|
|
 |
Imaging Diary - Cassini
Imaging Diary - Voyager
Newsroom - Press Releases
Newsroom - Special Events
| |
| Mimas...Closer Than Ever Before - Aug 5, 2005 | | | Cassini's closest flyby of Mimas on August 2nd revealed it to be one of the most heavily cratered Saturnian moons, with variations in color across its surface but little if any evidence for internal activity. |
|
Home - Captain's Logs
| |
| A Story of Saturn's Rings - Nov 1, 2010 | | | ... orbital gravitational resonance with Mimas known to be responsible for its ... to become trapped in the strong Mimas resonance at the B ring's edge ... |
|
Maps
Artroom
Newsroom - Looking Ahead
Alliance Member Comments
Mimas Showing False Colors |
Moonsister 2007-04-20 23:14:11 | View all member's comments | Somewere I saw a caption for a similar pic of Mimas called "Saturn's tortured moon Mimas". What a hit! It is surpriing Mimas didn't explode from the impact and become another ring. | |
Death Star at Saturn |
Red_dragon 2007-01-19 02:20:18 | View all member's comments | With three Death Star-like moons in orbit around Saturn (Mimas,Tethys,and Iapetus),be careful or you'll receive the visit of a guy dressed with black ropes,asmatic problems,and a sword of light :) | |
Mimas and Calypso Rev 126 Flyby Raw Preview |
NeKto 2010-02-18 10:16:17 | View all member's comments | Carolyn, i greatly appreciate the fact that the team leader at CICLOPS can look at these images, see the gist of all the scientific information they offer, and still see the resemblance to the head of a fish. perhaps that is one of the reasons why so many of the images you (the whole team) have shared with us are so artistic, awe inspiring, and breathtaking.
one thing that strikes me about Mimas is what i have been calling "slump craters" a formation typical on one of the outer irregular moons whos name excapes me at the monent. i am refering to craters that sugjest low density crust with a goodly amount of space between ice crystals. making craters that look like the impactors compress more than excavate. | |
Mimas and Calypso Rev 126 Flyby Raw Preview |
ultomatt 2010-02-15 16:45:41 | View all member's comments | Love the images of Mimas, especially the high res imagery of the inside of Herschel crater. Quite a chaotic landscape! I've checked through the raw imagery and there appears to be a borderline between the crater wall and the slump features...almost like a black outline...very curious. There appears to be a layer of dark material at the transition between the avalanche features and the steep crater wall. I've been waiting a long time to see details inside this amazing crater...you haven't disappointed, once again!
And then there's Calypso at what, 30 kilometers in the long axis? What an amazing image of that tiny bit o' real estate! The flow features on the surface bear a resemblance to glacial features on Earth, with a serpentine path evident. There appears to be a river of ice flowing from top right to center bottom in the image. And the near total absence of craters makes it clear that this is a very young surface that has likely been the result of the accumulation of ices on the surface, from the E-ring. I haven't been able to find a reference to Calypso's gravity, but it certainly is minuscule, and the flow features would move in interesting paths with so little friction and weight. Seems like ices could almost literally float in gravity so low. Wouldn't take a lot of energy to move the particles "downhill". | |
Prometheus and Dione Rev 125 Flyby Raw Preview |
ultomatt 2010-01-29 12:01:00 | View all member's comments | The image of Prometheus is stunning! The lighting looks especially strange...is this the result of ring shadow? I hope that Cassini lasts long enough to really focus on the small moons. Titan is an amazing moon, but each of the moons has a profound story to tell, and after dozens of Titan encounters, how bout shifting the focus onto the lesser moons? For instance, the crater Herschel on Mimas has yet to be imaged at high resolution. The high res sequence of Mimas was of the opposite hemisphere.
I know it's a matter of fuel and trajectory, and the orbits have pretty much designed to optimize viewing at Titan, but isn't it time to shift the focus to some of the other moons? With limited resources, and the inevitable end of the mission looming, I find it kind of frustrating seeing these amazing shots of the lesser moons, and realizing that these are secondary and tertiary objects relative to the mission's primary goal, which was to draw back the curtains on Titan. That's been achieved...more of the little moons, PLEASE!
And, don't get me wrong...this is one of THE greatest space missions in the history of spaceflight. Kudos for many jobs well done! | |
Special Holiday Raw Preview! |
Dragon_of_Luck_Mah_Jonng1971 2009-12-31 15:54:56 | View all member's comments | Thank you ultomatt for writing about the Feb. 17 Mimas flyby. For me, it's interesting to get images of Herschel crater at higher resolution,too. In the actual list of the 2010 tour dates they rescheduled it to the 13th of Feb. , 2010. Shortly after the last one of the 2 very interesting 2009 Enc Nov. flybys there was a flyby of Rhea not listed as a "close" one, but nevertheless having enabled new looks of Rhea. ( with tectonic features similar to Dione ) This perhaps means that at Mimas this will be possible without a close flyby. That Rhea flyby was at 24000km, 15000 mls.
Thank you for writing here of those flybys: Rhea Mar. 2nd and Dione April 6th.
At the Equinox Mission there aren't planned any close flybys of Tethys. But I think that imaging of the remarkably large Odysseus basin ( not only being a 'crater' ) at many better resolution than the best images of it by the Cassini spacecraft available at this moment would be very interesting.
After looking at the actual list of the 2010 tour dates I found those flybys among other ones: On Jan. 10 at Methone at 27000 km, 17000 mls, On Feb. 13 at Mimas at 10000 km, 6000 mls ( as mentioned ) and on June 3 at Tethys, 53000 km, 33000 mls. Perhaps that Tethys flyby will include almost Cassini-class Hi-Res images of the Odysseus basin. | |
Special Holiday Raw Preview! |
ultomatt 2009-12-29 00:57:54 | View all member's comments | Great imagery. Titan is, of course, the jewel of the system, but every single moon has a unique story to tell. I am looking forward to the close flyby's coming up in 2010 of some "lesser" moons, like Mimas on Feb. 17 (not listed as a "close" flyby, but I mention it cause I hope that higher res imagery of Herschel will be possible) Rhea on March 2nd, Helene on March 3rd, Dione April 6th, Enceladus on April 27th & May 18th. The small moons have a lot to reveal at a much finer scale than the global attention at Titan. Don't get me wrong, the focus on Titan was clearly the proper thing to do, but personally I'm a little sad that more flybys of Iapetus weren't possible, but I understand that it is further out and more fuel intensive to get to. My point is, as in the Japanese success at Itokawa, it is clear that small celestial objects have unique data to provide to the ever expanding puzzle that is the solar system. | |
More Ring Arcs for Saturn |
carolyn 2008-09-20 03:44:16 | View all member's comments | Red_dragon: The origins of all ring arcs are similar in that to get longitudinal confinement to make an arc requires a particular type of resonance. In the case of Methone and Anthe, it is resonances from Mimas that confine the two moons. The particles in the arcs, which almost certainly come from the moons, are therefore also confined by Mimas. In the case of Neptune's arcs, resonances from Galatea confine them longitudinally and radially. We never saw moons like Methone and Anthe within the Neptune arcs, but then Voyager didn't have the capability to see such tiny moons directly. | |
Targeting the Jet Sources |
TomMadigan 2008-08-20 02:28:43 | View all member's comments | Pipipot and NeKto:
When trying to answer questions such as these, it occurs to me that we should first look for similarities between Saturn and any interactions with its satellites and similar interactions between its larger sibling, Jupiter and its entourage of satellites. It’s well documented that the lion’s share of the energy that fuels Io’s active volcanoes is derived from tidal heating. Because of its proximity to Jupiter and its orbital eccentricity, Io endures continued tidal flexing from Jupiter’s exceedingly strong gravity. Explained differently, the force that Jupiter’s gravity exerts on Io changes significantly from one point to another (a differential change) along a line connecting the two centers of mass. This differential force is the same “tidal force” that gives us the tides here on earth and is responsible for the harmonious gravitational interplay between the earth and the moon. This tidal flexing induces internal frictional heating and is the primary cause for Io’s active volcanism.
When you consider that Enceladus has an orbital eccentricity almost identical to Io’s and, like Io, is in close proximity to its host planet (Io is the closest of the major Jovian satellites; Enceladus is the second only to Mimas), its no accident that we see evidence of internal heating, heating no doubt caused by tidal flexing. It is quite possible that the Cryovolcanism we observe on Enceladus is caused by very similar processes as that which produces Io’s volcanism. Although the tidal force endured by Enceladus is more than ten thousand times less than that endured by Io, it should be noted that Saturn has only 10% the mass of Jupiter with a density less than that of water. Another factor that figures in significantly here is that Enceladus is at an orbital distance from Saturn that is only 4 times the Roche distance (for Enceladus and Saturn). Any two bodies where the lesser of the two goes inside the Roche limit, that body will be disrupted as the tidal force exceeds the self-gravitation of the body, resulting in its destruction or material disassociation. The closer to the Roche distance, the greater any tidal effects will be.
| |
|
