This page has been created as part of a project to put planetary control networks on the web. This control network for Neptune’s moon, Triton, originated from Merton Davies and Tim Colvin and Frank Katayama at the RAND Corporation, and Peter Thomas from Cornell University, and was provided to the USGS in 2000. The control network solution was originally performed with software developed at RAND, and documented by Colvin (1992). Each control network is essentially a set of photogrammetric solution (input and output) files. The input files consist of, aside from a priori information, measurements of common points (control points, sometimes called tie points) on images of a planetary body. The output files include the body coordinates of the control points in latitude, longitude, and radius, and revised orientation information (camera pointing) for the images. The primary use of such information is for the creation of image mosaics of the planetary body. However, these solutions can also provide fundamental data on the size and shape of the body, its rotation period, and the direction of its polar axis in space. The control point coordinates also usually serve as a coordinate reference frame that defines the fundamental coordinate reference system for the body in question. Formatting of this control network data for Neptune’s moon, Triton, has yet to be updated for compatibility with the USGS ISIS2 and ISIS3 cartography software. The RAND control network available here has 52 points spanning 6 images, and is described in (Davies et al., 1979). This release is comprised of data from original RAND control network solutions from Voyager I and II images.
This global mosaic of Triton utilizes the best image quality and moderate resolution coverage supplied by the Voyager I and II spacecraft. This mosaic was prepared by the RAND Corporation. The image data was selected on the basis of overall image quality, reasonable input resolution and availability of moderate viewing and sun angles for topography.
- USGS Astrogeology Science Center
- Added to Astropedia
- 7 August 2017
- 13 April 2018
Created as part of a project to put planetary geodesy control networks on the web. These control network data were originally provided by Merton Davies and Tim Colvin of the RAND Corporation. Funds were provided for a conversion and archiving effort by the NASA Planetary Geology and Geophysics Program and the NASA Cartography Program.
- Geospatial Data Presentation Form
- Control Network
Contact and Distribution
- Access Instructions
Contained in the ZIP file are the necessary data to open the RAND solution of the Triton control network in its original RAND solution format.
Triton_control_images.zip – All Voyager I & II images in the Triton control network in PDS (.imq) format.
nep_inp.dat – RAND solution “poles, points, and positions” a priori input file.
nep_mea.dat – RAND solution image measurements (mm) input file.
nep_par.dat – RAND solution program operation control input file.
Documentation and Information:
Triton_image_list.txt – Text file listing all Voyager I & II images in the Triton control network. These images are archived at pds.nasa.gov in PDS (.imq) format.
ISIS-PG-FMT501_parXX_dat – Description of format of file nep_par.dat (in PDF format).
ISIS-PG-FMT502_outXX_dat – Description of format of file nep_inp.dat (in PDF format).
ISIS-PG-FMT503_meaXX_dat – Description of format of file nep_mea.dat (in PDF format).
- Quad Name
- Horizontal Coordinate System Units