determination of the exact geographic position of each pixel on the specific surface and that all 352 spectral elements of each pixel show the same region of the target. We developed a method to reproject each pixel geometrically and to convert the spectral data into map projected image cubes. This method can also be applied to mosaic different VIMS observations. Based on these mosaics, maps of the spectral properties for each Saturnian satellite can be derived and attributed to geographic positions as well as to geological and geomorphologic surface features. These map-projected mosaics are the basis for all further investigations. [Copyright &y& Elsevier]