Data Set Information
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| DATA_SET_NAME |
ER2 EARTH AVIRIS CALIBRATED REDUCED DATA RECORD IMAGE V1.0
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| DATA_SET_ID |
ER2-E-AVIR-3-RDR-IMAGE-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 Airborne Visible and Infared Imaging Spectrometer (AVIRIS) data are divided into 10x10 square kilometer scenes for purposes of standard product generation. More than 40 scenes were generated during GRSFE, more than 20 of which are included on the CD-ROMs, covering a variety of surfaces. Lunar Crater was covered several times in one day (under clear atmospheric conditions) in order to evaluate atmospheric scattering and absorption removal algorithms and to explore extraction of roughness information using variable incidence angle AVIRIS data. The AVIRIS multi-temporal data were acquired at the same time that ground-based, multi-spectral measurements of atmospheric optical depth, and sky radiance at varying scattering angles were acquired, along with surface bidirectional reflectance data. Accurate wavelength calibration of AVIRIS was performed by JPL using laboratory measurements acquired before and after the AVIRIS flights. An additional check on the wavelength calibration can be made by comparing the positions of known atmospheric absorption features to their locations in actual AVIRIS data. Each AVIRIS scene is calibrated to radiance. The radiance values are stored as 16-bit integers in units of 100 microwatts / (centimeters squared * nanometers * steradians). Each AVIRIS scene is accompanied by 7 ancillary files. They are the navigation, engineering, dark current, offset, dropout, radiometric calibration, and raw spectral calibration files. The navigation file contains the data from the aircraft navigation system. It is recorded by the AVIRIS instrument every major frame. However, it is only updated by the aircraft system every five seconds (60 major frames). It contains the following information: flight id, run id, date, time, latitude, longitude, N-S velocity, E-W velocity, true heading, ground speed, vertical velocity, altitude, true air speed, pitch and roll. The engineering file is from the AVIRIS instrument. It is recorded every major frame and contains the following information: detector temperatures, spectrometer temperatures, scanner optics mount temperature, scan voltages, calibration lamp current, hardware status indicators, scan mirror readings, instrument roll gyro readings, instrument yaw gyro readings, and instrument firmware status indicators. The dark current file contains data taken with the fore-optics shutter closed during scanner flyback and is recorded every major frame. This data has had the initial dark current (offset) data subtracted from it onboard the aircraft. It is therefore a record of how the dark current varies with time over a flight line with respect to the initial dark current. The offset file contains the initial, raw, dark current data taken once, prior to each flight line. It is taken with the fore-optics shutter closed and recorded without any onboard subtraction performed (the same values are recorded every major frame throughout a flight line). This data is subtracted from the image data onboard the aircraft during a flight line in order to keep the image signal level on scale in the signal chain. It is also onboard subtracted from the dark current measurements taken during a flight line. The dropout file contains the data compiled during the logging process. Anomalies in the recording process can cause some lines to contain unintelligible data. These lines are flagged at 4096 DN, and are called dropped lines. The dropout file is a list of those lines that have been flagged. The radiometric calibration file contains the real number calibration coefficients which transform the DN values of the raw image into units of radiance. The units of these coefficients are microwatts per square centimeter per nanometer per steradian per DN. Note that the AVIRIS image data on the GRSFE CD-ROMs are already calibrated and given as radiance values. This data has been adjusted for cross-track vignetting and for offsets between the spectrometers. The raw spectral calibration file contains two real numbers per channel. The first number is the wavelength position corresponding to the channel number, and the second is the full width half max number for the spectral response function of each channel. Processing Level Id : 3 Software Flag : N Processing Start Time : 1989-09-29T00:00:00.000 Processing Stop Time : 1991-05-28T00:00:00.000 Parameters : Data Set Parameter 'RADIANCE' ----------------------------- Radiance is the amount of energy per time per projected area per steradian. Data Set Parameter Name : RADIANCE Data Set Parameter Unit : WATT/(METER*METER)/STERADIAN Sampling Parameter Name : PIXEL Sampling Parameter Unit : METER Minimum Sampling Parameter : N/A Maximum Sampling Parameter : N/A Sampling Parameter Resolution : 56.57 Sampling Parameter Interval : 20 Minimum Available Sampling Int : N/A Noise Level : N/A Source Instrument Parameters : Instrument Host ID : ER-2 Data Set Parameter Name : RADIANCE Instrument Parameter Name : RADIANCE Important Instrument Parameters : 1 Measurement Information : Atmospheric Conditions ---------------------- Not Applicable Source ------ The sunlight reflected from the Earth's surface is the source of the measurement. Calibration Standard -------------------- Not Applicable Wavelength Calibration ---------------------- Not Applicable Processing : Processing History ------------------ Source Data Set ID : N/A Software : UNK Product Data Set ID : ER2-E-AVIR-3-RDR-IMAGE-V1.0
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| DATA_SET_RELEASE_DATE |
1991-05-28T00:00:00.000Z
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| START_TIME |
1989-09-28T07:28:08.000Z
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| STOP_TIME |
1989-10-04T07:40:35.000Z
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| MISSION_NAME |
GEOLOGIC REMOTE SENSING FIELD EXPERIMENT
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| MISSION_START_DATE |
1989-07-01T12:00:00.000Z
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| MISSION_STOP_DATE |
1989-10-31T12:00:00.000Z
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| TARGET_NAME |
EARTH
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| TARGET_TYPE |
PLANET
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| INSTRUMENT_HOST_ID |
ER-2
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| INSTRUMENT_NAME |
AIRBORNE VISIBLE/IR IMAGING SPECTROMETER
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| INSTRUMENT_ID |
AVIR
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| INSTRUMENT_TYPE |
IMAGING SPECTROMETER
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| NODE_NAME |
Geosciences
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| ARCHIVE_STATUS |
ARCHIVED
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| CONFIDENCE_LEVEL_NOTE |
Overview : The signal-to-noise ratio is at least 100:1 at 0.7 micrometers, and at least 50:1 at 2.2 micrometers.
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| CITATION_DESCRIPTION |
Vane, G., ER2 EARTH AVIRIS CALIBRATED REDUCED DATA RECORD IMAGE V1.0, ER2-E-AVIR-3-RDR-IMAGE-V1.0, NASA Planetary Data System, 1991
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| ABSTRACT_TEXT |
The Airborne Visible and Infared Imaging Spectrometer (AVIRIS) data are divided into 10x10 square kilometer scenes for purposes of standard product generation. More than 40 scenes were generated during GRSFE, more than 20 of which are included on the CD-ROMs, covering a variety of surfaces. Lunar Crater was covered several times in one day (under clear atmospheric conditions) in order to evaluate atmospheric scattering and absorption removal algorithms and to explore extraction of roughness information using variable incidence angle AVIRIS data. The AVIRIS multi-temporal data were acquired at the same time that ground-based, multi-spectral measurements of atmospheric optical depth, and sky radiance at varying scattering angles were acquired, along with surface bidirectional reflectance data. Accurate wavelength calibration of AVIRIS was performed by JPL using laboratory measurements acquired before and after the AVIRIS flights. An additional check on the wavelength calibration can be made by comparing the positions of known atmospheric absorption features to their locations in actual AVIRIS data.
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| PRODUCER_FULL_NAME |
GREGG VANE
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| SEARCH/ACCESS DATA |
Geosciences Web Services
Geosciences FTP Resource
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