PDS_VERSION_ID = PDS3 LABEL_REVISION_NOTE = " CHRIS ISBELL AND LISA GADDIS, 2007-05-01" RECORD_TYPE = STREAM SPACECRAFT_NAME = "CLEMENTINE 1" TARGET_NAME = MOON OBJECT = DATA_SET DATA_SET_ID = "CLEM1-L-N-5-DIM-NIR-V1.0" OBJECT = DATA_SET_INFORMATION DATA_SET_NAME = " CLEMENTINE NIR DIGITAL IMAGE MODEL" DATA_SET_COLLECTION_MEMBER_FLG = "N" START_TIME = 1994-01-25 STOP_TIME = 1994-05-07 DATA_SET_RELEASE_DATE = 2007-05-01 PRODUCER_FULL_NAME = "LISA R. GADDIS" DETAILED_CATALOG_FLAG = "N" DATA_OBJECT_TYPE = "IMAGE" DATA_SET_DESC = " Data Set Overview ================= The Clementine NIR DIM Mosaic is a full-resolution (100 meters per pixel),radiometrically and geometrically controlled, photometrically modeled global mosaic produced by the U.S. Geological Survey from Clementine EDR Data. Imaging data acquired by the Near-Infrared Camera were used to create the multi-band mosaic. The NIR mosaic is mapped in the Sinusoidal Equal-Area Projection and partitioned into 996 quadrangles (quads) or “tiles” equivalent to those of the previously released 750-nm UVVIS basemap (PDS CD volumes CL_3001 through CL_3015) and the UVVIS DEM (PDS CD volumes CL_4001 through CL_4078). This 100 m/pixel version of the NIR DIM is presented on 13 DVD volumes (equivalent to 78 ‘virtual CD’ volumes). Although the tiling scheme is identical to the original basemap, each 30- degree longitudinal section of the basemap now represents one DVD volume (equivalent to 6 virtual CD volumes). For each full resolution image product, subsampled enhanced color and comparative ratio ‘browse’ images are provided in Joint Photographic Experts Group (JPEG) format. Reduced-resolution planet-wide NIR mosaics (e.g., at 0.5, 2.5, and 12.5 km/pixels) will be made available online at the PDS Map-a-Planet Web site (http://pdsmaps.wr.usgs.gov/maps.html) along with the full resolution NIR mosaic. In general, this design consists of rectangular tiles that are roughly 2100 pixels on a side. The actual tile size varies with latitude. Near the equator, each tile covers 7 degrees of latitude and 6 degrees of longitude. A typical full-resolution 6-band tile requires ~58 megabytes of digital storage. Parameters ========== N/A Processing ========== As was the case for the UVVIS mosaic, the U.S. Geological Survey Integrated Software for Imagers and Spectrometers (ISIS) processing system was used to generate the NIR mosaic. Because the final steps of the NIR data processing followed the UVVIS processing by several years, the same version of ISIS (v.2.0, or 'Old ISIS') was frozen in place and used for both datasets. ISIS cartographic processing for the NIR mosaic includes radiometric correction, geometric control to the Clementine 750-nm basemap mosaic, spectral registration, photometric normalization, and image mosaicking to produce near-seamless, uniformly illuminated views of the surface of the Moon at 6 wavelengths. Radiometric correction applies 'flat fielding,' dark current subtraction, non-linearity correction, and conversion to radiometric units (usually radiance). Geometric transformations tie each raw image with the ground control network from the basemap mosaic and convert from raw image coordinates to the Sinusoidal Equal-Area projection. Photometric normalization is applied to balance brightness variations due to illumination differences among the images in a mosaic. The first four NIR bands (1100 to 2000 nm) have also been normalized to reflectance based on the approach previously applied to the calibrated UVVIS global mosaics. Images are then mosaicked together to form a global map of continuous image coverage for the entire planetary body. Media/Format ============ The Clementine NIR mosaic is delivered to the Planetary Data System using DVD media. Formats are based on standards for such products established by the Planetary Data System (PDS) [PDSSR1992]. " CONFIDENCE_LEVEL_NOTE = " Overview ======== Both the Clementine NIR and UVVIS mosaics were geometrically controlled to the previously published 750-nm Clementine Basemap Mosaic (PDS volumes CL_3001 through CL_3015) by tying individual NIR images that make up a color set to the corresponding image used to produce the basemap mosaic. The 750nm basemap mosaic was geometrically controlled using the methods described below. Although shortcomings have since been identified, the 750-nm basemap mosaic significantly improved the geometric control of the Moon from previous maps and ground control points. On the basis of best-effort measurements of the spacecraft orbit and pointing, UVVIS geometric distortions, and time tags for each observation, the Clementine Spacecraft, Planet Instrument, C-matrix, and Event kernels (SPICE) data alone provide positional accuracy better than 1 kilometer over most of the Moon. The geometric processing goal of the basemap was for 95% of the Moon (excluding the oblique observation gap fills) to have better than 0.5 km/pixel absolute positional accuracy and to adjust the camera angles so that all frames match neighboring frames to within an accuracy of 2 pixels. To achieve these goals, camera alignment and pointing data were required to be accurate to a few hundredths of a degree. The absolute alignment of the UVVIS was determined with respect to spacecraft-fixed axes (A and B Star Tracker Camera quaternions) by analyzing a major subset of the over 17,000 images of Vega, over 6,000 images of the Southern Cross, and a few hundred images of the Pleiades, taken during the approach to the Moon and throughout the lunar mapping phase of the Clementine mission. Multiple star images within a single picture were used to determine the UVVIS focal length and optical distortion parameter values. Approximately 265,000 match points were collected at the USGS from ~43,000 UVVIS 750 nm images providing global coverage. Approximately 80% of these points were collected via autonomous procedures, and the remaining 20% were collected manually. Streamlined procedures for the supervised collection of match points were developed and applied, and these procedures saved several person-years of effort. The automated success rate exceeded 90% along each spacecraft orbit track, where the overlap regions of successive images are highly correlated, but failed when the overlap region is narrow and/or nearly featureless. ('Failure' is defined as less than 3 points per image with correlation coefficients greater than 0.85; thus, many good match points were rejected because we could not be certain that the matches were valid without verification.) Across-track matching was more difficult due to changes in scale and illumination angle, but a fair success rate (~60%) was achieved via the use of 'window-shaping' (local geometric reprojections). The oblique gap-fill images were the most difficult to match and required substantial human intervention. Matching the polar regions was time-consuming because each frame overlaps many other frames. Most match point locations were found to a precision of 0.2 pixel. The USGS match points were provided to Tim Colvin and Mert Davies of the RAND Corporation for analytical triangulations. Using these match points, control points from the Apollo region, and the latest SPICE kernels from Navigation and Ancillary Information Facility (NAIF) at JPL, RAND determined improved camera orientation angles for the global set of UVVIS images. A constant lunar radius of 1737.4 kilometers was assumed, and this was later found to be a significant source of error near the oblique gap fills. The analytical triangulation is a least-squares formulation designed to adjust the latitude and longitude of the control points and the camera orientation angles to best fit the match points. The triangulation was first computed on 'packets' of match points (each covering about one-eighth of the Moon), then checked and rechecked at the USGS via plots and test mosaics to fix and add match points as needed. The final (global) analytical triangulation required the solution of ~660,000 normal equations. The mean error is less than 1 pixel. This effort was by far the largest analytical triangulation ever applied to a planetary body other than Earth. The results defined the planimetric geometry of the 750-nm basemap, to which all systematic Clementine mosaic products have been tied." END_OBJECT = DATA_SET_INFORMATION OBJECT = DATA_SET_TARGET TARGET_NAME = MOON END_OBJECT = DATA_SET_TARGET OBJECT = DATA_SET_HOST INSTRUMENT_HOST_ID = CLEM1 INSTRUMENT_ID = UVVIS END_OBJECT = DATA_SET_HOST OBJECT = DATA_SET_REFERENCE_INFORMATION REFERENCE_KEY_ID = "PDSSR1992" END_OBJECT = DATA_SET_REFERENCE_INFORMATION END_OBJECT = DATA_SET END