Triton Voyager 2 Global Color Orthomosaic 600m v1
Product Information:
Voyager 2 data was used to construct the best-ever global color map of Triton. This map has a resolution of 1,970 feet (600 meters per pixel [m]). Color was synthesized by combining high-resolution images taken through orange, violet, and ultraviolet filters; these images were displayed as red, green, and blue images and combined to create this color version (Smith et al., 1989).
Two levels of digital image processing are commonly used for planetary mapping. Digital image processing of the Voyager pictures was done in the Flagstaff Image Processing Facility. The programs and techniques that were used have been developed over a period of several years by a team of scientists and programmers (Batson, 1984). Two levels of digital image processing are commonly used for planetary mapping. Level 1 is intended to restore the pictures to the quality that would have been produced by a “perfect” camera, this is done by removing “artifacts” from lens distortions and electronic recording and transmitting systems. Level 2 processing is done to correct image geometry to match appropriate map projections. Final map/ mosaic complications are done with level 2, geometrically corrected, images (Batson, 1984). Both level 1 and level 2 processing are done to preserve the original contrast captured by the camera which may include very dark and or very light areas. Due to the combination of very low light levels and low albedo of Neptunian rings and satellites, the image sequences required longer exposures times which in turn required specialized sequence design to compensate for image smear caused by spacecraft motion.
Originally released in the PDS Photojournal as file PIA00317 (NASA JPL, 1998).
Mission and Instrument Information:
Triton was discovered in 1846 by Lassel, immediately following the discovery of Neptune. Many of Triton's fundamental properties were unknown prior to Voyager’s encounter due to its proximity to Neptune and low relative brightness which made it difficult to observe Triton from Earth. Improvements such as enlarging tracking antennas of the Deep Space Network (DSN) had to be made to the Voyager system prior to it’s encounter with the Neptunian system to enable data transmission to Earth-based receivers from deep space. Voyager 2 launched on August 20, 1977 onboard a Titan III E-Centaur rocket, it reached the Neptunian system on August 25, 1989.
Triton is by far the largest satellite of Neptune, with a radius of 1,350 (839 mi); about 22% smaller than Earth's moon. It is one of only three objects in the Solar System known to have a nitrogen-dominated atmosphere (the others are Earth and Saturn's giant moon, Titan). Triton has the coldest surface known anywhere in the Solar System (38 K, about -391 degrees Fahrenheit). It is so cold that most of Triton's nitrogen is condensed as frost, making it the only satellite in the Solar System known to have a surface made mainly of nitrogen ice (Stone & Miner, 1989). The pinkish deposits constitute a vast south polar cap believed to contain methane ice, which would have reacted under sunlight to form pink or red compounds. The dark streaks overlying these pink ices are believed to be an icy and perhaps carbonaceous dust deposited from huge geyser-like plumes, some of which were found to be active during the Voyager 2 flyby. The bluish-green band visible in this image extends all the way around Triton near the equator; it may consist of relatively fresh nitrogen frost deposits. The greenish areas include what is called the cantaloupe terrain, whose origin is unknown, and a set of "cryovolcanic" landscapes apparently produced by icy-cold liquids (now frozen) erupted from Triton's interior.
References:
Abelson, P. H. (1989). Voyager 2 at Neptune and Triton. Science, 246(4936), 1369. https://doi.org/10.1126/science.246.4936.1369
Batson, R. (1984). Voyager 1 and 2 Atlas of Six Saturnian Satellites (NASA-SP-474). Washington, DC: National Aeronautics and Space Administration (NASA). https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19840027171.pdf
Greely, R., & Batson, R. (2007). Planetary Mapping. (ISBN 0-521-30774-0). New York, NY: Cambridge University Press.
National Aeronautics and Space Agency (NASA) Jet Propulsion Laboratory (JPL) (2014). Photojournal: PIA18668: Map of Triton. https://photojournal.jpl.nasa.gov/catalog/PIA18668
Smith, B. A., Soderblom, L. A., Banfield, D., Barnet, C., Basilevsky, A. T., Beebe, R. F., Bollinger, K., et al. (1989). Voyager 2 at Neptune: Imaging science results. Science, 246(4936), 1422-1449. https://doi.org/10.1126/science.246.4936.1422
Stone, E. C., & Miner, E. D. (1989). The Voyager 2 encounter with the Neptunian System. Science, 246(4936), 1417-1421. https://doi.org/10.1126/science.246.4936.1417
- Publisher
- USGS Astrogeology Science Center
- Publication Date
- 4 June 1998
- Author
- USGS Astrogeology Science Center
- Originator
- NASA, Jet Propulsion Laboratory, Tammy Becker
- Group
- PDS
- Added to Astropedia
- 13 May 2016
- Modified
- 4 February 2020
General
- Geospatial Data Presentation Form
- Remote-sensing Data, Regional Mosaic
- Edition
- 1998-06-04
- Online Linkage
- https://planetarymaps.usgs.gov/mosaic/Triton_Voyager2_Orthographic_RGB_Mosaic_600m.tif
- Native Data Set Environment
- ISIS v3
- Supplemental Information
- http://photojournal.jpl.nasa.gov/catalog/PIA00317, https://pds-rings.seti.org/neptune/, https://www.sciencedirect.com/topics/earth-and-planetary-sciences/triton, https://www.isprs.org/proceedings/XXXVII/congress/4_pdf/172.pdf, https://www.lpi.usra.edu/resources/outerp/trit.html
Keywords
- System
- Neptune
- Target
- Triton
- Theme
- Flyby missions, Image Processing, Remote Sensing
- Mission
- Voyager
- Mission Specific
- Voyager 2
- Instrument
- ISS
- Search Terms
- Triton, Neptune, Mosaic
Contact and Distribution
- Access Constraints
- None
- Use Constraints
- Public domain
Data Status and Quality
- Currentness Reference
- Publication date
- Progress
- Complete
- Update Frequency
- As needed
- Completeness Report
This only about 1/3 or less of Triton covered in the mosaic.
- Process Date
- 4 June 1998
Lineage
- PDS Status
- PDS 3 Like
- Source PDS Archive
- Voyager
- Source Originator
- Planetary Data Systems (PDS)
- Source Publication Date
- 4 June 1998
- Source Title
- Voyager EDRs
- Source Online Linkage
- http://pds-imaging.jpl.nasa.gov/volumes/voyager.html, https://pds-imaging.jpl.nasa.gov/portal/voyager_mission.html
- Type of Source Media
- Online
Geospatial Information
- Minimum Latitude
- -90
- Maximum Latitude
- 90
- Minimum Longitude
- -180
- Maximum Longitude
- 180
- Direct Spatial Reference Method
- Raster
- Object Type
- Pixel
- Lines (pixels)
- 3500
- Samples (pixels)
- 4500
- Bit Type
- 8
- Quad Name
- Radius A
- 1350000
- Radius C
- 1350000
- Bands
- 3
- Pixel Resolution (meters/pixel)
- 600
- Scale (pixels/degree)
- 39.2699066
- Horizontal Coordinate System Units
- Meters
- Map Projection Name
- Orthographic
- Latitude Type
- Planetocentric
- Longitude Direction
- Positive East
- Longitude Domain
- -180 to 180