Dione images & information.

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Saturn moon Dione is the fifth major moon out from Saturn. Dione orbits Saturn at a distance of 562,000 KM once every 2 days, 14 hours & 43 minutes, which is the same as the rotational period. Dione is Kronesynchronous, so keeps the same face turned towards Saturn all of the time.

Dione is the third densest of Saturns moons with a mean density of 1.478 G/CM3 roughly, 46% rock / metal & 54% ice.

Dione is 1,128 KM wide, very similar to Tethys, the Uranus moons Ariel & Umbriel & the large moon of KBO 134340 Pluto, Charon.

A few images below.

Dione in front of Saturn. Voyager 1.

A gibbous Dione from Voyager 1, the first ever decent view of this moon of Saturn. Craters, smoother plains & tectonic canyons are clearly visible.

Dione in front of Saturn's limb, Tuesday 11th October 2005. It was Winter in the northern hemisphere of both Saturn & Dione when this was obtained.

Crescent Dione Cassini.

Dione southern hemisphere. Cassini.

Dione northern hemisphere with tectonic canyons Cassini.

Dione a closer view of smoother plains & tectonic faults.

Dione, a 50 KM wide crater on limb near the north pole. Saturnshine is faintly illumnatiing the shadowed areas.

Dione, a whole load of thrust faults & graben. Voyager 1 saw this terrain on the very limb of Dione & was thought to be frozen condensates. Cassini pased right over this area at optimum illumination & saw that instead of ice deposits, the wispy terrain seen by Voyager 1 was in fact massive trust faulting.

Dione Friday 5th March 2010 view from Cassini.

Dione only from 1,100 KM away. Tuesday 11th October 2005.

Dione an area approx 100 KM wide showing tectonic ridges in the ice crust, similar to some areas on Enceladus.

Section of sunset terminator in the southern hemisphere of Dione.

Andrew Brown.

 

[nimbus]

http://i233.photobucket.com/albums/ee18 ... assini.jpg
What a beautiful picture...

 

[3488]

Thanks nimbus.

That one was an absolute joy to work with, also quite difficult to keep a good contrast between the sunlit & Saturnlit regions & is one of my favourites of Dione. It is absolutely haunting.

Hopefully we'll get some more from the Wednesday 7th April 2010 pass. Only five days away now & also Titanbacklit. Hopefully there will be decent stuff I can work on & post on here. :mrgreen:

A few more images below.

High latitude crescent. Tuesday 5th October 2005. The north pole of Dione was still in darkness.

Dione sunset terminators close up. Both rotated, North to the left, East is top.

Possible cryovolcanic caldera on Dione or two shallow overlapping impact crater? Looks a lot like the cryocaldera Sippur Sulcus on the Jupiter moon Ganymede.

Dione, terminator view of tectonic ridged terrain. Image has been rotated 180 degrees, to make it easier to see.

An area, only a few KM on each side on Dione, during the very close pass on: Tuesday 11th October 2005.

A severe crop & sharpened enlargement of the limb of Dione, just a few KM wide to look like a horizon. A large rounded hill is clearly visible.

Andrew Brown.

 

[3488]

A few more Dione mugshots or image spam from me!!!!!!!!!!!!!!!!!!!!!

How's this for a crescent Dione???

Dione global view. Saturday 9th February 2008.

Dione: Saturday 30th September 2007. Equatorial to mid northern latitudes.

Dione, south polar region. Sunday 30th September 2007.

Andrew Brown.

 

[3488]

Also on Cassini thread.

Some stuff from the very close pass of Dione on: Wednesday 7th April 2010.

Remus Crater approx 70 KM wide (I think) with thrust faults running through.

15 KM wide area, I think in the Euratas Chasmata area on Dione

Enlarged crops from above. Massive thust faulting.

Interesting crater in icy surface with striations on the walls as material has slid inside.

Andrew Brown.

 

[3488]

Some more Dione spam from the Wednesday 7th April 2010 Cassini pass, courtesy of your's truly here. :mrgreen:

Dione backlit by the rings of Saturn, as about to enter Saturn's shadow. The star to the lower left I think is Ancha / Theta Aquarii.

Dione backlit by the rings as about to enter Saturn's shadow, sharpened enlarged crop.

Dione, sharpened enlarged crop of a 300 KM long section of Petilia Fossae, close to the dawn terminator.

Dione, sharpened enlarged crop of a 200 KM long section of Petilia Fossae, close to the dawn terminator.

Links to two large images I have done.

Enlarged image of 11 KM wide ice crater I've sharpened.

Enlarged 12 KM section of thrust faulting within Eurotas Chasmata, I've sharpened.

Andrew Brown.

 

[Lois_Ella]

Firstly, can I just say WOW! These are all fab! Might have to borrow a few for my classroom. I love the backlit view of Dione. Superb! Thanks for the link on Twitter really appreciate it, my students will love them too!

 

[3488]

This is only a quick chine in as I am going out. I will return on here later (as SDC members leave in droves at that threat) :mrgreen: :lol: :mrgreen: .

Firstly, can I just say WOW! These are all fab! Might have to borrow a few for my classroom. I love the backlit view of Dione. Superb! Thanks for the link on Twitter really appreciate it, my students will love them too!

Huge welcome to SDC.

I am so pleased that you have decided to join us here. I have PM'd you.

Below a NAC (Narrow Angle Camera) Cassini image of backlit Dione. It was taken at the same time as the in the post above yours. IIRC the WAC (Wide Angle Camera) has a view of 5 degrees, the NAC has a view of 1 degree.

I have enlarged the below as it was only a 512 pixel image & have enlarged it to 755 pixels & sharpened it.

Also rotated it 180 degrees so north is at top.

It is possible to make out the contours on the limb of Dione, backlit by Saturn's rings, from craters & hills. These observations were made to see if Dione has any small ice geysers, lesser versions of those on Enceladus. Why they transmitted this in only 512 pixels, I have no idea. 1,024 pixels would have been much better, to determine finer details on the backlit limb.

Same as above, but with noise & most of lens flare removed.

Andrew Brown.

 

[EarthlingX]

Thank you

 

[3488]

New maps of Dione. March 2010.

Images from Cassini & Voyager 1 were used to create these.

0 degrees marks the centre of the Saturn facing side, the 180 degrees facing outwards from Saturn. The equator is around the circumference. North Pole of Dione in the centre.
Northern Hemisphere polar projection.

0 degrees marks the centre of the Saturn facing side, the 180 degrees facing outwards from Saturn. The equator is around the circumference. South Pole of Dione in the centre.
Southern Hemisphere polar projection.

Mercator Map of Dione.

What has grabbed my attention is like Enceladus, the southern hemisphere appears 'younger' than the northern. However unlike Enceladus, Dione displays evolved terrain close to the North Pole.

It is quite apparent that Dione has 'rolled' with one of the lest cratered areas on the leading side, the area expected to be the most heavily cratered, as the leading side meets potential impactors head on.

Enceladus also shows this as do the Uranus moons Miranda & Ariel, seen up close by Voyager 2.

Andrew Brown.

 

[silylene]

Firstly, can I just say WOW! These are all fab! Might have to borrow a few for my classroom. I love the backlit view of Dione. Superb! Thanks for the link on Twitter really appreciate it, my students will love them too!

Welcome Lois_Ella.

You know, I think it could be a useful student project - if you have computers and some photo image software - for students to select images from a set of NASA planetary photos, sharpen its contrast, pick out their favorite feature (crater, rings, bands, valley) and write a short caption for each. Could be fun. At least, if I were in school, and my science teacher gave me this as a project, I would've loved it.