mmcirvin: (Default)
mmcirvin ([personal profile] mmcirvin) wrote2005-01-18 11:21 pm

Here's looking at you


Half-lit Mimas, centered on large crater Herschel with central peak visible

This shot of Mimas from a couple of days ago is a red-green-blue visible-light composite, though I can't vouch for the correctness of the color balance.

Mimas and Enceladus are not so different in size or distance from Saturn. Yet they are obviously nothing like each other.

[identity profile] pootrootbeer.livejournal.com 2005-01-18 10:14 pm (UTC)(link)
UH OH, THE DEATH STAR IS ALMOST COMPLETED

[identity profile] partiallyclips.livejournal.com 2005-01-19 05:19 am (UTC)(link)
Our cruishersh can't repel firepower of that magnikhude!

It's called Herschel, right?

[identity profile] sunburn.livejournal.com 2005-01-18 11:08 pm (UTC)(link)
Is Herschel always in the terminator, or is it just that those are the only interesting photos? I mean, I know that lunar craters look fantastic in the long shadows of the terminator, but, you know, Herschel's huge! Let's get some light in that thing!

Re: It's called Herschel, right?

[identity profile] mmcirvin.livejournal.com 2005-01-19 05:28 am (UTC)(link)
It's not always on the terminator, since it isn't at the pole and Mimas has Saturn-synchronous rotation. But the good photos we have up to now are all from the one fairly-close Voyager flyby, which happened over a short period of time.

I think somebody on the Celestia site pointed to one somewhere in that raw image batch in which Herschel was not on the terminator—and which revealed it to be significantly polygonal-looking, like many of the craters on Saturn's icy moons. It wasn't at this high a resolution, though.

Re: It's called Herschel, right?

[identity profile] mmcirvin.livejournal.com 2005-01-19 05:33 am (UTC)(link)
The other interesting thing to notice about Mimas is that it's visibly tidally deformed. If you turn your head sideways, it's particularly noticeable that the whole moon is stretched in the direction of the Mimas-Saturn line.
ext_8707: Taken in front of Carnegie Hall (picassohead)

[identity profile] ronebofh.livejournal.com 2005-01-19 11:04 am (UTC)(link)
Hmm, i guess tidal deformation wouldn't account for Iapetus's ridge, would it?

[identity profile] mmcirvin.livejournal.com 2005-01-19 07:07 pm (UTC)(link)
Not in and of itself, though it could conceivably have been a source of energy for tectonic processes of some sort.

Also, Mimas is really close to Saturn; Iapetus is comparatively far away, and tidal forces drop off like the inverse cube of distance.

Re: It's called Herschel, right?

[identity profile] mmcirvin.livejournal.com 2005-01-19 05:41 am (UTC)(link)
Herschel not on the terminator (http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=29828) (and a freaking enormous canyon).

The non-Herschel side. (http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=29902)

The tidal stretching is particularly noticeable here. (http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=29962)

Also this shot is pretty cool (http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=30175), very Chesley Bonestell.