[X] My Assistant

[ugordan]

Are there any plans for imaging Rhea on March 21? I noticed all other moons are on the wrong side of Saturn during periapsis passage except Rhea for which there's a pretty close pass, under 100 000 km, although closest approach happens at a very high phase angle.

Rhea approach geometry and closest approach from the Solar System Simulator.

[edstrick]

AMEN. I don't understand why so much geometry change between frames.. this is not a super close encounter. (sigh)

[ugordan]

AMEN. I don't understand why so much geometry change between frames.. this is not a super close encounter. (sigh)

When you have typically a minute between frames, even a slow encounter is bound to produce a difference. Take a multispectral observation of each footprint and the whole thing just falls apart.

Ciclops is quite old remember, it probably had to have its design frozen about 12 years ago.

I don't buy it. Galileo's SSI is basically early '80s or even late '70s technology and apparently it was much faster in terms of snapping images.
The problem might be due to the design of the SSR recorders on Cassini and their peak throughput, combined with other instruments' simultaneous demands. In light of that, the ISS team probably relaxed the speed in which the images could be taken.

[ugordan]

There's a high phase Enceladus sequence on the raw site now.
I stacked 6 frames and greatly enhanced the result to show the plumes emanating from the south pole:


The right image uses a color map to better show the extent of the plumes. The short sliver on the bottom left side of Enceladus' disk is the actual sunlit side, while the rest is saturnshine-lit region, severely saturated. The white region on the bottom are the rings, also heavily overexposed and motion-blurred.
JPEG artifacting is obvious even after stacking but the plumes are clearly still there.