LRO LOLA and Kaguya Terrain Camera DEM Merge 60N60S 512ppd (59m)
The LOLA and Kaguya Teams have created an improved lunar digital elevation model (DEM) covering latitudes within ±60°, at a horizontal resolution of 512 pixels per degree (∼59 m at the equator) and a typical vertical accuracy ∼3 to 4 m. This DEM is constructed from ∼4.5×109 geodetically-accurate topographic heights from the Lunar Orbiter Laser Altimeter (LOLA) onboard the Lunar Reconnaissance Orbiter, to which we co-registered 43,200 stereo-derived DEMs (each 1°×1°) from the SELENE Terrain Camera (TC) (∼1010 pixels total). After co-registration, approximately 90% of the TC DEMs show root-mean-square vertical residuals with the LOLA data of <5 m compared to ∼50% prior to co-registration. We use the co-registered TC data to estimate and correct orbital and pointing geolocation errors from the LOLA altimetric profiles (typically amounting to <10 m horizontally and <1 m vertically). By combining both co-registered datasets, we obtain a near-global DEM with high geodetic accuracy, and without the need for surface interpolation. We evaluate the resulting LOLA + TC merged DEM (designated as “SLDEM2015”) with particular attention to quantifying seams and crossover errors. Map values are referred to a radius of 1737400 m.
SELENE is a Japanese mission developed and operated by JAXA. Please credit NASA's LOLA Team and JAXA's SELENE/Kaguya Team.
Reference: Barker, M.K., E. Mazarico, G.A. Neumann, M.T. Zuberc, J. Haruyama, D.E. Smith, (2016), A new lunar digital elevation model from the Lunar Orbiter Laser Altimeter and SELENE Terrain Camera, Icarus, Volume 273, Pages 346–355 doi:10.1016/j.icarus.2015.07.039.
- Publisher
- Goddard Space Flight Center
- Publication Date
- 4 February 2015
- Author
- LOLA Team and Kaguya Team
- Originator
- Group
- PDS
- Added to Astropedia
- 8 September 2015
- Modified
- 4 March 2018
General
- Purpose
This product was produced to generate a high-resolution global topographic model and geodetic framework that enables precise targeting, safe landing, and surface mobility to carry out exploratory activities. It can characterize the polar illumination environment, and images permanently shadowed polar regions of the Moon to identify possible locations of surface ice crystals in shadowed polar craters.
- Geospatial Data Presentation Form
- Topographic Map, Remote-sensing Data, Digital Elevation Model
- SLDEM
- Feburary 4, 2015
- Online Linkage
- https://planetarymaps.usgs.gov/mosaic/LolaKaguya_Topo/Lunar_LRO_LrocKaguya_DEMmerge_60N60S_512ppd.tif
- Native Data Set Environment
- ISIS v3, GDAL
- Supplemental Information
- http://dx.doi.org/10.1016/j.icarus.2015.07.039, http://pds-geosciences.wustl.edu/lro/lro-l-lola-3-rdr-v1/lrolol_1xxx/data/sldem2015/
Keywords
- System
- Earth
- Target
- Moon
- Theme
- Topography, Photogrammetry, Remote Sensing
- Mission
- Lunar Reconnaissance Orbiter, Kaguya
- Mission Specific
- Terrain Camera Stereo
- Instrument
- LOLA, TC
- Search Terms
- SLDEM, DEM, DTM, LOLA, Kakuya, Selene, JAXA
Contact and Distribution
- Access Constraints
- public domain
- Use Constraints
- Please cite authors
Data Status and Quality
- Currentness Reference
- Publication date
- Progress
- Complete
- Update Frequency
- As needed
- Logical Consistency Report
- To reduce the presence of the largest seams, the team replaced the most poorly fit ∼1% of tiles with the original LOLA-only DEMs with interpolation to fill gaps.
- Completeness Report
Only available from -60 to 60 degrees in latitude
- Process Date
- 4 February 2015
- Process Description
Errors in the TC tiles result from imperfect knowledge of the Kaguya orbit, as well as errors in camera pointing, focal length, flat-field, distortion, and jitter. Offsets in the LOLA profiles are due largely to orbit uncertainties and errors in the laser boresight model. To isolate these error sources, the authors followed a two-step approach when co-registering the TC tiles to the LOLA data. In step (1), they derived a 5-parameter coordinate transformation between every TC tile and the full resolution LOLA data in that tile (unbinned point cloud with ∼100, 000 points). Given the large number of individual profiles (typically ∼70 per tile), they expected the LRO/LOLA orbital and pointing errors to average out to very nearly zero in any given tile given they are uncorrelated over the ∼4 years of acquisition. Thus, the tile-averaged transformation parameters compensate predominantly for the Kaguya/TC orbital, pointing, and camera model errors. In step (2), they fit a 3-dimensional (3D) offset to each LOLA profile segment in the transformed TC tile. These offsets reflect primarily the LOLA geolocation errors described above with a secondary contribution from Kaguya/TC errors not completely removed by the transformation in step (1) due to the low number of degrees of freedom.
- Horizontal Positional Accuracy Value
- 10
- Horizontal Positional Accuracy Report
- Accurate to Control Net
- Vertical Positional Accuracy Value
- 4
- Vertical Positional Accuracy Report
- Accurate to Control Net
- Entity and Attribute Overview
- elevation in meters
- Entity and Attribute Detailed Description
- Conversion to local height (meters) is accomplished via the following equation:
Height = (Pixel Value * Scaling Factor)
Conversion to local Radius (meters) is computed as follows:
Radius = (Pixel Value * Scaling factor) + 1737400
where Scaling Factor = 0.5 (as listed in the label as Multiplier)
e.g. conversion using GDAL tools: >gdal_translate -unscale -ot float23 -co bigtiff=if_safer in.cub out_32bit.cub
Elevations were originally computed by subtracting the lunar reference radius of 1737400.0 m from the surface radius measurements. Thus elevation values are the distance above or below the reference sphere.
Lineage
- Source Originator
- Planetary Data System
- Source Publication Date
- 4 February 2015
- Source Title
- SLDEM2015: a merged LOLA Kaguya Lunar DEM
- Source Online Linkage
- http://pds-geosciences.wustl.edu/lro/lro-l-lola-3-rdr-v1/lrolol_1xxx/data/sldem2015/
- Type of Source Media
- Online
- Attribute Accuracy Report
- Accurate to Control Net
Geospatial Information
- Location Description
- Moon
- Minimum Latitude
- -60
- Maximum Latitude
- 60
- Minimum Longitude
- -180
- Maximum Longitude
- 180
- Direct Spatial Reference Method
- Raster
- Object Type
- Pixel
- Lines (pixels)
- 61440
- Samples (pixels)
- 184320
- Bit Type
- 16
- Quad Name
- Radius A
- 1737400
- Radius C
- 1737400
- Control Net
- LOLA
- Bands
- 1
- Pixel Resolution (meters/pixel)
- 59.2252938
- Scale (pixels/degree)
- 512
- Horizontal Coordinate System Units
- Meters
- Map Projection Name
- Equirectangular
- Latitude Type
- Planetocentric
- Longitude Direction
- Positive East
- Longitude Domain
- -180 to 180