S. Fussner's research while affiliated with The University of Arizona and other places

... The mere existence of aeolian features carries the implication that winds can be forceful enough to move surface materials. But the type and orientation of dunes (and aeolian features in general, notably streaks; e.g., Turtle et al., 2007) can be used to infer the net transport direction of material-in essence a weighted vector sum of the long-term wind field. The weighting may be roughly by the cube of wind speed, since transport is highly non-linear (opinions vary as to whether a threshold-andsquare law or a cube-law is most appropriate; e.g., Townsend, 1976;McLean et al., 1994). ...

... Earth's overall, opaque haze layers block most visible light from the Sun and other sources and obscures Titan's surface features[26]. Titan's lower gravity means that its atmosphere is far more extended than Earth's[27]. The atmosphere of Titan is opaque at many wavelengths and as a result, a complete reflectance spectrum of the surface is impossible to acquire from orbit. ...

... All rights reserved.Earth and Mars). Titan's polar vortex[Teanby et al., 2008;de Kok et al., 2014;West et al., 2015] could represent an interesting case for future studies since the polar clouds show the emergence of a seasonal cloud similar in shape to Venus SPV. Additionally, Titan's intermediate rotation rate between Venus and Earth-Mars and the presence of strong seasonal effects like Earth and Mars add intriguing properties to the polar vortices puzzle.So far, there have been few attempts to model the structure and dynamics of Venus' polar vortices. ...

... The Cassini spacecraft, which has been observing the Saturnian system since 2004 and is now in its extended mission named Solstice, and its probe Huygens have shown the existence of a methane cycle on Titan similar to the hydrological cycle on Earth. Cassini first detected liquid bodies in the southern polar region of Titan surface in 2004 by means of the imaging science subsystem 1 (ISS) (McEwen et al. 2005). Its Radar 2 showed dark patches, interpreted as lakes, in the northern polar region in 2006 (Stofan et al. 2007). ...

... The Cassini mission had a radar imager to survey the surface of Titan through its thick atmosphere. The radar imager operating at 13.7 GHz made the first detailed surface map of Titan with a pixel resolution of 0.3 km (Porco et al. 2005). Radar imaging, or "radiometry", on-board Cassini, has also allowed determination of the temperature of any object. ...

... The reason of the upper limit for the phase angle is to ensure that most of the dayside is seen, and to limit the dependence on the observing conditions, while an upper limit on the solar incidence angle is set in order to ensure that the selected pixels are seen with a fair solar illumination (far enough from the terminator, in order to have a good SNR) and in a limited range of local times. On the other hand, the upper limit on the emission angle lies in the fact that, in Titan images, contrast decreases with increasing emission angle, with a decrease that seems to be approximately linear with emission angle (Fussner et al., 2005). From 0° to 60° emission angle, the optical depth of haze changes by a factor of two, meaning that light leaving the planet from 60° emission angle must pass through twice as much haze as light leaving at 0°. ...