ODE Features and Feature Layers

ODE uses surface features in both the product and the map search pages. ODE also includes a "Feature Layer" basemap on the map page. The features aid user in finding products that cover specific locations on the body surface. The feature names and locations are drawn from the USGS Gazetteer of Planetary Nomenclature.

Coordinates in the gazetteer database are in the IAU-approved coordinate system for each body as listed below:

IAU-accepted coordinate systems:

Target	Coordinate Systems	Control Networks	Cartographic Reference Ellipsoid
Mars	Planetocentric, +East, 0 - 360 Planetographic, +West, 0 - 360	MDIM 2.1 MDIM 2.0	Ellipsoid, with radii (A: 3396.19 & C: 3376.2) km
Mercury	Planetographic, +West, 0 - 360	Preliminary MESSENGER	Spherical, with radius 2439.7 km
Moon	Planetographic, +East, -180 - 180	ULCN 2005 LOLA 2011	Spherical, with radius 1737.4 km
Venus	Planetocentric, +East, 0 - 360		Spherical, with radius 6051.8 km

• All bodies are cartographically treated as spheres, except Mars, which means there is no difference between a planetocentric and planetographic latitude system.

• The latitude, longitude, and size of each Mars feature were digitally measured in 2001 and 2002 using the Mars Digital Image Mosaic (MDIM) version 2.0. and satellites.

• The Lunar Nomenclature contains the lettered craters on the Moon from NASA Reference Publication 1097, NASA Catalogue of Lunar Nomenclature, by Leif E. Andersson and Ewen A. Whitaker, 1982. Some spellings in the NASA 1097 have been changed to match the IAU-approved spellings of the parent craters.

• The Moon features used in ODE are in the LOLA 2011 control network

• The features on Venus have not been systematically updated like the Moon, Mars, and Mercury features.

ODE's "Feature Layer" basemaps were produced from the USGS Gazetteer shapefiles. The USGS Gazetteer shapefiles were projected to different projections using ArcGIS tools. There are four projections used in ODE feature basemaps: Simple Cylindrical projection centered at 0 longitude; Simple Cylindrical projection centered at 180 longitudes; north polar stereographic projection; and south polar stereographic projection. Maps in the polar stereographic projections are limited to the area from 60N to 90N or 60S to 90S latitudes range. The Mars and Moon features in ODE added some additional features such as the successful Landers. ODE queries supports both point and polygon features. All linear features are adjusted slightly in the value of the extent with ±0.1 degrees to make a polygon coverage. Coordinates of features are updated from time to time by the Planetary Geomatics Group of the USGS Astrogeology Science Center as new control networks and image mosaics become available.

Please see more information on the Planetary Nomenclature website.