Data Set Information
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| DATA_SET_NAME |
LCROSS EARTH/MOON VISIBLE CAMERA 2 RAW DATA V1.0
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| DATA_SET_ID |
LCROSS-E/L-VIS-2-RAW-V1.0
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| NSSDC_DATA_SET_ID |
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| DATA_SET_TERSE_DESCRIPTION |
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| DATA_SET_DESCRIPTION |
Data Set Overview : This data set contains context imagery from the visible light camera (VIS) on the LCROSS spacecraft. The images in this dataset have targets named Moon, Earth and Calibration (i.e., not targeted). Each raw image file is a 24-bit RGB image, with a 720 x 486 pixel format. The image aspect ratio [H:V] is 1.33. The effective field-of-view [FOV] is 30.5 [H] x 22.8 [V] degrees. The time each image was captured is encoded in the image's filename like this: LCROSS_VIS_RAW_.IMG where : YYYYMMDDHHMMSSmmm and YYYY : the four digit year; MM : the two digit month, DD : the two digit day, and so on through hours, minutes, seconds and milliseconds. Detached labels for each image have the same filename as the image but with the 'LBL' extension. Related Data Sets : There is no dataset containing radiometrically calibrated images from this camera. The field of view of this camera overlaps with the fields of view of all other instruments except Near Infrared Spectrometer #2 (NSP2). Parameters : Science ------- There are no configurable parameters for the visible camera. Housekeeping ------------ Instrument temperature at the image generation time is reported in the label file under: INSTRUMENT_TEMPERATURE, INSTRUMENT_TEMPERATURE_COUNT in degrees Centigrade and raw counts, respectively. This is a single telemetry point most representative of the camera chassis temperature for the image. Processing : The detector produces 768 x 494, RGB images. Each image was converted inside the camera to an analog, NTSC image and transmitted to the spacecraft. The spacecraft multiplexed this camera with the two near-infrared cameras, receiving images from only one of these three cameras at a time. When received, the spacecraft converted each NTSC image to a 720 x 486, 24-bit RGB digital image and compressed it using a lossy, proprietary, wavelet-based compression algorithm for downlink. On the ground, the images are decompressed and recompressed losslessly as RGB PNG files by GSEOS (Ground Support Equipment Operating System). The LCROSS Make Archive program read these files, selected the Red channel, and wrote that as a three-channel, PDS-formatted (.IMG) file and a FITS file. Data : These files are stored as PDS-formatted, three channel, 8-bit MSB_UNSIGNED_INTEGER files. Each image file has a corresponding detached PDS label file sharing the same filename and an 'LBL' filetype. The EXTRAS directory contains these images in FITS format as well. Coordinate System : These images have been left in the camera's coordinate system. These images need to be rotated +233 degrees to place them in the LCROSS Payload Common Camera Coordinate System. A description of mapping the images with respect to each other and the S/C coordinate system is contained within the LCROSS Instrument Response and Calibration Report. Software : The GSEOS Version used to generate these images is GSEOS 5.2.407 (Feb 25, 2008), Python 2.2.3 (#37, Nov 28, 2003, 04:20:20), Project Version 6.1.064. The LCROSS.py Python script used with GSEOS is Version Jun 11, 2008. The LCROSS Report Generator used on GSEOS created CCSDS.dat files is version 114. The LCROSS Make Archive program used to combine the output from GSEOS, LCROSS.py and LCROSS Report Generator to generate the PDS image and ASCII label files is dated 03/14/2010.
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| DATA_SET_RELEASE_DATE |
2010-03-17T00:00:00.000Z
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| START_TIME |
2009-06-20T02:00:00.000Z
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| STOP_TIME |
2009-10-09T11:36:00.000Z
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| MISSION_NAME |
LUNAR CRATER OBSERVATION AND SENSING SATELLITE
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| MISSION_START_DATE |
2009-04-27T12:00:00.000Z
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| MISSION_STOP_DATE |
2009-10-09T12:00:00.000Z
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| TARGET_NAME |
CALIBRATION
TEST IMAGE
EARTH
MOON
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| TARGET_TYPE |
CALIBRATION
PLANET
SATELLITE
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| INSTRUMENT_HOST_ID |
LCROSS
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| INSTRUMENT_NAME |
NEAR INFRARED CAMERA 1
VISIBLE CAMERA
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| INSTRUMENT_ID |
NIR1
VIS
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| INSTRUMENT_TYPE |
CAMERA
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| NODE_NAME |
Geosciences
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| ARCHIVE_STATUS |
LOCALLY_ARCHIVED
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| CONFIDENCE_LEVEL_NOTE |
Confidence Level Overview : The confidence level is unspecified. Review : This LCROSS data set was reviewed internally by the LCROSS science team before delivery to PDS. This data set has passed a PDS peer review. Data Coverage and Quality : This dataset contains all images taken by LCROSS Visible Camera (VIS) during the mission, in raw form. These images are in focus. Some images in this dataset contain image artifacts caused by interaction between the compression algorithm and the downlink. This occurred during the PREIMPACT and IMPACT data collection periods because the size of the compressed images slightly exceeded the maximum CCSDS packet size. This did not occur during any other data collection periods. These compression artifacts are not flagged in the label files. Limitations : These images are not at the native detector resolution and accuracy because they have passed through an analog format before downlink. Digitizing the analog format on the spacecraft introduced edge pixels that must be clipped before computing image statistics. This clipping is not done in this dataset. Saturated pixels are not flagged. The detector in this camera blumes significantly when overexposed. This occurred during several data collection periods, particularly the EARTHLOOK calibration periods. Images where this occurred are not flagged in the label files. Temporarily hot pixels due to cosmic ray strikes are not not flagged. Rarely, images were lost in decompression on the ground. No significant data was lost this way. Data Compression : The raw visible camera images are compressed using a proprietary, wavelet-based compression algorithm onboard and decompressed on the ground. This compression was lossy. A version mismatch between compression / decompression implementations on the spacecraft and the ground resulted in rare failures to decompress an image.
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| CITATION_DESCRIPTION |
Colaprete, A., Lunar Crater Observation and Sensing Satellite Visible Camera Raw Data V1.0, LCROSS-E/L-VIS-2-RAW-V1.0, NASA Planetary Data System, 2010.
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| ABSTRACT_TEXT |
Raw, uncalibrated image data from the Visible Camera (VIS) aboard the Lunar Crater Observation and Sensing Satellite (LCROSS).
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| PRODUCER_FULL_NAME |
ANTHONY COLAPRETE
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| SEARCH/ACCESS DATA |
LCROSS Analysts Notebook
LCROSS FTP Resource
GEOSCIENCES WEB SERVICES
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