Dioné et Thétys

[symaski62]

http://saturn.jpl.nasa.gov/multimedia/i ... geID=33210

Dion?© et Th?©tys

[eburacum45]

Je vous remercie.
and this one is interesting- you can see the Saturnshine too
http://saturn.jpl.nasa.gov/multimedia/i ... 028847.jpg

[Ynjevi]

I too thought that the moon in background was Tethys. But it is actually Rhea. On February 20th Dione passed over Rhea, and on 21th over Tethys. These images were taken on 20th February. Tethys was the on the other side of Saturn.

[tony873004]

I can only see Saturnshine on the smaller moon, the one that passes behind the other moon. But I need to brighten it in Photoshop. Then I can see it in both pictures.

That's so cool to realize that that's a real picture and not something pasted together.

[Matt McIrvin]

I too thought that the moon in background was Tethys. But it is actually Rhea. On February 20th Dione passed over Rhea, and on 21th over Tethys. These images were taken on 20th February. Tethys was the on the other side of Saturn.

It fooled me too, when this came up in the Bad Astronomy forums! The perspective makes Rhea look only as big as Dione (or Tethys), but it is actually bigger and further from Cassini. And the rugged topography near the terminator isn't Ithaca Chasma-- it's Rhea's "wispy terrain", now lit from the side.

[Matt McIrvin]

I can only see Saturnshine on the smaller moon, the one that passes behind the other moon. But I need to brighten it in Photoshop. Then I can see it in both pictures.

The reason you can only see the Saturnshine on Rhea is that Dione is in front of Saturn and Rhea is behind Saturn! Rhea is actually bigger than Dione, and you're looking right across the orbits of the icy moons.

It's a strange trick of perspective that they look to be near one another.

You might be able to see just a little Saturnshine near the limb of Dione, but don't expect much...

[Matt McIrvin]

This picture really is of Dione and Tethys. Interesting comparison of the trailing hemispheres of both... Dione's is much darker.