Using Shadows To Measure the Geysers of Enceladus

The Bad Astronomer writes "A lot of folks are posting about the amazing new pictures of the icy moon Enceladus returned from the Cassini spacecraft. However, one of them shows the shadow of the moon across the geyser plumes. This has been seen before, but I suddenly realized how that can help determine the geysers' locations, and I thought Slashdot readers might be interested in the general method."

Two serious questions:

[Anonymous Coward]

1) What sort of freaky small time window and lighting conditions do they need to get a picture at a range of 185 km [ciclops.org], and can they do it consistently? That's insanely close for how fast this spacecraft is traveling across the surface of the moon, and for the lighting conditions.

2) Unrelated, but what the hell are those things at lower left (and two of them crossing in upper-mid-to-upper-right)this pic [ciclops.org] from a more more sane 17000 km? Ridiculously long crater chains from ejecta, or something rolling/bouncing "downhill"? Seems weird that it could roll "downhill" through a crater without altering its path, so I'm leaning towards crater chains from ejecta, but they seem pretty wildly extended for crater chains, yet are too varied in direction to suggest faults. Where was this relative to the "tiger stripes"?