Crack azimuths on Europa: the G1 lineament sequence revisited

Cycloidal cracks on Europa: Improved modeling and non-synchronous rotation implications

“…Given that the work of Sarid et al (2004Sarid et al ( , 2005 suggests that there are no convincing systematic changes in crack azimuth in the tectonic record, these cycloid studies provide compelling evidence for the non-synchronous rotation of Europa. It also supports the hypothesis that only a few ridges form in any given non-synchronous rotation cycle.…”

“…However, inspection of the area Geissler studied with higher resolution image data by Sarid et al (2005) showed that a minimum of two periods of non-synchronous rotation would be required to fit the sequence of ridges, much more rotation than the original result of Geissler et al (1998aGeissler et al ( , 1998b. Sarid et al (2005) noted that, given enough cycles of rotation, even a random sequence of azimuths could fit a model of nonsynchronous rotation. In examining that possibility, Sarid et al (2005) demonstrated that the statistics of the azimuthal sequence in that region do not provide a clear, compelling signature of non-synchronous rotation.…”

“…Sarid et al (2005) noted that, given enough cycles of rotation, even a random sequence of azimuths could fit a model of nonsynchronous rotation. In examining that possibility, Sarid et al (2005) demonstrated that the statistics of the azimuthal sequence in that region do not provide a clear, compelling signature of non-synchronous rotation. Those studies did show that, if Europa is rotating non-synchronously, relatively few ridges form in each cycle.…”

The influence of obliquity on europan cycloid formation

“…For example, tidal stresses affect the azimuthal orientation of cracks Sarid et al, 2002Sarid et al, , 2005Sarid et al, , 2006aHurford, 2005). The possible effect of obliquity on that work should be considered.…”

Crack azimuths on Europa: Sequencing of the northern leading hemisphere

“…That result required the sequence to have occurred over a minimum of several nonsynchronous rotation periods, not within a single period. Sarid et al [2005] concluded that far fewer features formed during each nonsynchronous rotation period than originally thought.…”