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Titan's atmosphere from ISO mid-infrared spectroscopy
Lellouch, E.; Feuchtgruber, H.; Coustenis, Athena +5 more
We have analyzed Titan observations performed by the Infrared Space Observatory (ISO) in the range 7-30 µm. The spectra obtained by three of the instruments on board the mission (the short wavelength spectrometer, the photometer, and the camera) were combined to provide new and more precise thermal and compositional knowledge of Titan's stra…
Observations with the Visual and Infrared Mapping Spectrometer (VIMS) during Cassini's flyby of Jupiter
Sotin, C.; Brown, R. H.; Baines, K. H. +24 more
The Cassini Visual and Infrared Mapping Spectrometer (VIMS) is an imaging spectrometer covering the wavelength range 0.3-5.2 µm 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 jovia…
Saturn's wayward shepherds: the peregrinations of Prometheus and Pandora
French, Richard G.; Dones, Luke; Lissauer, Jack J. +1 more
Saturn's narrow F ring is flanked by two nearby small satellites, Prometheus and Pandora, discovered in Voyager images taken in 1980 and 1981 (Synnott et al., 1983, Icarus 53, 156-158). Observations with the Hubble Space Telescope (HST) during the ring plane crossings (RPX) of 1995 led to the unexpected finding that Prometheus was ∼19° behind its …
The photochemical formation of a titan haze analog. Structural analysis by x-ray photoelectron and infrared spectroscopy
Tran, Buu N.; Ferris, James P.; Chera, John J.
The photochemical flow reactor (D.W. Clarke et al., 2000, Icarus 147, 282-291) has been modified to minimize the incorporation of oxygen and other impurities in the photoproducts. A mixture of gases that approximate their mixing ratios on Titan (N 2, CH 4, H 2, C 2H 2, C 2H 4
The hydrogen ortho-to-para ratio in the stratospheres of the giant planets
Lellouch, Emmanuel; Fouchet, Thierry; Feuchtgruber, Helmut
Observations of the H 2 S(0) and S(1) quadrupole lines in the four giant planets by the short-wavelength spectrometer of the Infrared Space Observatory are analyzed. These lines probe pressure levels located between 10 and 1 mbar and allow us to determine the stratospheric hydrogen para fraction for the first time. In Jupiter and Saturn…
Neptune's far-infrared spectrum from the ISO long-wavelength and short-wavelength spectrometers
Swinyard, Bruce M.; Orton, Glenn S.; Feuchtgruber, Helmut +4 more
Neptune was observed by the Infrared Space Observatory (ISO) Long-Wavelength Spectrometer (LWS) between 46 and 185 µm. At wavelengths between 50 and 110 µm the accuracy of these measurements is ⩽0.3 K. Observations of this planet made by the ISO Short-Wavelength Spectrometer between 28 and 44 µm were combined with the LWS data to…
Photometry of pluto in the last decade and before: evidence for volatile transport?
Buratti, B. J.; Heinze, A.; Young, J. +7 more
Photometric observations of Pluto in the BVR filter system were obtained in 1999 and in 1990-1993, and observations in the 0.89-µm methane absorption band were obtained in 2000. Our 1999 observations yield lightcurve amplitudes of 0.30 ± 0.01, 0.26 ± 0.01, and 0.21 ± 0.02 and geometric albedos of 0.44 ± 0.04, 0.52 ± 0.03, and 0.58 ± 0.02 in …
The dynamics of jovian white ovals from formation to merger
Marcus, Philip S.; Youssef, Ashraf
In early 1998 two of the three, long-lived anticyclonic, jovian white ovals merged. In 2000 the two remaining white ovals merged into one. Here we examine that behavior, as well as the dynamics of three earlier epochs: the Formation Epoch (1939-1941), during which a nearly axisymmetric band broke apart to form the vortices; the Kármán Vortex Stree…
The mass ratio of Charon to Pluto from Hubble Space Telescope astrometry with the fine guidance sensors
Olkin, C. B.; Franz, O. G.; Wasserman, L. H.
The mass ratio of Charon to Pluto is a basic parameter describing the binary system and is necessary for determining the individual masses and densities of these two bodies. Previous measurements of the mass ratio have been made, but the solutions differ significantly (Null et al., 1993; Young et al., 1994; Null and Owen, 1996; Foust et al., 1997;…
EPIC simulations of the merger of Jupiter's White Ovals BE and FA: altitude-dependent behavior
Dowling, Timothy E.; Sánchez-Lavega, Agustín.; Morales-Juberías, Raúl
Observations of the merger of Jupiter's White Ovals BE and FA show altitude-dependent behavior that we seek to capture in numerical simulations. In particular, it was observed that the upper portions of the vortices orbited each other before merging, but the lower portions translated into each other without orbiting, a phenomenon we term the pair-…