I seem to recall that clouds have been observed over Cimmeria for a long time, even back in the days when it was Mare Cimmerium and observed only through feeble terrestrial telescopes.



-the other Doug

My surprise isn't the clouds forming over high topography in high latitudes, it's of finding a cloud that seems so localized. That little guy is always there at sunrise.
(The Sept. 7, 2008 MEX VMC images have yet another really nice sequence of clouds in the same location (5/5!) that I'm currently working on.)

The USGS altimetry map of Mars (links to immediate 2.1 Mbyte PDF download) shows two local high areas next to and running south of Cruls and Bjerknes Craters, with the cloud seeming to form in the area between them. Assuming the upper atmosphere circulation is aligned with the winter high latitude eastward jet (Britannica ref here), it would seem that the Bjerknes ridge might be causing a downwind upper atmosphere rotor.

*I think*

-Mike

BTW, if anyone has any lit refs on observations of Cimmeria clouds - please let me know. (Along with the Conan literature - I didn't find any specific articles - but a lot of general observations)

These clouds are not obvious in the MRO MARCI movie for the week September 1-7, 2008 (available here) . But these are in the southern edge of the movie area (and maybe these clouds are only evident at sunrise?)

Animated GIF showing the September 7, 2008 sunrise clouds of Terra Cimmeria:
Click to view attachment
(click to animate GIF)

This uses both the longest and second longest exposure images (I adjusted the exposure level so they would match up). Interesting to see the two clouds closest to the daylight portion fade out either due to dissipation or lack of sufficient contrast against the brightening background. Also cool how the sun starts lighting up clouds further back as dawn progresses. (Would be neat to see this from the surface, probably really pretty).

-Mike

[Please ignore the things shooting across the surface from lower right to upper left, those are camera artifacts I wasn't able to totally remove after contrast enhancement.]

Montage showing the sunrise clouds near Bjerknes Crater for the 5 observations between July 7 and September 7, 2008.

Click to view attachment
(click to animate GIF)

Images are all centered on Copernicus Crater, I tried to correct for rotation and viewing angle as best I could. The image used was the last, longest exposure image on the observation day. No contrast enhancement or additional exposure correction was used.

-Mike

Hi all, looks like some brilliant work is going on as usual - once again my congratulations on pulling so much from the VMC images! Just by way of a quick ops update, we've got another two or three nice observations which should be going online soon, some with some interesting linear(ish) surface brightness features you might be interested in checking out.

For the things that have been posted here - first off, Doug - the spinning volcanoes - would love to post that on the VMC website, if you could just add the information that's at the bottom of the "Help us with VMC" page and stick that on an e-mail to us that would be great on the site.

For the clouds work that you've been doing Mike - it's a really interesting study into our little "Cloud Factory" that we've found. I don't know how much longer we'll stay over this area - I guess the orbit evolution will move us away eventually. When you've got enough info though if you want to put your animations, images and plots together with text explaining all you've found and maybe referencing other texts, we could post an article on the VMC website about the VMC cloud factory at Terra Cimmeria!

Ok...new images are up on the site! That strange-ish feature I'm talking about might just be normal Mars terrain (just the first time we've seen it with VMC). You can see it in the images on the gallery here: http://esamultimedia.esa.int/multimedia/vm...9.34/index.html. It's the band stretching across the bottom right of the disc - possibly an albedo feature? Always look forward to your comments!

What happened? Nothing in nearly a month.

Hi! Sorry for the downtime for a while - we do have quite a few new images in the queue that are just waiting to be uploaded to the website. Daniel, who manages the website had a holiday in October and is clearing his other work before getting back to VMC.

Unfortunately VMC will be taking its winter holidays for 3 months from next week. This is due initially to the solar conjunction, where we shut down all payload ops on the spacecraft for a month. Then for the 2 months following that there are perfect optical conditions at our pericentre which means HRSC will be taking lots of images. With Mars far from earth though the bit rate is low so we'll be filling our downlink with data from the science instruments. As the conditions change though and the link margin improves VMC will be back with enthusiasm for its 2009 campaign. First up is our coming eclipse season, starting March 2009, which should give us "Crescent" conditions once again (for all those crescent fans out there!). Keep watching!!

Thanks very much for the update. I do look forward to the return of crescent season!

I am sure you already know this, but if there is any "grunt work" to be done in whatever Daniel needs to do to prepare images for posting, I can speak for myself at least when I say that there are probably willing volunteers available here.

--Emily

Thanks for the offer! I think we should be able to cover the prep work of getting the images online (we literally throw the raw results up), although in our 3 month break we may try and streamline the process.

What would be interesting though, and I think we'll try and publish something about this, is coming up with VMC's "Best of 2008". We created the "Best of 2007" (http://www.esa.int/SPECIALS/VMC/SEMZVSXIPIF_mg_1.html) just before we launched but would be great to open it up to the community to choose our "Best of 2008", probably highlighting any colour/animation/sharpened/post-processed works from the public gallery (do keep contributing to that)!

Definitely looking forward to crescent season too, hopefully we'll pick up some more cool cloud action. We'll also see with Flight Dynamics if we can update the pointing we use to track Mars, so it doesn't slide off the edge of the image. There's always fun new things to do on VMC (although I should concentrate on helping get MEX through conjunction first)!

Ok...we're officially offline for the time being!! In addition to what's on the website I'd like to wish UMSF a Merry Christmas and Happy New Year and hope you'll be back with us and VMC next year. Check out the website for details of what's coming in 2009 - hope it's going to be an exciting year. Also please send in your suggestions or submissions for best of 2008!

Hi again! The Mars Express VMC is back! We've resumed imaging operations since the middle of February but have been working on a new website. I hope you'll all like the new and improved website, which we've moved to the ESA blog system. This gives us the ability to be more interactive, you can comment on new image sets or on posts by Daniel or I and we can respond right there.

Most exciting though is that this system allows us to use an automated image upload tool, so no more waiting for the images to be posted! After the images are captured by VMC they're stored in the spacecraft solid state mass memory and then wait for a slot to be dumped to Earth. Within a few minutes of them arriving at the ground station the software will pick them up and post them to the blog. Unfortunately waiting for the dump slot could be as long as a week but in some cases could be less than an hour - now we're in real webcam territory! That means too that you could be seeing images of Mars for the first time, before anyone on Earth has seen them!

So...I hope you enjoy, unfortunately the VMC schedule for April is only two observations but May will bring a packed schedule. Do stop by the new site, comment and say hello, and look at the latest batch of Mars crescent images!

Wonderful!! And its great news about the new image handling and blogging.

Big improvement on the outreach that I think everyone hear will be delighted to see!

Nice one.

P.S... Can you put a link to the site in your signature?

Glad you like it, I've updated my signature now, thanks for the idea!

Hmmm. I am unable to get any of the MEX VMC Celestia scripts to run. After putting the .celx file into the 'scripts' folder and trying to run from Celestia, I get a fatal error that causes Celestia to crash.

For example, for the March 19th Celestia file (available here)
When I try to run it, the error states " [string " scripts/2009-03-19_19.25_19.30.celx"]:5: unexpected symbol near '/' "

I'm running Celestia version 1.5.1.

Anybody know what I'm doing wrong?

I don't know Celestia per se, but I do know computer formats.

This file appears to have been "escaped" for some reason. Special characters have been prefixed with an escape character, '\'. Notice the instances of '\"' and '\\'. I really doubt Celestia wants it escaped in such a way. It's needlessly verbose for a script file.

Try opening the file in your favorite text editor, and doing a global search and replace, turning:
\" into "
\' into '
\\ into \

And any other escapes you might notice. Save that, and give it a shot.

Thank you! That did the trick!!

-Mike

I took the March 19th images and masked out the overexposed image portions to allow the cloud detail to come through. (Full details here)

Here is the before and after:
Click to view attachment

Using the corrected Celestia script (thanks, maschnitz!) to coordinate the image, it turns out that the image is centered high over the martian north pole, with the Phoenix Landing Site in twilight near the center of the terminator:
Click to view attachment

-Mike

It is almost possible to correlate the processed MEX VMC image with a frame from the MARCI movie for March 16-22, 2009.
(MARCI movie is available here: http://www.msss.com/msss_images/2009/03/25/)

The lower portion of the MEX VMC Cloud Detail image matches up with contrast-enhanced image of the uppermost portion of the MARCI still from March 19,2009:
Click to view attachment

There is a swatch of a cloud band stretching SW to NE (yellow) bounded by two darker zones (blue arrows).

So the MEX VMC image complimented the released MARCI image for March 19th.

Cool!

-Mike

Are you sure there's not some Venus Express data in there? The swirly clouds look a lot like Venus to me.

Hi all!

Thanks once more to Mike for his great work on the 19th March images, please do leave a comment on the VMC blog to show your appreciation! I'll hopefully get a chance to add some of the bits he's posted here too (if that's ok Mike?).

Thanks too for the troubleshooting of the Celestia script. It seems to be a problem with how the scripts are processed by the blog software (they're fine before upload). I'll try and get to the bottom of what's happening and get it fixed as soon as I can. I know the scripts are quite verbose but I wanted to make it as accessible and easy to use as possible for those that might not be familiar with VMC observations or with Celestia. As always though, any suggestions are very welcome!

Last thing...you'll notice there are some new images now from 19th March, and the 20th March (they were waiting on board for a dump opportunity). There's still some data from the 20th March left on board, that should come along with a new observation on Saturday. Next Thursday though we've got an observation with a dump same day - those images (assuming all goes well) should be online right after...hot off the spacecraft

P.S. Haven't shown the images to our Venus Express colleagues yet...let's see if we can make them jealous..promise I didn't steal them from their VMC!

Absolutely! Let me know by PM or e-mail if there's anything I can do to pretty them up!

-Mike

April 9 image enhancement of what I think might be Alba Mons.
(Celestia pointing information was kinda strange - according to Celestia, Mars should've been gibbous)
Click to view attachment

To make the image, I stacked 3 images (09-099_05.09.13_VMC_Img_No_15.png, 09-099_05.05.40_VMC_Img_No_11.png, and 09-099_04.58.33_VMC_Img_No_3.png). No. 15 was the base image, and a fuzzy layer mask was made for the interior section of the crescent. The images were then averaged to help get a better S/N. (No. 11 opacity 50%, No. 3 opacity 33%). Then the combined region around Alba Mons was selected and a white to black gradient was created. This gradient was subtracted from the region around Alba Mons using the Apply Image function. This section was then contrast enhanced, and a mask used to add this to the original combination. [This is the technique I've been using for the Titan images]. An Unsharp Mask was done, and finally, the whole thing was contrast-enhanced with a Curve.

Here's a comparison of a contrast-enhanced crop of Image No. 15 compared with the result from the recipe described above:
Click to view attachment

(Spacecraft motion and the changing of the perspective made the borders of Alba Mons fuzzier but better S/N. The layer mask set from Image 15 kept the crescent image crisp.).

-Mike

[Alternatively, I guess that dark spot above could also be Arum Chaos]

The image was taken April 9, 2009 05:02:06 UTC.

Any guesses?

The May 2009 MEX VMC images are all nicely taken at about the same distance (thus have the same size) and all appear centered close to the N Pole (based on cloud banding). The crescents are all oriented similarly also.

Here is an EXCEL table of the MEX VMC image crescent midpoint longitdudes for the May images:

Click to view attachment

(I was using this to see if I could pull off a multi-day movie of clouds centered on the same location. No luck!)

Here is a rotation sequence study of the May 27-May 30 MEX VMC images sequenced according to shifting westward longitude of the crescent midpoint.

Click to view attachment
(click to animate)
(Mars appears rotating underneath, the images are NOT in time sequence)

The first image in the sequence shows how Alba Mons really makes cool clouds. Olympus Mons is the dark circle spot, Alba Mons is to the upper right, the extra-bright clouds are to the NE of Alba Mons. (Right near the lens artifact )

A cool one from a couple weeks ago:

http://webservices.esa.int/blog/post/6/774

MEX VMC image of a possible cloud or bright albedo feature near Hesperia Planum taken on August 15th, 2009:
Manually blended set of four differently exposed images then contrast enhanced.

Click to view attachment

(Full resolution processed image here: http://www.flickr.com/photos/31678681@N07/3867648999/)

The July 11 2009 MEX VMC image shows the cloud near Arsia Mons is still present (far left near the terminator).

Here is a composite:
Click to view attachment

Latest images show a large cloud complex and a cuter bunch of clouds to the (S?):

http://webservices.esa.int/blog/resource/6/8360

I'm wildly guessing the large complex is near Acidalia Planitia. Hard to tell with few surface features.

I tried to pull of a "super-resolution" image from MEX-VMC images taken on July 11.

I thought that two images from slightly different perspective might be able to generate subpixel resolution. Turns out that the 3 minutes between shots with similar exposure levels is still enough to radically change the perspective, making it not worth the effort. S/N got helped a little bit, tho...

Results here: http://www.flickr.com/photos/31678681@N07/3942553995/

(Link to "super-resolution" technique: http://www.lpi.usra.edu/meetings/LPSC98/pdf/1817.pdf)

[I credit Ted Stryk's blog for pointing me in the correct direction for this image technique.]

There's something weird in these photos that's not visible in photos from days before or after -- what I assume are high-altitude clouds beyond the terminator; and is that a pile of clouds above the pole?

We're certainly seeing some interesting cloud dynamics during this "crescent season" on VMC...as always you are our scientists and investigators on VMC so if you want to submit any analysis or favourites please e-mail us and we can add it to the site!

I also wanted to flag that we've got some great observations that just took place and some more coming up. First off...for the next few months the time between image capture and dump to earth (which triggers the website upload) will be reduced by a lot. Some images have gone online within a couple of hours of being dumped!

We've also got some lower altitude images, such as these two observations:

http://webservices.esa.int/blog/post/6/912
http://webservices.esa.int/blog/post/6/913

These are showing some really nice surface detail, and are being captured with a tightened exposure range and less time in between images. There should be some more coming up soon, including one looking at the limb for cloud activity (although I think you can already begin to see limb clouds in the galleries above).

Finally, an apology and an update on the Celestia positioning scripts on the website - these were being based on an old planning reference which is why they were sometimes not matching well with the actual observation. This has been updated now and all recent and coming observations should be correct. I'll try and systematically update the old observations but if there are any particular ones you need do let me know.

So should be a fun Christmas for VMC, as always I look forward to your discussions, comments and results!

Thanks, ormstont!

For those of you who've been doing work on the VMC images, have you developed any specific workflow for boosting the Mars-like color in these images? Is it just as simple as increasing the saturation or do you do any channel-specific processing?

--Emily

I've been fiddling a bit with this problem. I don't think I've found the best solution yet, but here's a few tries -- I'd welcome opinions, as although I've done a lot of work accessing raw images, I haven't spent much time trying to get colors to look right and I feel sort of as if I'm wading into deep water here.

Version 1: Just fiddled with levels to try to make a bright spot turn a Mars-like orange.
Click to view attachment

Version 2: Jacked up saturation, then levels.
Click to view attachment

Version 3: Channel mixing: red = red minus 50% blue, blue = blue minus 50% red, green stet, luminosity constant.
Click to view attachment

Version 4: Channel mixing: red = red minus 50% blue minus 20% green, blue = blue minus 50% red minus 20% green, green stet, luminosity constant.
Click to view attachment

Not sure what to try next...any suggestions?

--Emily

Wow! Especially the last one looks very cool. Maybe with some destripping technique that can be even better.

Getting rid of the stripes would be nice. Can you suggest any specific workflow in GIMP or Photoshop that would reduce that effect? Or any other software out there?

--Emily

Here's what that same channel-mixing algorithm as in "version 4" above does to a half-phase photo containing the Tharsis Montes.
Click to view attachment

And heres's that same image, except this time I subtracted 20% each of red and blue channels from the green. I think I'm beginning to get too cute with all this channel mixing though. I differenced the two and found almost no difference between them.
Click to view attachment

--Emily

What the heck is that angular smudge shape in the lower right quadrant?

It's a camera artefact, there's some funky internal reflections and god knows what else going on with it.

It reminds me of an emulsion tear on the old Cibachrome photo paper, (1970s before you kids were born.)

I've long been contemplating a flatfield for the camera, but the trouble is it's not trivial to generate one from non-blank images such as we get. I wasn't also sure if it would make much difference. Turns out it does help, as an exercise I stacked 6 or so recent frames and selected a (small!) portion of the resulting image that provided best noise reduction as a makeshift flatfield. Here's a comparison of an image without this section multiplied out (though in photoshop which does not do proper multiplication AFAIK). See if you can figure out which bit was flatfielded:

Click to view attachment

The "flatfield" still has some residual surface details from the original image and is obviously not spatially uniform. If I pursue this further and it turns out good, I may add automatic flatfielding to the vmc2rgb tool.

I wonder if there's an observation we could request that could emulate a flat-field.

This is my post VMC2RGB efforts for a few 2009 sequences.

Just realised some of the movies are stupidly long - but the motive behind making them .movs was that in quicktime you can scrub backwards and forwards really easily.

about the only thing in gimp 2.6.7 would be the gimc "graystrastion"

there is an isis3 way
run a highpas with something like 301x 3
and a lowpas with 3x33 and add then together in algebra
play with the two boxcar sizes

It's a definite improvement. The area most affected by the flatfielding also appears smoother -- I thought that was all noise, but does the success of the flatfield suggests it would be something that could be flatfielded out?

Please please add into vmc2rgb!

--Emily

Why have I not been playing with this stuff more. There's a lot of crescent obs that i just don't think are recoverable to being particularly attractive - but some stuff earlier in the year was awesome

Attached - rolled-out action of my saturation + channel tweaking post vmc2rgb

What logic led you to that channel math, I'm curious? Or was it just the result of fiddling? My thinking was that if there was bleeding from one channel to another, then I ought to subtract the extreme channels from each other...

Pure artistic tweakery.

It's noise, but it's static noise for the most part, indicating it's down to individual pixel sensitivities. Which can easily be corrected given an adequate flatfield. I don't think other noise sources even begin to matter in such a simple, 8 bit camera.

The difficult bit is not adding an algorithm for this into the tool, it's creating a flatfield in the first place.

I wonder if by virtue of imaging far closer to mars, on more featureless areas, possibly during dust storms - we might be able to generate a flatfield of some sort.

I'm also wondering if it's worth suggesting to the VMC team that they could well avoid the four different exposure settings, stick with the 2nd of the 4, typically, and either quarter the downlink, quadruple the frame rate, or quadruple the observation duration. There seems to be a pattern of one under exposed, one slightly over exposed and one saturated image for every well exposed image. It's not like we're going to be pulling HDR images out of this stuff.

If we can then constrain observations to that one exposure setting - then we can have just one dark field image, one flat field image, and be much better equipped to process the images.