new and unexpected images from MESSENGER arrived today !
http://messenger.jhuapl.edu/gallery/scienc...mp;image_id=448

Erwan

Rick,

see the code below.
The files produced are very large, but I guess that the way it is with the STL format. For such well-defined uniform grids, it seems quite overkill though. A 2400x2400 grid converts to 11,520,000 facets and ~550MB.

Erwan

Rick,

The IMG file is probably the best to use.
I could do that pretty easily with Matlab (and probably the open-source Octave can do it similarly).
Basically, I read the IMG as an int16 array, divided the values by 2000 to scale to km, created X/Y arrays (see the LBL files for the relevant info). Then, I used a script on the Matlab File Exchange (http://www.mathworks.com/matlabcentral/fileexchange/4512-surf2stl) to convert those 3 arrays (x,y,z) to a binary STL file (it can also do ascii).
That last step is pretty slow, so I actually created a STL from a small subset region of the IMG file I was trying out (LDEM_75N_240M.IMG).
I tested it out with MeshLab (http://meshlab.sourceforge.net), and it seems to be working fine.

Erwan
(I'm not including the (short) code I wrote because you might not be using Matlab, but let me know if you're interested.)

I added shaded-relief images from 4 different lighting azimuths.


That's very close to the raw IMG files, no? I added grayscale images (PNG, JPG).


Erwan

Hi All,

Some LOLA products for the PDS release (#5), which will be officially out on March 15, 2011, are now available on the LOLA PDS node !
Label files and documentation are still being worked out, but I thought it'd be good to post (and some of you know we usually put those products online a bit early)

The data released are from July 13, 2009 to January 31, 2011.
There are EDRs/RDRs (individual profiles) for the courageous ones. But most of you will prefer the map products ( http://imbrium.mit.edu/DATA/LOLA_GDR/ ).
In addition to IMG products (int16), there are JP2 files (GeoJPEG2000) which are compressed (lossless) and contain projection information. If you use a GIS programs, that should be helpful. The attached XML files contain the statistics already, which could save you 10+ minutes for the bigger grids upon loading. (Due to PDS filenaming conventions, you need to rename them to file.JP2.aux.xml for that to work properly; tested on ArcGIS).
And keep in mind that in both those formats, the data were digitized at a 0.5m granularity, so you will need to divide the values by 2 to get the actual heights (in meters).

Also of interest for visualization are the updated LOLA texture packages for Celestia.
ZIP files here: http://imbrium.mit.edu/EXTRAS/CELESTIA/
and a few screenshots:







It'd be great also to know how this community is using the LOLA data, so please reply if you do:
1- Experimental Data Records (EDR) [raw telemetry]
2 - Reduced Data Records (RDR) [altimetric profiles]
3 - IMG Gridded Data Records (GDR) [maps]
4 - JP2 Gridded Data Records (GDR) [maps]
5 - Celestia Virtual Textures


Enjoy !!

Erwan

EDIT 2011.02.25 08:30pm EST
I realized there was a mistake in the level 0 normal map. (The files were the same as the topography texture...)
The ZIP files have been updated. In case you downloaded the "old" version, you can download the two level 0 files here instead of re-downloading the ZIP.

Current orbits are good to 15-20m, so I am not surprised that the orbit errors show up at 5m resolution. We're working on it (for example, by developping new gravity field models), but 5m is currently not achievable. (For reference, the original requirement was 50m). Maybe after GRAIL gives us a perfect gravity field!
Also, keep in mind that each laser footprint is ~5m in diameter, so your maps will have very sparse coverage at those resolutions.

GeoJPEG2000 are forthcoming. We want to make sure they're correct, and we found some strange things happening with the programs used to make the conversion.
Anyway, release date has always been the 15th, if you can wait that long

As for the 128ppd being too large, we did not plan on splitting those up, but that could potentially be done in the next release, if enough people think it's worthwhile. The problem is that when we eventually release a 1024ppd, we don't want to break them up 256 tiles (each equivalent to a 64ppd global). 64 "128ppd" tiles will be quite enough already!

Erwan

Here is one image of the South Pole region as shown by Maria Zuber in the Ames meeting about a month ago. Click for higher resolution.

It's a 25-m DEM constructed from ~4000 profiles. The axis labels are in kilometers (stereographic projection around 0,-90).
Still a few blemishes, but impressive enough I hope

Erwan

CDEM contains the counts. LDEM contains the altitude (discretized in half-meter levels).

Erwan

James,
we discussed that offline, but I do not agree that we need to paint the whole Moon to have a realistic map at say 25m resolution. Indeed the current filling ratio of the 25x25m near the poles was 72% when we discussed that in June, but it will keep on improving.
The September release in a couple of weeks will have side products for each of the DEMs containing the counts of laser shots in each pixel. People can use that as a mask to see where you can be more or less confident in the measurement averaging (actually a median).
But I am not sure that is what will capture the interest of most people here. And having "gaps" in the DEMs to reflect the actual sampling would not necessarily make it better; I would expect most people want a full map, and do not want to do their own interpolation (they may not be familiar with the tools to do so) when they want to render a given region.
To reassure you, the data is not put through magic black boxes, and the workflow is actually pretty straightforward. It just gets messy to deal with when you have billions of points and those high resolutions.


Do you mean globally? In June, polewards of ~85deg, we had ~90% coverage at that resolution.

All,
The September release is coming very soon, and the DEMs will be updated this time, with more than 2 billion (good) points which went into them.
I updated the Celestia products, and they are already available here: http://imbrium.mit.edu/EXTRAS/CELESTIA/
They were made from the to-be-released 128ppd grid. Annoying seams should be gone (note to djellison and John). We are also releasing a 256ppd map (in four tiles), but I do not have the time currently to do it from that source (that would bring us to level6). And currently, it might be overkill. Others are welcome to try it out!

As for the new polar maps you saw in Maria Zuber's Ames presentation, this is not exactly what is going to be released. I'm not going into details here, but basically, the PDS release will still show some (reduced compared to before) orbit streaks near the poles. I will try to provide a better image of the South Pole, as it seems to be of interest here

Erwan

The website with the Celestia textures has been updated with improved textures (new ZIP files).
Seams that were visible at 10-degree latitude interval are now gone, and the color scale for the false-color image has been changed.
There are still some minor issues with the normal map (equator, 0 longitude), so they may be further updated, but not immediately.

Erwan


screenshots (click to enlarge; large files ! ~4Mb, 2560x1600)

John,

Nothing is 32bit except the GRDs.



Jim,


This seems sensible. I will double-check tomorrow and correct it.
We are working on improving the labels in general. Very soon you'll have one label file per product format (jp2,img,grd).
Bottom line, I think LDEM_64.LBL is correct.



Good to see people integrating the data in their program already
On that website you say "Nonetheless, LOLA gridded data covering the period 2009-07-13 through 2009-12-17 are (unofficially?) available on an MIT website." Actually, this MIT website is the official LOLA PDS data node. PDS archives/mirrors it.


Emily is perfectly correct in her post. We don't want to take the Kaguya data at face value (even though they've done a good job) and simply put them in. The LOLA data are geolocated based on LRO orbit solutions, which we understand and are working on improving... And with time, we'll cover (very close) to those Kaguya tracks.


I think all your answers will be found in :
ftp://naif.jpl.nasa.gov/pub/naif/generic_...orientation.pdf
If you're familiar with SPICE, basically, in addition to using the "de421.bsp" kernel, we also load the following kernels, which define the "MOON_ME" frame.
moon_pa_de421_1900-2050.bpc, moon_080317.tf, moon_assoc_me.tf, also available from the NAIF website.


well, you can see that as superficial; but it's just recalling what is in this dataset, so that people know it's not geoid-related ("huge discovery: lava flows going uphill!"). We may release planetopotential topography grids in the future. Plus, in the RDRs, the geoid value at each LOLA point is defined.


Erwan

John...
as I noted earlier in response to mhoward, there was an issue with the cylindrical IMGs being unsigned instead of signed. This was corrected. Did you see that, and are talking about the IMGs currently on the website?


I personally haven't tried with the IMGs, but the JP2s seem fine when overlaid over a Clementine basemap. What do you mean by "way off" ?

Erwan

actually, thanks for finding that out (and reading the doc first ). The cylindrical IMGs had a problem. They should now be fine (signed int16), so please redownload... Alternatively, you could download the smaller JP2 and decompress it to a raw binary file. For example, with "kdu_expand" by Kakadu Software (http://www.kakadusoftware.com/index.php).

netcdf : http://www.unidata.ucar.edu/software/netcdf/ ; libraries allow such files to be used in various programs/platforms

this is a stereographic projection, so the sphere was projected onto a plane. This particular grid you mention extends to +/- 1440km in both directions. The projection of a point at 45degS from the south pole is ~1440km away from the pole, hence the name. Such points are at the center of each side. However, when you are at a corner of the grid, at a distance of 1440*sqrt(2)~2037km, you are actually at 29.25degS. The 45deg latitude circle would be a circle that is nearly tangent to the top-center, right-center, bottom-center and left-center point.
(it's like http://www.colorado.edu/geography/gcraft/n.../mapproj_f.html, but we're putting out a square grid instead of a disc).

Erwan

Correct. Polar maps are in stereographic projection (true scale at the pole, R=1737.4km).


The GRD are netcdf-binaries, created with the GMT package (gmt.soest.hawaii.edu). They are double-precision, unlike the IMG and JP2 which are downconverted to 16bit. GMT can convert those to binary 3-column (with grd2xyz), but any netcdf-reader will do.


With more orbits, the gaps between tracks will be reduced (density of detail), but the file sizes should not change.
If your computer can handle those, it will be fine with the future releases


Erwan

Nice rendering
Yes, orbit improvement is ongoing... Hopefully next release some of those orbital track artifacts will be gone!

Rick,
glad the JP2s are working for you (they are all unsigned INT16). But the IMGs are there as well, just in case!

The LOLA data are now also available !
In addition to the RDR and GDR products, I would like to point you to some products which were made with users like you in mind!

First, the big binary GDR files (maps) were converted to GeoJPEG2000, much easier to import in software like ArcGIS. Projection information is included in the headers, so that should work transparently.
location: http://imbrium.mit.edu/DATA/LOLA_GDR/

Second, we are releasing ready-made textures for Celestia. Many of you know Celestia (shatters.net/celestia), and some of you produced normal maps from the Kaguya altimetry data. In addition to a LOLA normal map, a texture showing the topography in false-color was made.
location: http://imbrium.mit.edu/EXTRAS/CELESTIA/

Enjoy !

Erwan
for the LOLA Science Team

This morning, the LOLA instrument was turned on (not the lasers, just the receptors), and began collecting Laser Ranging data later in the afternoon !
Those data are not exactly like SLR (Satellite Laser Ranging), because it is not a two-way link, but they are timetagged at both the transmitting end (the Goddard station) and the receiving end (the LOLA receptor #1, through a fiber optics between a small telescope attached to the Earth-pointing high-gain antenna and the Moon-pointing LOLA instrument). They give an absolute range betwen the Earth and LRO (after some careful correlation and calibration), which will help improve the position knowledge of the spacecraft and benefit all the instruments (especially LROC, which turned on today for a bit!)

(see the LRO blog)

the positions of Luna 17 and 21 (or rather, their Lunokhod rovers) are fairly well known, from Lunar Laser Ranging (mostly used to monitor the position of the Apollo retro-reflectors). I think Luna 21 is the least constrained of the two.

Hello guys,
thought I would register now that LRO has launched successfully

Another cool video is on ULA's website (http://www.ulalaunch.com/)
direct link: http://www.ulalaunch.com/launch/LRO/LROLCR...hHighlights.wmv

I was lucky enough to be invited to the launch, and see it!
One of the pictures I took :

By the way, LRO has a blog with many updates about how it's doing and what's next:
http://lroupdate.blogspot.com/