Data Set Information
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| DATA_SET_NAME |
ARECIBO VENUS RADIO TELESCOPE RESAMPLED 12.6 CM RADAR V1.0
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| DATA_SET_ID |
ARCB-V-RTLS-4-12.6CM-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 : The Arecibo 12.6 cm radar data set for Venus consists of scaled radar backscatter cross section images generated from data obtained in 1983 and 1988. The images are in raster format (one image per record, with no embedded labels). The original images are in 16-bit, unsigned integer, most-significant-byte-first format. Since the volume of the entire set of 16-bit images would have exceeded the capacity of the CD-ROM, some of the images have been scaled to 8-bit versions. Specifically, the entire set of 1988 images are in the scaled 8-bit format, while all the 1983 images are in the original 16-bit format. Both the 16-bit and the 8-bit images were provided by Don Campbell, Cornell University. The 1983 data (acquired in August) cover parts of the northern hemisphere of Venus and consist of 4 files. The first is a mosaic in a Mercator projection with a pixel spacing of 0.12 degrees in longitude. A grid spaced at 10 degrees in both latitude and longitude is embedded in the data. The remaining three files are sections of the mosaic. The mosaic covers 18 to 80 degrees north latitude and 250 (leftmost) to 40 (rightmost) degrees east longitude. The three sections of the 1983 mosaic cover the following areas: (a) 18 to 70 north latitude, 320 to 40 east longitude; 0.02 degrees long pixel spacing; (b) 69 to 80 north latitude, 267 to 21 east longitude, 0.04 degrees long pixel spacing; (c) 18 to 70 north latitude, 250 to 331 east longitude, 0.02 degrees longitude pixel spacing. The data correspond to incidence angle ranges of 44 to 70 degrees, relative to the sub-Earth point. Polarization is circular, with opposite sense receive, so the data consist of polarized returns. For the mosaic, a theoretical antenna beam pattern has been removed and the echoes have been corrected for a diffuse scattering law by multiplying by the cosine of the incidence angle. Data have been scaled to fit within a 16 bit interval. The 1988 data consist of two groups of images that cover the northern and southern hemispheres. Twenty-five individual 'looks' were averaged to make each northern hemisphere image, whereas 26 looks were averaged for the southern hemisphere images. Incidence angles for most of the coverage are between 20 and 60 degrees; the extreme range is from 8 to 67 degrees. Ground resolution is between 1.5 and 2 km. The range resolution varies from 1.7 km at 20 degrees incidence to 0.8 km at 50 degrees; the Doppler resolution (approximately east-west) is about 1.3 km. Processing Level Id : 4 Software Flag : N Processing Start Time : 1983 Processing Stop Time : 1990 Parameters : Data Set Parameter 'RADAR SCALED BACKSCATTER CROSS SECTION' ----------------------------------------------------------- Cross section values that are scaled by some procedure, such as dividing by theoretical or empirical scattering laws. Data Set Parameter Name : RADAR SCALED BACKSCATTER CROSS SECTION Data Set Parameter Unit : DIMENSIONLESS Sampling Parameter Name : PIXEL Sampling Parameter Unit : N/A Minimum Sampling Parameter : N/A Maximum Sampling Parameter : N/A Sampling Parameter Resolution : N/A Sampling Parameter Interval : N/A Minimum Available Sampling Int : N/A Noise Level : UNK Source Instrument Parameters : Instrument Host ID : ARCB Data Set Parameter Name : RADAR SCALED BACKSCATTER CROSS SECTION Instrument Parameter Name : RADAR ECHO POWER Important Instrument Parameters : 1 Measurement Information : Atmospheric Conditions ---------------------- NOT APPLICABLE Source ------ The observations used the 300 meter reflector at Arecibo for transmission. Calibration Standard -------------------- NOT APPLICABLE Wavelength Calibration ---------------------- Transmitter frequency calibrated with a hydrogen maser. Processing : N/A
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| DATA_SET_RELEASE_DATE |
1990-06-15T00:00:00.000Z
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| START_TIME |
1983-08-01T12:00:00.000Z
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| STOP_TIME |
1988-06-20T12:00:00.000Z
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| MISSION_NAME |
PRE-MAGELLAN
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| MISSION_START_DATE |
1968-11-09T12:00:00.000Z
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| MISSION_STOP_DATE |
1988-07-27T12:00:00.000Z
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| TARGET_NAME |
VENUS
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| TARGET_TYPE |
PLANET
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| INSTRUMENT_HOST_ID |
ARCB
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| INSTRUMENT_NAME |
RADIO TELESCOPE
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| INSTRUMENT_ID |
RTLS
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| INSTRUMENT_TYPE |
RADAR
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| NODE_NAME |
Geosciences
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| ARCHIVE_STATUS |
ARCHIVED
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| CONFIDENCE_LEVEL_NOTE |
Overview : 1988 data have several areas where the image is degraded due to cross coupling of power from high backscatter cross section features at the ambiguity location in the opposite hemisphere.
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| CITATION_DESCRIPTION |
Campbell, D. B., ARECIBO VENUS RADIO TELESCOPE RESAMPLED 12.6 CM RADAR V1.0, ARCB-V-RTLS-4-12.6CM-V1.0, NASA Planetary Data System, 1990
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| ABSTRACT_TEXT |
The Arecibo 12.6 cm radar data set for Venus consists of scaled radar backscatter cross section images generated from data obtained in 1983 and 1988. The images are in raster format (one image per record, with no embedded labels). The original images are in 16-bit, unsigned integer, most-significant-byte-first format. Since the volume of the entire set of 16-bit images would have exceeded the capacity of the CD-ROM, some of the images have been scaled to 8-bit versions. Specifically, the entire set of 1988 images are in the scaled 8-bit format, while all the 1983 images are in the original 16-bit format. Both the 16-bit and the 8-bit images were provided by Don Campbell, Cornell University.
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| PRODUCER_FULL_NAME |
DONALD B. CAMPBELL
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| SEARCH/ACCESS DATA |
Geosciences Web Services
Geosciences FTP Resource
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