[X] My Assistant

[Rob Pinnegar]

Quite a few of the Cassini narrow-angle shots of Titan that have come down the wire in the past couple of days show a white smear at left of centre, which is in the same location regardless of where the camera is pointing. It's really obvious if you look at two or three of the images.

I was worried about this at first, because I had never noticed it before, and thought it was some recent piece of damage to the lens, caused by an impact with a big dust grain or something like that.

However, after looking back at some images of Titan from a couple of weeks ago (Sept. 8th), it shows up in a few places there, too. It only seems to be visible at certain lighting levels, and the recent photos just happen to showcase it.

It doesn't show up at all in the recent ring photos, so it can't be that serious. Still, it threw me for a scare, so I thought I'd ask about it, reasoning that others might be wondering the same thing.

Why does this thing look different from the "donut-shaped" dust artifacts that are visible elsewhere in the field of view; for example, the small one at 4 o'clock that can be seen in many narrow-field shots? The "splat" has a donut-shaped artifact within it. Are they related to each other?

[ljk4-1]

Perhaps it is a ring particle.

Rather than consider it a nuisance that one wishes could be wiped off,
perhaps there is a way to examine such a bonus opportunity via the
camera, since Cassini was never meant to collect ring particles.

Has there already been a discussion about sending a Stardust type
mission to Saturn to collect ring particles for return to study? Could
it also be designed to swing by Enceladus to pick up some geyser
debris, too?

[Borek]

By the way, Cassini ISS really has a electro-mechanical shutter?

Borek