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Posted by: jmknapp Feb 16 2006, 06:43 PM

What is the highest resolution Mars map available, preferably color?

Posted by: Phil Stooke Feb 16 2006, 06:46 PM

More info needed! MOLA topography? Approximately true surface color and albedo? Both combined? Did you want digital, or a published paper map? Does the projection matter?

Phil

Posted by: jmknapp Feb 16 2006, 06:57 PM

Something along the lines of the MGS/MOC or the Mars Express visual camera. Digital, cylindrical projection.

MSSS has a very hi-res map in black and white. The MSSS web site says they are working on a color version, and some kind of combined MOC/MOLA, but I think that hasn't happened--at least I couldn't find them there.

Posted by: Phil Stooke Feb 16 2006, 07:39 PM

Try this:

ftp://ftpflag.wr.usgs.gov/dist/pigpen/mars/usgs/mdim21/jpeg2000/

more info here:

ftp://ftpflag.wr.usgs.gov/dist/pigpen/mars/


from the USGS planetary GIS site. They do say "Please browse our Mars GIS FTP site for files that have not yet been linked." so you can poke around in here.

But no color yet.

Phil

Posted by: mcaplinger Feb 17 2006, 12:26 AM

That's true, we haven't completed that. Our MRO, MSL and LRO work has cut into the hobby time I used to make the B&W mosaics, and the color mosaics are much more labor-intensive to make.

http://www.arcscience.com/face.htm has a colorized Mars map, but it appears to be a commercial product.

Posted by: jmknapp Feb 17 2006, 01:36 PM

The sheer amount of data is amazing. Your 256 pixels/degree map is multiple gigabytes, but even then is only a fraction of the MOC resolution. I'm looking for a map from which to generate simulated HiRISE views, but 256 pixels/degree at the equator works out to 232 meters/pixel, compared to the HiRISE resolution of 0.30 meters/pixel. For the 1.14 degree FOV, the 256 ppd map at 300 km altitude affords about 26 pixels across, compared to 20,000 for HiRISE. Of course, I shudder to think of how many bytes a full MOC resolution map would entail, and the amount of work involved making it.

Phil: Thank for the links. I'll have to read up on that JPEG2000 format. I tried a couple of programs that are supposed to read that format but they both bombed out with a Windows unrecoverable application error when trying to read the images (over 200 MB JPEG2000). Maybe I need more than 512MB RAM!

Posted by: djellison Feb 17 2006, 02:11 PM

There used to be a 20k wide map at maps.jpl.nasa.gov - but it seems to have vanished.


mc's great map is, iirc, MOCWA - and thus never going to be much more than 250m/pixel - and there's very little coverage, globally, with MOCNA, which would be down at the 1.5->5m/pixel range - so a map couldnt be done at that res.

I wonder what could be done with Themis imagery

Any idea if CTX and MARCI imagery is going online in the same fashion as HiRise?

Doug

Posted by: Bjorn Jonsson Feb 17 2006, 04:50 PM

What would be particularly interesting (at least for me) is a map without shadows (really an albedo/color map). This is useful for use in 3D rendering in conjunction with the MOLA data.

In theory, this map could probably be made from existing colormaps by setting the luminosity (in hue-saturation-luminosity) to a constant value for the entire map. A big problem with this is that some of the shadows are very dark or black so there is no useful color information in the shadows.

Posted by: jmknapp Feb 20 2006, 03:15 AM

I'm curious as to why the gap in the data between 60-65S? something to do with the geometry of the MGS orbit?

Posted by: mcaplinger Feb 20 2006, 03:55 PM

The basemap used for the mosaic (a hand mosaic of global map swaths) wasn't useful south of 60S. While the actual Geodesy Campaign data goes down to 65S (it was taken during southern winter so areas south of there were in darkness), the basemap control rendered the area between 60S and 65S too dark to use. And the south polar coverage we took later started at 65S.

This could all be reprocessed and fixed, and it's on my list of things to do, but not very close to the top.
The gap was fixed for the "Mars Atlas" but that was only produced at 64 pix/deg -- see http://www.msss.com/mars_images/moc/moc_atlas/

Posted by: vikingmars Feb 22 2006, 05:05 PM

Here is your link for Mars maps to download :
http://www.celestiamotherlode.net/catalog/mars.php
Enjoy !

Posted by: jmknapp Feb 24 2006, 03:07 PM

Thanks... very nice maps there up to 16k (45 pixels/degree). I'm going to try to make an MRO sim that uses those maps further out & then mcaplinger's maps (up to 256 pixels/degree) closer in. Here's an animation of the approach & first two orbits using praesepe's maps from the Celestia link:

http://cboh-t.cboh.org/~jmk/mromoi_snd3.mpg

Still working on crunching mcaplinger's 256 pixels/deg map tiles into small tiles--they are a bear, up to 600MB each and 4 gigs total.

Posted by: Bob Shaw Feb 24 2006, 05:27 PM

For a horrible moment at the end of the sequence I thought there was a SPLAT!

I was s-o-o-o-o-o wrong!

Bob Shaw

Posted by: jmknapp Mar 6 2006, 11:50 AM

The THEMIS IR images from Odyssey seem very detailed. Have they been compiled into a global map?

Posted by: Phil Stooke Mar 6 2006, 02:03 PM

Not yet but will be.

http://astrogeology.usgs.gov/Projects/THEMISMosaics/

Phil

Posted by: jmknapp Mar 6 2006, 05:11 PM

Very interesting... thanks. I guess it will be a while. I had thought that maybe this work was already done, because the http://webgis.wr.usgs.gov/website/mars_html/viewer.htm uses THEMIS imagery down to a very high resolution. Maybe just not to the accuracy talked about at the link above?

Posted by: mcaplinger Mar 6 2006, 05:38 PM

With all due respect to my colleagues at USGS, I think this product will take them several more years to produce. I think one should expect a product from ASU before that.

Of course, the IR resolution is "only" 100 meters/pixel. THEMIS will probably not obtain global coverage at VIS resolution (18 m/pxl), or even 2x summed VIS (36 m/pxl.)

The next thing to hope for will be a CTX global mosaic at ~12 m/pxl.

Posted by: jmknapp Mar 6 2006, 07:20 PM

USGS, ASU, MSSS... looks like the race is on...