I don't know abouyt anyone else, but it looks like a negative of Phoebe to me.

Few of the images show any detail at all ... is that the dreaded auto-contrast enhancement again?

http://saturn.jpl.nasa.gov/multimedia/imag...eiImageID=42159

I think what we're seeing is that all of the images that AREN'T stretched too far in this jpg form happen to be UV images. In UV, icy craters show bright rims on the other moons too. So we may be seeing nothing unusual, with crater floors that are dark only in UV. We'll have to see how the, eg, red and green images appear when they are not stretched so poorly -- they may not show dark crater floors.

The baffling thing to me is that the distribution of crater sizes appears to be so tight. Maybe this is a product of the same selection bias as I noted above, but it looks to me like Hyperion was peppered with a lot of same-size impactors. Odd.

In this sense, Hyperion reminds me of Janus, a relatively bright surface layer with a darker interior that is brought to the surface by impacts.

Unfortunately, in this case, they really are saturated The UV3 images are salvageable (and quite useful) but even they have some saturation. With the information we have gathered on this pass, we should be able to make the necessary corrections to prevent this from happening in September. The auto-contrast problem is only really a problem with bodies that are only a few percent of the frame as only 5% of pixels should have a value of 255 after auto-contrast. Beyond that, and you can assume that there is a saturation problem.

The final set of Hyperion images are now online. These show Hyperion receding from Cassini.

http://saturn.jpl.nasa.gov/multimedia/imag...1/N00035454.jpg

This image shows the region seen best by Voyager (not sure which one).

x 10^893,567,498,565,062,568



(why is there no "crying" smilie? )

Even though what I said was true, I've looked at Mimas in UV, and Hyperion's crater floors are darker than the intercrater surface (plains?), while on Mimas, the crater floors and intercrater terrain are about the same brightness, with inner rims of craters being much brigher. So Hyperion does seem to be different.

They've made lots of observations of Hyperion that seem to have come out OK, what do you think went wrong?

Here are a few more shots that came out ok

http://saturn.jpl.nasa.gov/multimedia/imag...eiImageID=42337
http://saturn.jpl.nasa.gov/multimedia/imag...eiImageID=42320
http://saturn.jpl.nasa.gov/multimedia/imag...eiImageID=42301
http://saturn.jpl.nasa.gov/multimedia/imag...eiImageID=42293

The brightness model for Hyperion was incorrectly applied, causing it to be underestimated. This led to the exposure times to be greater than they should have been. This is being resolved for September's flyby.

A lot of those little craters make up very straight crater chains, too -- just like we've seen on some of the larger icy moons, like Rhea.

In fact, a *majority* of the craters of a given size range are located in crater chains.

I'm impressed by the two chains that form an "X" in the last image on the right. Is it possible that we've found Planet X, the source of the shaving cream atom?

-the other Doug

At first I thought those crater chains might be imaginary... then I looked more closely and yes, there do seem to be a lot. But we have to be wary of our uncanny ability to see patterns in randomness. I don't think this is all random, I agree there are crater chains... but maybe not all of them are significant alignments. But let's see what the September images show us...

But despite a few scattered and disorganized grooves on Ida, Gaspra, Eros etc., so far Phobos is still unique for its extraordinary system of grooves. I would still place Hyperion more in the Gaspra class of grooved bodies, from what I have seen so far.

Phil

This is an animation of the best (UV filter) Hyperion sequence, with each frame resized in order to have same scale...
http://img91.echo.cx/img91/4821/hyperion8dl.gif

below also a couple of stereo (cross-eye) images:

The final version of my Hyperion composite...



Phil

I for one think Hyperion looks unique.

Looking forward to the next flyby.