Going through all the MEX pics in the database mentioned over on the "Phobos" thread is like entering a hidden cave piled up to the ceiling with jewels. It's possble to make great - if low resolution - colour images out of the RGB triplets, like this...

Click to view attachment

... and this...

Click to view attachment

But some of the plain BW images are just... well... stunning... This one's been sharpened and contrast-tweaked, but I think it's one of the most beautiful Mars images I've ever seen, just because when you look at it you can't help but imagine what it would be like to stand under those wispy clouds and see them teased out across the pink sky above you by the marian winds...

Click to view attachment

But don't take my word for it. Nip over to...

ftp://psa.esac.esa.int/pub/mirror/MARS-EX...TED-V2.0/BROWSE

... and have a play for yourself!

Very nice, Stu! I managed to catch a few clouds as well with MARCI. I'm going to be doing something similar to this on a planetary scale in the near future...and I'm wondering how to automate the detection of clouds between successive images over the same region. IOW, I need some sort of change detection criteria. Any ideas what the criteria should be, in terms of programming?

Beautiful images (that last one posted by Stu must be among the most scenic mars cloud images ever



Hmm, looking at the stark contrast of those beautifully blue clouds to the reddish surface in your MARCI image, a very simplistic approach comes to mind: just comparing how the relative contribution of the blue color channel to total image brighness changes among frames ... should give an indication of the presence of those ice-rich clouds .... just a quick thought.

Excellent suggestion, Nirgal, thanks! I should have been more specific though, I'm looking for dust

I found a couple of neat HRSC images from May and June 2014 showing some really high altitude clouds. I really don't know what to make of them, I haven't seen clouds like them in Mars images before. These images are through the instrument's green filter. There are corresponding blue filter images, although for whatever reason that color channel is a lot noisier than the green. I've tried to brighten the clouds without overexposing the surface; I still need to figure out where the spacecraft was looking when it took these images...

Here's the May 11 image:

High-Altitude Clouds - Mars Express by Justin Cowart, on Flickr

And the June 5 image:

High-Altitude Cloud - Mars Express by Justin Cowart, on Flickr

In the May 11 image, we are looking eastward over Aonia Terra. The crater with a prominent ejecta blanket in the foreground is Ross. The whitish circular feature visible near the horizon is the Lowell crater. To the south of Lowell in the middle of this panorama lies Aonia Planum. Thanks for the amazing view!

Thank you for the ID! I've added it to the image description.

The June 5 image (full version) was taken looking northeast along Icaria Fossae, on the left-hand side is eastern Terra Sirenum, on the right-hand side is Aonia Terra, the large crater in the center of the panorama is Chamberlin.

A really nice image of a dust storm in Hellas, I like how the dust cloud is spilling over the rim of the basin and into adjacent craters in a thin sheet. This image was made from a blue-green image pair. The most interesting feature is a cloud that only showed up in the blue filter image as far as I can tell. (The green filter image didn't extend as far above the surface, but it didn't see anything where the green and blue images overlapped near the loop's base.) I call it a cloud because I think it might be a portion of the southern polar hood, but I'm not able to rule out scattered light or anything like that without knowing more about the image geometry.

Some nadir-pointed views from Mars Express during early 2008 (Martian northern autumn)

Wave clouds, a potential cold front, and some noctilucent-type clouds over Vastitas Borealis and Utopia Planitia in June 2013:


And a big deck of stratocumulus over Vastitas Borealis in May 2014:

Justin, These pictures are absolutely incredible. Thanks for posting them. Ron

I concur. It's work like yours, Justin, that serves as a good reminder of the true capability of the HRSC. It's not as powerful as HiRISE, but one would be lying to say that it doesn't take images just as amazing as HiRISE. I noticed in the past week you also uploaded versions of these two oblique views of Mars by the HSRC, one of the Kasei Valles and one of Olympus Mons; both of which are also amazing! The latter in particular would make for a great lead image on the Olympus Mons Wikipedia article, methinks...