Robin Fergason
Donna Galuszka
Trent Hare
David Mayer
Bonnie Redding
Ethan Smith
20200724
Context Camera Digital Terrain Model; J21_052811_1983_XN_18N282W, J22_053233_1984_XN_18N282W
raster digital data
https://doi.org/10.5066/P906QQT8
Mars 2020 Terrain Relative Navigation
20200724
DTM_MOLAtopography_DeltaGeoid_20m_Jezero_J21_J22X_v7pt1_Eqc_latTs0_lon0.tif
raster digital data
Flagstaff, Arizona
United States Geological Survey, Astrogeology Science Center
http://astrogeology.usgs.gov
This is a digital terrain model (DTM) extracted from Context Camera (CTX) stereo images from the Mars Reconnaissance Orbiter mission. The original data product is a DTM from stereo images acquired at approximately 6 meters/pixel resolution, which allows an output DTM resolution of 20 meters/pixel using a softcopy photogrammetry system. The CTX images used were further processed from those in the Planetary Data System to remove any remaining focal and lens distortion, to dejitter the images, and to correct timing information. These processing steps were developed in collaboration with the Jet Propulsion Laboratory and image processing script version 7.1 was used. Because careful corrections were made to the intrinsic and extrinsic properties of the images, no bundle adjustment was performed when generating the DTM. The DTM was simply extracted from the processed stereo pair images. The DTM was registered horizontally and vertically in local north, east, down coordinates using a rigid 3D translation to a High-Resolution Stereo Camera (HRSC) DT5 DTM provided for the Mars 2020 mission by the German Aerospace Center (DLR) and the HRSC team. Elevation values are in meters and refer to the Mars 2020 IAU Sphere with a radius of 3396190m.
The Mars 2020 rover will explore Jezero crater, Mars to investigate an ancient delta for evidence of past microbial life and to better understand the geologic history of the region. In support of Terrain Relative Navigation (TRN), the USGS Astrogeology Science Center has generated and delivered the Lander Vision System (LVS) map generated from three Context Camera (CTX) orthorectified images that will be onboard the spacecraft and will be considered the truth dataset that TRN will use to orient itself relative to the surface during Entry, Decent, and Landing. The purpose of this work was to generate and deliver Context Camera (CTX) digital terrain models (DTMs) used to generate the orthorectified images used in the Lander Vision System (LVS) map. This DTM serves as a foundation for ortho-projection and control of the LVS map orthoimages and mosaics.
20190820
Publication date
None
77.0241
77.6129
18.6506
17.8904
Planetary
Mars 2020
Terrain Relative Navigation
Entry, Decent, and Landing (EDL)
Context Camera
Mars Reconnaissance Orbiter
Digital Terrain Model (DTM)
Mars
http://science.nasa.gov/glossary
Mars
None
None
Robin L Fergason
U.S. Geological Survey, Southwest Region
Supervisory Physical Scientist
mailing address
2255 North Gemini Drive
Flagstaff
AZ
86001
US
928-556-7034
928-556-7014
rfergason@usgs.gov
Mars Reconnaissance Orbiter Context Camera
None
Unclassified
None
ISIS 3.5.2, GDAL 2.3.1, SOCET SET 5.6, Ames Stereo Pipeline 3.6.0, ArcMap 10.6
See Process Steps.
See Process Steps.
The Context Camera (CTX) stero images used to generate this DTM are J21_052811_1983_XN_18N282W.pgm and J22_053233_1984_XN_18N282W.pgm.
To assess the horizontal registration, measurements between orthorectified images were made using the Open Source software package IMCORR (https://nsidc.org/data/velmap/imcorr.html). The approach used by IMCORR is the same basic matching strategy used in a variety of stereo photogrammetry software packages, and when applied to a pair of orthorectified images, the results can be interpreted as a measure of the co-registration of the images.
36.5
The CTX orthoimage is horizontally displaced from the HRSC L5 orthoimage reference by a median magnitude of 36.5 meters preferentially oriented to the southeast. 94% of the matched points are displaced by less than 60 meters from the HRSC reference and are within stated TRN requirements.
To assess the vertical differences, DTMs were simply differenced.
3.8
The vertical registration between individual CTX DTMs is 3.8 meters after adjusting the mosaic by 183.3 meters vertically to align with HRSC. This value is within the theoretical maximum vertical precision of the HRSC DTM (~13 meters) and is within the stated TRN requirements of measured vertical offsets of less than 20 meters.
Malin, M.C. et al.
Malin, M.C. et al., Context Camera Investigation on board the Mars Reconnaissance Orbiter, J. Geophys. Res. 112, E05S04 (2007). doi:10.1029/2006JE002808
2007
Context Camera Investigation on board the Mars Reconnaissance Orbiter
document
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2006JE002808%4010.1002/%28ISSN%292169-9100.MARSROM1
Planetary Data System (PDS) Reduced Data Record (RDR)
2006
2020
ground condition
CTX visible
https://pds-imaging.jpl.nasa.gov/volumes/mro.html
To achieve the required horizontal and vertical co-registration requirements, we have developed a DTM mosaic generation pipeline using a combination of SOCET SET from BAE Systems and the Ames Stereo Pipeline (ASP) software. The original data product is a DTM from stereo images acquired at approximately 6 meters/pixel resolution, which allows an output DTM resolution of 20 meters/pixel using a softcopy photogrammetry system. The CTX images used were further processed from those in the Planetary Data System to remove any remaining focal and lens distortion, to dejitter the images, and to correct timing information. These processing steps were developed in collaboration with the Jet Propulsion Laboratory (JPL) and image processing script version 7.1 was used. These modifications have significantly improved the positional knowledge of the images relative to the martian surface and have allowed us to generate DTMs without the need for a typically required bundle adjustment. Omitting this step was desirable, as TRN is sensitive to non-linear distortions that could potentially be introduced by a bundle adjustment.
After DTMs were produced using SOCET SET from input images and image metadata provided by JPL, the initial DTMs were then rigidly aligned to one another using the pc_align program from Ames Stereo Pipeline (ASP), allowing only a translation adjustment. The relatively-aligned DTMs were then simultaneously aligned using ASP to the High Resolution Stereo Camera (HRSC) Level 5 DTM provided for the Mars 2020 mission by the German Aerospace Center (DLR) and the HRSC team to bring them into absolute alignment with an independent reference. CTX DTMs were exported at 20 meters per pixel. Elevation values are in meters and refer to the Mars 2020 IAU Sphere with a radius of 3396190m.
20190820
Robin L Fergason
U.S. Geological Survey, Southwest Region
Supervisory Physical Scientist
mailing address
2255 North Gemini Drive
Flagstaff
AZ
86001
US
928-556-7034
928-556-7014
rfergason@usgs.gov
Raster
Grid Cell
2253
1745
1
Equirectangular
0.0
0.0
0.0
0.0
row and column
20.0
20.0
meters
D_Mars_2000_Sphere
Mars_2000_Sphere_IAU
3396190.0
1.0E-10
DTM_MOLAtopography_DeltaGeoid_20m_Jezero_J21_J22X_v7pt1_Eqc_latTs0_lon0.tif
Raster geospatial data file.
Producer Defined
Value
Unique numeric values contained in each raster cell.
Producer Defined
-2656.39453125
-1546.488525390625
Trent M Hare
U.S. Geological Survey, Southwest Region
Cartographer
mailing address
2255 North Gemini Drive
Flagstaff
AZ
86001
US
928-556-7126
thare@usgs.gov
Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Digital Data
https://astrogeology.usgs.gov/search/map/Mars/Mars2020/JEZ_ctx_B_soc_008_DTM_MOLAtopography_DeltaGeoid_20m_Eqc_latTs0_lon0
None
20200630
Robin L Fergason
U.S. Geological Survey, Southwest Region
Supervisory Physical Scientist
mailing address
2255 North Gemini Drive
Flagstaff
AZ
86001
US
928-556-7034
928-556-7014
rfergason@usgs.gov
FGDC Content Standards for Digital Geospatial Metadata
FGDC-STD-001-1998