APOD: Prometheus Remastered (2010 Apr 05)

[APOD Robot]

Prometheus Remastered

Explanation: What does Saturn's shepherd moon Prometheus really look like? The raw images from the robotic Cassini spacecraft's January flyby of the small moon showed tantalizing clues on grainy images, but now that the Cassini team has digitally remastered these images, many more details have come out. Pictured above, Prometheus more clearly shows its oblong shape as well as numerous craters over its 100-kilometer length. In the above image, the bright part of Prometheus is lit directly by the Sun, while much of the dark part is still discernible through sunlight first reflected off of Saturn. These new surface details, together with the moon's high reflectivity, can now help humanity better understand the history of Prometheus and Saturn's rings. Today, Cassini has a planned targeted flyby of Saturn's largest moon Titan, while on Wednesday, Cassini is scheduled to swoop to within 600 kilometers of Dione.

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[Slarty Bartfast]

Paraphrasing; "This must be some new definition of 'digitally remastered' with which I am unfamiliar."

[KAMRAMNA]

My answer to the question at the start of the explanation; it looks like an asteroid, a remastered asteroid that has assumed the duties of a shepard moon. I guess that slarty has equiptment that could do better, not.

[jando35]

Paraphrasing; "This must be some new definition of 'digitally remastered' with which I am unfamiliar."

If your image is too dark to make out much detail - as with mine - copy it into Photoshop and 'digitally improve' it to show all the craters, lumps and bumps.

[biddie67]

Again - distances and sizes of objects in space are so hard for me to get my mind around - that object, which looks like a closeup of a potato that has had a hard life, is some 100 kilometers long ....

What is the difference bewteen a moon and a shepard moon?

[Nest]

I wonder how these large objects formed. They are as old as the solar system, and should originate from the remnants of a super nova. But a nova can only form tiny pieces of dust of silicon, carbon and so on (I guess). How/when were they fused into a massive object? Can anyone recommend a textbook or website on this?

Best,

Mathias

[Chris Peterson]

What is the difference bewteen a moon and a shepard moon?

A shepherd moon is one which plays a role in maintaining some other structure, such as a debris ring, through gravitational interaction.

[Chris Peterson]

I wonder how these large objects formed. They are as old as the solar system, and should originate from the remnants of a super nova. But a nova can only form tiny pieces of dust of silicon, carbon and so on (I guess). How/when were they fused into a massive object? Can anyone recommend a textbook or website on this?

Presumably they formed just as the planets did: by accretion processes in the protoplanetary disc. As the gas giants (especially Jupiter) grew, they created radial zones where resonances prevented additional material from accumulating, and material already there was ejected. It isn't surprising that bodies of all sizes were present once the accretionary phase was over.

[spiral_72]

What's up with the "digitally remastered" link??? It's past April Fool's Day!!!

[Guest]

Fabulous, look forward to the Titan flyby and other shots over the next few days!

[Wayne]

You shouldn't hotlink images from Something Awful. They tend to get very NSFW very quickly.