Phobos Mars Express HRSC Color Shaded Relief 100m

Primary Authors

Mars Express HRSC Instrument Team

Originators

Europlanet Research Infrastructure

Publisher

USGS Astrogeology Science Center

Publication Date

2009-06-01

Abstract

Product Information: This is a colorized shaded-relief of the original High Resolution Stereo Camera (HRSC) Digital Elevation Model (DEM) with a resolution of 100 meters per pixel (m). HRSC images were used to obtain 3-dimensional coordinates of surface points of Phobos and used to derive the DEM. As currently the HRSC could not gain global coverage yet, the data was complimented by Viking orbiter image data to be able to provide the digital terrain model globally (Willner et al., 2010). The research leading to the data products has received funding from the European Community's Seventh Framework Programme ([FP7/2007-2013]) under grant agreement number 263466 for the FP7-ESPaCE program. Mission and Instrument Information: Mars Express is a mission of the European Space Agency (ESA) it launched in June 2003 onboard a Soyuz-Fregat launcher from the Baikonur Cosmodrome in Kazakhstan. There are seven instrument suites onboard Mars Express: Aspera Energetic Neutral Atoms Analyzer (ASPERA), High/Super Resolution Stereo Colour Imager (HRSC, SRC), Mars Radio Science Experiment, Mars Subsurface Sounding Radar/Altimeter (MARSIS), Omega IR Mineralogical Mapping Spectrometer (Omega), Planetary Fourier Spectrometer (PFS), and UV and IR Atmospheric Spectrometer (SPICAM). The instrumentation onboard Mars Express was designed to reach the scientific objectives of the mission which include: global high-resolution photogeology at 10 m per pixel resolution, super resolution photogeology of selected areas of the planet at 2 meters per pixel, global high spatial resolution mineralogical mapping at a resolution range from a kilometer per pixel to several 100 meters per pixel, global atmospheric circulation characterization, subsurface characterization, surface-atmosphere interaction, structure of the interior and surface geochemistry and exobiology. Phobos is a very irregular body often approximated by a tri-axial ellipsoid for simplicity. With a mean distance of only 9375 km to the center of Mars – which relates to approximately 6000 km above the Martian surface – it is orbiting deep in the Martian gravity field. Its orbit is in a nearly equatorial plane and almost circular Reference: Willner, K., Oberst, J., Hussmann, H., Giese, B., Hoffman, H., Matz, K.-D., Roatsch, T., & Duxbury, T. (2010). Phobos control point network, rotation, and shape. Earth and Planetary Science Letters, 294(3–4), 541-546. https://doi.org/10.1016/j.epsl.2009.07.033

Purpose

The German Aerospace Center (DLR) was involved in an in-depth study of Phobos, a natural satellite of Mars. Based on images of the multi-spectral line scanning High Resolution Stereo Camera (HRSC) and the Super Resolution Channel (SRC) – a frame camera – the department of Planetary Geodesy was to observe Phobos in its orbit, determined shape parameters computed global digital elevation models, prepared a first low scale maps based on image data only, derived new estimates on its rotational parameters and could derive mass distribution models agreeing to all other constraining parameters.

Contact and Distribution

Format

Remote-sensing Data, Shaded-Relief Map, Topographic Map

Access Constraints

public domain

Access Scope

PDS

Use Constraints

Please cite authors

Edition

0.1

Supplemental Information

http://www.sciencedirect.com/science/article/pii/S0012821X09004506, https://www.dlr.de/dlr/en/desktopdefault.aspx/tabid-10364/548_read-400/#/gallery/657

Native Data Set Environment

ISIS v3

Astrogeology Theme

Image Processing, Photogrammetry, Remote Sensing, Topography

Mission Names

Mars Express

Instrument Names

HRSC

Online Package Link

https://astrogeology.usgs.gov/search/map/phobos_mars_express_hrsc_color_shaded_relief_100m

External File Size

724 kB

Online File Link

https://planetarymaps.usgs.gov/mosaic/Phobos_ME_HRSC_ClrShade_Global_2ppd.tif

Contact Address

2255 N. Gemini Drive

Contact City

Flagstaff

Contact State

AZ

Contact Postal Code

86001

Contact Email

astroweb@usgs.gov

Data Status and Quality

Time Period of Content (start)

2003-01-01

Time Period of Content (stop)

2009-12-31

Currentness Reference

Ground condition

Progress

In Work

Update Frequency

As needed

Logical Consistency

HRSC images were used to obtain 3-dimensional coordinates of surface points of Phobos (Willner et al., 2010).

Completeness Report

As currently the HRSC could not gain global coverage yet, the data was complimented by Viking orbiter image data to be able to provide the digital terrain model globally. It is anticipated to further improve and update the terrain model, the preliminary image mosaics, and maps with more image data available.

Process Description

All processing was completed using Geospatial Data Abstraction Library (GDAL) tools on the original DEM. GDAL commands were used: > > (1) gdaldem hillshade input_dem output_hillshade -z 2 (ZFactor) -az 315 (Azimuth) -alt 45 (Altitude) > > (2) gdaldem color-relief input_dem color_text_file output_color_relief_map > > (3) hsv_merge.py output_color_relief_map output_hillshade output_color-hillshade. > Pixels do not contain any of the original explicit elevation information. The colorized shaded-relief represents approximate elevations based on the original topographic data. Elevations values are mapped based on the defined red, green, and blue mapping listed next. All NoData values are mapped to 0, 0, 0 (black). Thus 0 percent (purple) maps to minimum elevation and 100 percent (white) maps to maximum using a linear stretch between percentages. > > nv 0 0 0 //No Data > 0% 255 120 255 //purple > 20% 120 120 255 //blue > 40% 120 255 255 //aqua > 60% 120 255 120 //green > 70% 255 255 120 //yellow > 90% 255 120 120 //red > 100% 255 255 255 //white

Lineage

Process Date

2015-11-09

Source Title

Phobos

Source Online Linkage

{https://pds-imaging.jpl.nasa.gov/volumes/mex.html,https://pds-imaging.jpl.nasa.gov/portal/mex_mission.html}

Source PDS Archive

Mars Express

PDS Status

PDS 3 Like

Attribute Accuracy Report

Best Effort

Horizontal Positional Accuracy Report

Best Effort

Geospatial Information

Target

Phobos

System

Mars

Minimum Latitude

-90.15

Maximum Latitude

90

Minimum Longitude

-180.15

Maximum Longitude

180.66

Direct Spatial Reference Method

Raster

Object Type

Grid Cell

Raster Row Count (lines)

349

Raster Column Count (samples)

699

Bit Type (8, 16, 32)

8

Quad Name

Radius A

11100

Radius C

11100

Bands

3

Pixel Resolution (meters/pixel)

100

Scale (pixels/degree)

1.9373

Map Projection Name

Simple Cylindrical

Latitude Type

Planetocentric

Longitude Direction

Positive East

Longitude Domain

-180 to 180