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First public release of Kaguya data
Phil Stooke
post Nov 24 2009, 01:13 AM
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Right - no GPS and essentially no geodetic control (3 points, not counting Lunokhod 2 since we don't know its location very precisely in the landscape, maybe only to 100 m or thereabouts). Note that LOLA is dealing with this as much as possible using ground-based laser ranging to LRO.

Phil


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Jim Mosher
post Nov 24 2009, 03:32 AM
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Michael,

The points you listed are all DEM artifacts -- not real lunar features -- with the exception of the one at "32 26 S, 58 57 E" which is possibly a typo. Unless I am continuing to suffer from my coordinate-conversion handicap, I can find no anomaly in the global DEM at 58.95°E/32.43°S...

On the other hand, there are many digital blips not in your list (as well as real lunar features that are missing from the DEM, presumably due to a lack of laser hits). Many of the bad points stand out so much they can be spotted simply by roaming over the raw DEM in grayscale rendition. For example, in Mare Serenitatis, at 16.60°E/21.38°N, there are a couple of bad points with 4-5 km of upward relief (rendered as a fictitious crater just west of Bessel in your maps) that are definitely not present on the Moon (see the attachments for the bad points in the grayscale DEM and the false shadow it generates in the LTVT simulation for tonight's Moon).

Despite its occasional defects, the key point, I think, is that Kaguya's global LALT DEM looks remarkably accurate, overall.

Regarding "the mean error in elevation measurements for Kaguya timing data" the following is the official statement (and explanation, rather opaque to me) in the article "Lunar Global Shape from Kaguya-LALT Laser Altimetry" by H. Araki, et al. Science 323, 897 (2009) by Araki et al. Others better qualified than I can evaluate if they are saying the Kaguya surface positions and elevations are semi-independent of earlier lunar control work. If so, then the agreement of positions, at least, with ULCN2005 is impressive.

-- Jim

QUOTE
Text:

Topography data were produced by incorporating precise orbits for the Kaguya main orbiter. These orbits are calculated from twoway Doppler data by the GEODYN-II software using the latest lunar gravity model SGM90em (SELENE Gravity Model) that is an adapted version of the model SGM90d for the purpose of orbit determination (10–12). Orbit precision is determined from orbit differences during overlapping parts, showing that the radial orbit error is generally within 1 m (13) and the total positioning error (computed using the root sum square over the radial, along-track, and crosstrack directions) is found to be ~50 m. Thus, the radial topographic error originated from the orbit repeatability is 1 m (1 SD), the instrumental error is 0.55 m (1 SD), and the instrument range shift is between +2.5 m and +12 m (8, 9), which are summarized +/-4.1 m (1 SD) as the final budget where the range shift is incorporated as 4 m (1 SD). In the same way, the horizontal topographic error originated from the orbit repeatability is 50 m (1 SD), the pointing error is 175 m (maximum), and the time-tag error is 1.5 m (maximum), which are summarized as +/-77 m (1 SD) as the final budget (14).

References and Notes:

8. H. Araki et al., Adv. Space Res. 42, 317 (2008).

9. One remaining concern is about systematic errors in measurements of pulse arrivals due to distortion of the return pulse caused by the sloped and/or rough target terrain in combination with unknown albedo effects. This error (range shift) may result in underestimates of ranges by 12 m in the very worst case of 30° slope and 30% surface reflectance before the pulse spreading correction. For moderately flat surfaces, systematic range errors are expected to be 2.5 m (8).

10. D. E. Pavlis et al., “GEODYN II system description, vols. 1-5,” Contractor Report, SGT Inc. (2006).

11. J. J. McCarthy, “SOLVE program user's guide,” Contractor Report between NASA/GSFC and Hughes/STX (2007).

12. N. Namiki et al., Science 323, 900 (2009).

13. Orbits are determined by full-scale precision force and measurement modeling. For each data arc, estimated parameters include the state vector at epoch, a solar radiation pressure coefficient, empirical accelerations with a once per orbital revolution signature in the along-track and cross-track direction, and measurement biases to absorb systematic effects and mismodeling. Orbit precision has been evaluated by computing orbit overlap differences. Overlap analysis showed a radial consistency of 1 m in general, with outliers (that were excluded from topography data processing) up to 4 m.

14. The pointing error is considered to be <0.1° (175 m for 100-km altitude), based on the thermal and other deformation analysis of the main orbiter. Time-tag error is <1 msec (1.5 m along-track for 100-km altitude) through the correction that takes into account the propagation time from the main orbiter to each station and the processing delay on each tracking station. These values (175 m and 1.5 m) are incorporated into the final budget as 3 SD errors.

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JohnVV
post Nov 24 2009, 05:41 AM
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as i have been cleaning up the topo data for use in celestia ,those "bad data points" are being removed along with the vertical
stripes as seen here
orig.
[attachment=19800:Screenshot.jpg]
cleaned up
[attachment=19801:Screenshot_1.jpg]

but there IS A miss-alignment with the Clem_NIR_V0.1 data
see my post at shatters.net
http://www.shatters.net/forum/viewtopic.php?f=5&t=15533
for more on that ( i don't like reposting the same thing in different places )
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mhoward
post Feb 16 2010, 06:47 AM
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I just noticed that LALT_LGT_TS files contain 'raw' elevation data by latitude & longitude - and some other data I don't understand yet. Has anyone tried to get a better-resolution elevation map out of them?

Edit: Never mind, I see I missed a post a few back. This has already been mentioned.
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ValterVB
post Feb 28 2010, 05:16 PM
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Here you can find my little experiment with Kaguya data.
Video

The file is DTMTCO_02_00823N200E0310SC
Image center coordinate:
Latitude: 19.95
Longitude: 30.36
Is near Apollo 17 landing site. The red line is the approximate location.
Compare with http://www.lpi.usra.edu/publications/slide...g/slide_35.html

Dimension: 47.748 Km x 42.715 Km
Resolution: 74.036 m (389116 point)
Texture dimension: 6728x5777 px

Illumination conditon: Morning

3D and animation with Blender

Ciao
VB
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Phil Stooke
post Mar 1 2010, 01:22 AM
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People,

Phil here reporting from Houston. I'm at LPSC. At the reception this evening I heard that a utility for opening Kaguya images will be made available in a few months... will say more when I can.

Phil


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ValterVB
post Mar 29 2010, 08:55 PM
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Here you can find a script for import LALT_GGT_NUM dataset from the JAXA in Blender. The name of the file to download is Moon importer.blend
You can choice latidude and longitude and then the script import the date.

All you need is Blender (not version 2.5) and the file LALT_GGT_MAP.IMG. Before to run the script change the path on the script (on the top/left of the windows
This is an example. (Pay attention to the number of vertices, my max limit is 2 millions of vertices)



If you speak italian you can see my blog, where I explain How to do

Ciao
VB
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Nirgal
post Sep 13 2010, 09:54 AM
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I have only very recently discovered the treasure trove of KAGUYA data and have a question specifically to the TC (Terrain Camera) Data that I have not been able to answer from reading through all of the KAGUYA thread so dar.
It seems that others (Phil Stooke) already did quite some work with the TC data so maybe they could help answer the following question: So is it really true that there is already global (or a substantial fraction of global) coverage of TC derived DEM data as suggested by the official KAGUYA mission statements (which would be really, really ueber-awseome: a global DEM at 10 meter resolution, i.e. about 100 times (!) more detailed than the laser altimeter derived maps at about 1 kilometer per pixel). It also seems that Google Moon is already using a high resolution DEM in many places which from the look at it seems more detailed than the usual 1-kilometer per pixel altimeter DEM (but not as detailed than a 10-meter DEM ? (anyone know what datasets are exactly used by Google Moon ?)

What I have been able so far ist to download and process TC DEMs for selected areas but I have trouble to fnd the proposed "global coverage".
When looking at the TC overlays in 3D Moon Java App there seem to appear also only very few areas.
So is this still unreleased material or am I doing the wrong search ?
Interestingly, when doing a "blank" search at the Kaguya data archive for all TC DEMs it returns around 30.000 records which looks promising for near global coverage but I have not been able to do a more targeted GIS-style or at least coordinate based search which returns only sparse coverage in selected areas.

Thanks a lot for any suggestions !
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Phil Stooke
post Sep 13 2010, 01:55 PM
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Sorry folks - I did look at this stuff when it first became available, briefly, but I don't find the access very convenient, and I never found access to more than a very restricted subset of images (and never tried the altimetry). I'm tied up with Mars and asteroids at the moment and not doing much with the Moon. Note to people planning online access to data - keep it as simple as possible!

Phil


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... because the Solar System ain't gonna map itself.

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Nirgal
post Sep 14 2010, 09:44 AM
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QUOTE (Phil Stooke @ Sep 13 2010, 03:55 PM) *
I'm tied up with Mars and asteroids at the moment and not doing much with the Moon. Note to people planning online access to data - keep it as simple as possible!

Phil


nevermind Phil ! thanks for the answer anyway.
Your reporting similar troubles with the dataset basically already answers my main question: so it's not just me having trouble with the access details of the TC Kaguya dataset.
I thought it might be something simple like just using the wrong front end or that a large part of the TC data might still be unreleased for the higher processing levels... something like that...
So I will try to take more time to grind myself further trough this... I will keep you all updated when I find out anything useful.

B.
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Nirgal
post Sep 16 2010, 03:45 PM
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ok, after some further research I found the following interesting information directly from the JAXA Kaguya-Team posted at the Telescope Review forum which directly addresses my question about coverage and release schedule of the Terrain Camera derived DEMs. As I already suspected, the bulk of the data seems to be still in processing. The interview sounds very promising although we will probably have to wait another year or so for the availability of full global coverage.

QUOTE
I asked Shin-ichi Sobue of the JAXA Kaguya –team the following questions. Here is the e-mail correspondence (released with permission):

“Q: Is the additional data set to be released on November the 1st 2009? What will it contain?

A: We will provide all available standard products from Kaguya mission instruments which is shown in here.

Q: The Kaguya Laser Altimeter Data (in resolution of 1 data point per 1 degree) has been kindly reseased on February 2009. Is the data produced by Terrain Mapping Camera (the full topographic data set) going to be released? How well is the Lunar surface covered with that data?

A: Terrain Camera (Not TMC, TMC is Indian) observed more than 90% surface of the Moon with 10 meter resolution. But, it takes additional 1-2 years to provide global DTM by TC. On the other hand, about LALT, we will provide 1/16 degree topographical map on November.”


BTW.: can't wait for the Indian TMC DEMs which are announced to be even more detailed at 5 meters per pixel vs. 10 m/pixel for the Kaguya TC.
(However I would suppose that the 10 and 5 meter resolution does apply to the orthoimages only, not for the DEMs themselves because the process of photogrammetry (stereo derived DEM construction) usually needs a small window of 3x3 to 5x5 pixels for each DEM height value. That's why, for example the HiRISE Mars DTMs have a 1 meter/pixel resolution while the images they are derived from come with 0.25 m/pixel.
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JohnVV
post Sep 21 2010, 08:32 AM
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i have to agree with phil the KAGUYA site was never very user friendly .Usable yes, but very limited for us amateurs / enthusiasts
the dem released was very quickly surpassed by the LOLA data .

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