Rev 175 - Nov 19-Dec 3, 2012 - T88 and Saturn's north pole Options

[volcanopele]

Images from ISS' observation of Saturn's north polar region are in:

NAC: http://saturn.jpl.nasa.gov/photos/raw/rawi...?imageID=274011
North pole pretty much looks like the south pole of Saturn
WAC: a hexagon http://saturn.jpl.nasa.gov/photos/raw/rawi...?imageID=273947

[elakdawalla]

That sequence is unbelievably spectacular. The CB2 images of the pole...I swear I'm seeing vertical relief but it could just be an optical illusion. I fiddled with trying to take out the rotation by stretching the pole to a circular shape and then rotating the frames to align some features (you can't align everything because of differential rotation) but I couldn't make it work. Hopefully someone with greater skill here will take up that challenge...

[antipode]

Thats the image of the year - right there (actually - yes, go look at the whole sequence, its amazing).

I remember being gobsmacked by the south polar 'eye' images, but these are clearly at a much higher resolution and at beautiful sun angles.

All that convection! I wonder if someone can figure out the vertical relief of those cloudtops?

However it still looks different to the south pole, the spiral inside the 'eyewall' here seems quite different to the calmer looking area with 'popcorn' convection inside the southern eye. Maybe its just because theyre better images, but I dont think so...

I hope someone does a rotation movie - I'm stuck at work!

P

[machi]

Simply gorgeous!
And it's very nice sequence indeed.

[t_oner]

take up that challenge...

I tried this with the best tools in post production, but the frames are not enough to create a satisfactory result. Maybe Machi's manual method will work.

[Ant103]

Simply amazing ! Theses NAC view are just mesmerezing. I will try to make an animation of it.

[Hungry4info]

I swear I'm seeing vertical relief but it could just be an optical illusion.

I'm pretty sure it's real. In some places you can see shadows of clouds and you can take a stab at the height of some of the clouds from that.

[Ant103]

My try to make a reprojected animation, with some smoothing between frames. But yes, there is not enough frame to do something smooth.

http://www.youtube.com/watch?v=dMsGxIkxlUk

[Bjorn Jonsson]

Absolutely amazing images.

That sequence is unbelievably spectacular. The CB2 images of the pole...I swear I'm seeing vertical relief but it could just be an optical illusion. I fiddled with trying to take out the rotation by stretching the pole to a circular shape and then rotating the frames to align some features (you can't align everything because of differential rotation) but I couldn't make it work. Hopefully someone with greater skill here will take up that challenge...

The CB2 image has a resolution of ~3 km/pixel (maybe a bit better) so seeing vertical relief might be possible. Something like ~30 km vertical relief (that's what I get from very crude 'measurements') does not seem implausible given what's known about Saturn's cloud layers. The sun is also coming from the right at a fairly low angle and the appearance of the clouds seems consistent with that. *But* - what we're seeing might be partially or entirely an optical illusion as noted above - the color/brightness of different clouds is variable and the image is heavily contrast stretched. But it's also interesting to note that vertical relief is visible in Voyager images of Jupiter at significantly lower resolutions (~15 km/pixel) and Saturn's atmosphere isn't as 'compressed' vertically as Jupiter's thanks to Saturn's weaker gravity (the scale height of Saturn's atmosphere is higher and the altitude difference between different cloud layers is bigger at Saturn).

In fact it just might be possible to extract some vertical relief information from these images by using two of them as a stereo pair and by correcting for the zonal (east-west) winds. The interval between the images has to be short though and the shape of the cloud features must be fairly stable over that interval.

I've been experimenting with this using two Voyager 1 images of Jupiter as a stereo pair with mixed results. The resolution of that data is significantly worse than here. The resulting 'DEM' reveals a change in the height of cloud features roughly where expected (lots of noise though) but the change is the opposite of what I was expecting and I think my software is detecting latitudinal variations in the zonal wind speed and not vertical relief. I should probably clean this up a bit and post it in the Jupiter forum.

[paraisosdelsiste...]

There are some in colour. As usual, a gorgeous Saturn

[kemcab2012]

This is a first pass, rough draft done in Gimp (Photoshop's at home).**




**Blame it on my ignorance of the app, but I didn't immediately find a way to perform scaling/perspective/and rotation all at once within Gimp. On top of that, when performing transformations on images, whatever layer you are on immediately overlaps all others, so you can't adjust beneath another layer or within a painted selection. Therefore, the destructive nature of each individual change rendered the overall result a bit on the blurry side and not in perfect sizing. I'll create a cleaner version without as much distortion and blurriness when I have access to Photoshop (which should be later tonight).

[elakdawalla]

AWESOME. That is exactly what I was trying to do. Can't wait for the Photoshop version.

[belleraphon1]

Incredibly beautiful....
how I would love to glide through the cloudscapes of Saturn just as we rove the rockscapes of Mars...

Craig

[kemcab2012]

Here's a cleaned up version of the above.

[Ant103]

Wonderful Kemcab !

From my side; I've been playing with a reprojected version of one picture, and use it as a bump map. Here's the anaglyph version. Looks pretty accurate for me (of course, vertical relief is exagerated).

Attached thumbnail(s)