... of Saturn's moons Methone and Tethys on May 20, 2012.With a close-approach ... Cassini flew by the larger moon Tethys at a distance of about 34,000 ... that encounter are included here. Tethys is 660 ...
... of Saturn's moons Enceladus and Tethys were taken on April 14, 2012, ... encounter, Cassini passed the moon Tethys with a closest approach distance ... Cassini's best imaging encounter with Tethys ...
A recent tweak to Cassini's trajectory allowed an even closer approach of 1,500 kilometers (930 miles) to the Saturnian moon, Tethys, than originally planned, and yielded unrivaled views of the icy moon’s cratered landscape and a look into the gargantuan canyon system called Ithaca Chasma.
Another interesting mug shot of Helene, the leading Trojan moon of Dione. Helene is only 36 KM by 32 KM by 30 KM in size, where as Dione is 1,123 KM wide!!!! Mind you the trailling trojan moon Polydeuces is much smaller again, perhaps only 3 KM wide!!!!!!!!
What is interesting to see is that the three trojan moons seen up close to date (Helene for Dione as well as Telesto & Calypso for Tethys) is that thet all have smoother profiles & certainly Calypso & Helene display flow like features. Are they sweeping up ice crystals ejected from Enceladus's geysers???
Absolutely, fantastic image. Also because their distances from Cassini were not that much different, the small difference in size is apparent. Dione @ 1,123 KM wide & Tethys @ 1,063 KM wide. Mind you Dione has nearly twice the mass of Tethys due to it's much greater density & also Tethys appears unevolved & primitive, where as Dione has certainly seen much geological activity in the relatively 'recent' past & may still be active on a small scale.
NeKto, ijusth: I found the answer on the Cassini Mission main page.
When I searched on this page for 'E ring' I got many results, the interesting one is the 3rd one of 'News' :Home > News & Features > Cassini Science League > 'How a Celestial Snowblower Runs a Ring Around Saturn'. ( Published on March 23, 2010 )
( Type E ring followed by the enter key into the search window even if the page may indicate 'no results found' before pressing the enter key. )
The particles of Enceladus' jets are falling on Enc or making it into the E ring. Those ones in the E ring are falling back on Enc within one or two orbits or falling back on Enc after a much longer stay in the ring, but estimated not to be for more than 400 years. Some very few make it from the E ring into the magnetosphere. But material from impact cratering in the present on Enceladus is more than the particles lost to the magnetosphere I think. Thus Enceladus doesn't shrink. Enceladus is getting also material from micrometeorites.
(Even if scientists say that Tethys is brighter than Dione because it's getting material from the E ring, too, I think that the material from impacts and from micrometeorites on Enc is enough that Enceladus doesn't shrink although giving some material to Tethys. )
NeKto: This question has been answered by carolyn in 2009 already, the jets produce a thrust that is only miniscule.
I wanted to know why does Titan orangish hue is not perfectly spherical around the edge of where Tethys is behind it (in the first image)
I don't think it's from the surface of Titan, probably there is some thickness differences around that area on the north, it seems that the bluish atmosphere is thicker than the orangish atmosphere on that side???? no??
Interesting image definitely ...
A GREAT -in all senses- image. And the best things are: 1) try to find Tethys' shadow, 2) compare with earlier images to see how has been disappearing Saturn's blues. Keep up the good work! (and, by the way, hope to see soon a Voyager-like Cassini's picture of Saturn)
High quality comments, keep them coming. As a side note, it's amazing how a body so small as Enceladus is so active while Tethys which is certainly more massive is dead, or at least very nearly so. Perhaps its low density compared with the relatively high density of Enceladus has something to tell?