All,
Those 'straight-line' objects on Dione and Rhea. Ages ago, I posted about them on the Asterisk to get others' views and didn't. Just today, craterchain has suggested that such objects are the result of the impact of tidally fragmented objects. Googling for "crater chains" gets several clear examples, on the Moon, Callisto and even possibly the Earth, though some refer to "extraterrestrial strafing runs". I suppose that explanation IS about right, if you take out the "intelligence"!

Still, it worries me that the features that originally caught our attention, Travis' Fissure etc., are remarkabaly smooth sided for crater chains, or is that the result of 'image manipulation'?

John