[X] My Assistant

[ugordan]

To wrap up the year, Cassini took a few Tethys low phase images from about 400 000 km.
A stretched color (IR/G/UV) composite:

[edstrick]

TedStryk's voyager picture shows the most puzzling nature of the stripe quite well... it's a relatively uniform dark band with rather sharp edges, like it was painted on with a giant paintbrush in a single swipe. It just doesn't make much sense.

[ugordan]

Here's another one showing the band. It's not very precisely defined, more looks like it was sprayed, not painted on. The image also shows the boundary between two types of terrain -- the lower third of the disc is visibly less cratered than the rest of the moon.

[Bob Shaw]

I see lots of linear terrain morphologies on Tethys!



Here's my take on it: it's a sub-scale Iapetus ridge effect, the same mechanism writ small (or large).

Impacts take place; debris is ejected. Some goes into orbit of Saturn. Said debris is perturbed into arcs, and a proportion impact the parent body - in arcs. Note that the bands all have reasonably low inclinations, too.


Bob Shaw