[X] My Assistant

[dilo]

Pretty images on Jul,17 showing Rhea and, on the far right, Mimas with Saturn on background:

In the wide-angle picture I decided to register images on Rhea subject and I tried to match colors of narrow-angle, so sorry for weird Saturn border... sharpening after jpeg-artifacts removal done too.

This is the simulated view:


I wasn't able to identifiy this small object visible only in the green image, inside rings:

It seems real, could be Pan?

[Ian R]

Here's a stacked, IR-Green-UV composite, at a very low phase angle:



Is it my imagination, or is that bright spot at the center of the disc a result of the zero-phase 'opposition effect' ?



Ian.

[ugordan]

Is it my imagination, or is that bright spot at the center of the disc a result of the zero-phase 'opposition effect' ?

It doesn't fit to where one would expect a zero phase peak, it more looks like the subsolar point (i.e. the point where shadows and topographic relief disappear) that brought out an otherwise brighter patch at that location. The phase angle at the time was around 16 degrees and Rhea subtended only 6 arcmin in diameter so it couldn't have been the opposition surge even theoretically.