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The Cassini Visual and Infrared Mapping Spectrometer (VIMS) is an imaging spectrometer coveting the wavelength range 0.3-5.2 [micro]m in 352 spectral channels, with a nominal instantaneous field of view of 0.5 mrad. The Cassini flyby of Jupiter represented a unique opportunity to accomplish two important goals: scientific observations of the jovian system and functional tests of the VIMS instrument under conditions similar to those expected to obtain during Cassini's 4-year tour of the saturnian system. Results acquired over a complete range of visual to near-infrared wavelengths from 0.3 to 5.2 [micro]m are presented. First detections include methane fluorescence on Jupiter, a surprisingly high opposition surge on Europa, the first visual-near-IR spectra of Himalia and Jupiter's optically-thin ring system, and the first near-infrared observations of the rings over an extensive range of phase angles (0-120[degrees]). Similarities in the center-to-limb profiles of [H.sup.+.sub.3] and C[H.sub.4] emissions indicate that the [H.sup.+.sub.3] ionospheric density is solar-controlled outside of the auroral regions. The existence of jovian N[H.sub.3] absorption at 0.93 [micro]m is confirmed. Himalia has a slightly reddish spectrum, an apparent absorption near 3 [micro]m, and a geometric albedo of 0.06 [+ or -] 0.01 at 2.2 [micro]m (assuming an 85-km radius). If the 3-[micro]m feature in Himalia's spectrum is eventually confirmed, it would be suggestive of the presence of water in some form, either free, bound, or incorporated in layer-lattice silicates. Finally, a mean ring-particle radius of 10 [micro]m is found to be consistent with Mie-scattering models fit to VIMS near-infrared observations acquired over 0-120[degrees] phase angle. Keywords: Jupiter; Jovian satellites; Jupiter's ring; Spectroscopy; Planetary atmospheres; Planetary surfaces; Cassini mission

Abstract: Infrared-optical tracking systems are essential for virtual reality and augmented reality environments; moreover, also video games and entertainment applications can take advantage of real 6-DOF trackers. Unfortunately, specialized hardware is often used, and this leads to a lack of affordability, thus delaying or averting the adoption of this technology. This paper presents an extremely affordable tracking system based on Wii remotes used as IR cameras. The proposed solution allows to track in real-time a 6-DOF target at a cost of less than one thousand dollars. Moreover, the tracking system has been integrated within an open source 3D content creation suite to deliver a flexible and extensible graphics tool. [ABSTRACT FROM AUTHOR]

Abstract: We present the Messinian evaporite suite (Mediterranean region) and the Solfatara hydrothermal system (Phlegraean Fields volcanic province, Italy), discuss their implications for understanding the origin of sulfates on Mars and show preliminary sets of VNIR laboratory and in situ reflectance spectra of rocks from these geologic systems. The choice was based on a number of evidence relative to Mars: (1) the chemistry of the Martian sulfates, suggesting fluid interactions with possibly alkali-basaltic rocks and/or regolith; (2) close range evidence of sulfates within sedimentary formations on Mars; (3) sulfate spectral signatures associated to large-scale layered patterns interpreted as thick depositional systems on Mars. The Messinian evaporites comprise three units: primary shallow-water sulfates (primary lower gypsum: PLG), shallow- to deep-water mixed sulfates and clastic terrigenous deposits (resedimented lower gypsum: RLG), and shallow-water associations of primary sulfates and clastic fluvio-deltaic deposits (upper evaporites: UE). The onset of the Messinian evaporites records the transition to negative hydrologic budget conditions associated with the Messinian Salinity Crisis, which affected the entire Mediterranean basin and lasted about 640kyr. The Solfatara is a still evolving hydrothermal system that provides epithermal deposits precipitated from the interaction of fluids and trachybasaltic to phonolitic rocks. Thermal waters include alkali-chloride, alkali-carbonate and alkali-sulfate endmembers. The wide spectrum of sedimentary gypsum facies within the Messinian formation includes some of the depositional environments hitherto identified on Mars and others not found on Mars. The PLG unit includes facies associations correlated over long distances, that could be a possible analog of the stratified rock units exposed from Arabia Terra at least as far as Valles Marineris. The facies cycles within the UE unit can be compared to the sequences of strata observed in craters such as Holden and Eberswalden. The UE unit records paleoenvironmental changes which are ultimately controlled by terrestrial climatic variations. They can be considered as a reliable climatic proxy and may be useful for the reconstruction of climatic events on Mars. The intermediate Messinian RLG unit has not, at present, a well-defined depositional counterpart on Mars, although there are some similarities with the northern lowlands and Vastitas Borealis Formation. The dramatic variation of hydrologic budget conditions at the onset of the Messinian evaporites may provide criteria for the interpretation of similar variations on Mars. The volcanic rocks at the Solfatara bear some similarities with the “alkaline magmatic province” observed at the Gusev crater on Mars, and the assemblages of hydrothermal phases resulting from the Solfatara''s parent rocks could be analogues for processes involving Gusev-type rocks. The Messinian sulfates have a prevalent Ca-sulfatic composition and wide textural variability. Preliminary laboratory reflectance spectra of rock samples in the VNIR region reveal the signature of sulfates and mixtures of several Fe-bearing phases. At the Solfatara, in situ reflectance measurements of epithermal minerals close to active fumaroles showed the presence of Fe-bearing sulfates, hematite, Al- and K-sulfates and abundant amorphous fraction. XRD analysis supported this interpretation. The range of depositional facies observed in the Messinian units and the variety of minerals detected in the Solfatara will be useful for the interpretation of close range data of Mars. The spectral characterization at various scales of the Messinian sedimentary facies and the Solfatara hydrothermal minerals will both help in the exploration of Mars from orbit and with close range inspection. [Copyright &y& Elsevier]