Looks like a space-ship to me...
Cassini flew closer to Tethys than originally planned, and captured this image of the surface. Note the strange arrow feature.
Now, note that it is raised above the surrounding landscape. It is symetrical. It has a large protruding, forward swept 'fin' on its top side. Presumably there is one on its underside aswell. You can see that the top fin casts a shadow on the landscape - it appears to be perfectly vertical.
When this ship did a controlled crash landing on Tethys, its lower fin dug into the regolith of the planet, slowing it down, and causing the streak behind it.
The first image of an ancient alien spacecraft? It seriously could be.
Just what I think. This image was just released.
Boy would that make an obscure modelling subject...
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