MECA Optical Microscope (OM) data sets

MISSION specific

PHX

PHX-M-OM-3-RADIOMETRIC-SCI-V1.0

PHOENIX MARS MECA OPTICAL MICROSCOPE 3 RADIOMETRIC SCI V1.0

The Robotic Arm Camera (RAC) experiment on the Mars Phoenix Lander consists of one instrument component plus command electronics. This RAC Imaging Operations RDR data set contains radiometric data from the Robotic Arm Camera (RAC).

Data Set Overview

This data set contains data to help understand the morphology, reflectance and texture of Martian soil and dust at the microscopic scale (typically in the range 10 - 100 microns). In most cases full-frame images with full pixel resolution will be acquired. In some cases, as e.g. for AFM context, the images will be subframed. Onboard downsampling is available, but will not be used during normal operations. Null strip (containing information on bias and system noise) and dark strip (information on dark current) are returned as a separate product if requested.

Processing

This data set uses the Committee on Data Management and Computation (CODMAC) data level numbering system. The Phoenix EDRs are considered CODMAC Level 2 (equivalent to NASA Level 0) or Edited Data (i.e. cleaned, time-ordered and quality-flagged data). The EDRs are reconstructed from Level 1 or Raw Data, which are the telemetry packets within the project specific Standard Formatted Data Unit (SFDU) record. They are assembled into complete images, but are not radiometrically or geometrically corrected. Phoenix EDR data products were generated by the Multi-mission Image Processing Lab (MIPL) at the Jet Propulsion Laboratory. The EDRs are raw uncalibrated data reconstructed from telemetry packet SFDUs and formatted according to the Camera EDR Software Interface Specification (SIS). Meta-data acquired from the telemetry data headers and a meta-data database were used to populate the PDS label. There will not be multiple versions of a Phoenix Camera EDR. Missing packets will be identified and reported for retransmission to the ground as partial datasets. Prior to retransmission, the missing EDR data will be filled with zeros. The EDR data will be reprocessed only after all partial datasets are retransmitted and received on the ground. In these cases, the original EDR version will be overwritten. The EDR data product will be placed into the File Exchange Interface (FEI) for distribution.

Data

The OM data files will be decoded, decompressed camera image data in single frame form as an Experiment Data Record (EDR). The image data are acquired as 12-bit data, but stored as 16-bit signed integers. There are three data types:

  1. Full Frame EDRs Each Full Frame EDR contains a 512 columns * 256 rows image array. The size of a Full Frame EDR data product is therefore approximately 2.1 Mb (260 kB).

  2. Subframe EDRs Subframe EDRs are intended to provide context for the AFM data.

  3. Null & Dark Strip EDRs Each Null & Dark Strip EDR contains a 16 columns * 256 rows array. The pixel values are stored as 16-bit signed integers. The first and last 4 columns are pre-pixels (obtained by reading out 'virtual pixels' without vertical shift) and contain information on the bias value and system noise. The central 8 columns are masked pixels that contain information on the dark current. Null & Dark Strip EDRs are not available for each and every Full Frame EDR, but will only be generated and downlinked occasionally upon request.

Ancillary Data

No ancillary data are needed to understand OM EDRs. Rotation and translation positions of the sample wheel are specified in units of motor step numbers in the EDR label. The Phoenix Project Software Interface Specification (SIS) for Camera Data Products provides the necessary information to convert rotation position step numbers into substrate IDs.

Software

PDS-labeled images and tables can be viewed with the program NASAView, developed by the PDS and available for a variety of computer platforms from the PDS web site http://pdsproto.jpl.nasa.gov/Distribution/license.html. There is no charge for NASAView.

Media/Format

The data set will initially be delivered and kept online. Upon Mission completion, the OM EDRs will be delivered to PDS on DVD as part of the complete Phoenix EDR data set.

PHX-M-OM-2-EDR-V1.0

PHOENIX MARS MECA OPTICAL MICROSCOPE 2 EDR VERSION 1.0

The Microscopy, Electrochemistry, and Conductivity Analyzer (MECA) experiment on the Mars Phoenix Lander consists of four instrument components plus command electronics. This MECA Imaging EDR data set contains data from one of the four MECA components, the Optical Microscope (OM).

Data Set Overview

This data set contains data to help understand the morphology, reflectance and texture of Martian soil and dust at the microscopic scale (typically in the range 10 - 100 microns). In most cases full-frame images with full pixel resolution will be acquired. In some cases, as e.g. for AFM context, the images will be subframed. Onboard downsampling is available, but will not be used during normal operations. Null strip (containing information on bias and system noise) and dark strip (information on dark current) are returned as a separate product if requested.

Processing

This data set uses the Committee on Data Management and Computation (CODMAC) data level numbering system. The Phoenix EDRs are considered CODMAC Level 2 (equivalent to NASA Level 0) or Edited Data (i.e. cleaned, time-ordered and quality-flagged data). The EDRs are reconstructed from Level 1 or Raw Data, which are the telemetry packets within the project specific Standard Formatted Data Unit (SFDU) record. They are assembled into complete images, but are not radiometrically or geometrically corrected. Phoenix EDR data products were generated by the Multi-mission Image Processing Lab (MIPL) at the Jet Propulsion Laboratory. The EDRs are raw uncalibrated data reconstructed from telemetry packet SFDUs and formatted according to the Camera EDR Software Interface Specification (SIS). Meta-data acquired from the telemetry data headers and a meta-data database were used to populate the PDS label. There will not be multiple versions of a Phoenix Camera EDR. Missing packets will be identified and reported for retransmission to the ground as partial datasets. Prior to retransmission, the missing EDR data will be filled with zeros. The EDR data will be reprocessed only after all partial datasets are retransmitted and received on the ground. In these cases, the original EDR version will be overwritten. The EDR data product will be placed into the File Exchange Interface (FEI) for distribution.

Data

The OM data files will be decoded, decompressed camera image data in single frame form as an Experiment Data Record (EDR). The image data are acquired as 12-bit data, but stored as 16-bit signed integers. There are three data types:

  1. Full Frame EDRs Each Full Frame EDR contains a 512 columns * 256 rows image array. The size of a Full Frame EDR data product is therefore approximately 2.1 Mb (260 kB).

  2. Subframe EDRs Subframe EDRs are intended to provide context for the AFM data.

  3. Null & Dark Strip EDRs Each Null & Dark Strip EDR contains a 16 columns * 256 rows array. The pixel values are stored as 16-bit signed integers. The first and last 4 columns are pre-pixels (obtained by reading out 'virtual pixels' without vertical shift) and contain information on the bias value and system noise. The central 8 columns are masked pixels that contain information on the dark current. Null & Dark Strip EDRs are not available for each and every Full Frame EDR, but will only be generated and downlinked occasionally upon request.

Ancillary Data

No ancillary data are needed to understand OM EDRs. Rotation and translation positions of the sample wheel are specified in units of motor step numbers in the EDR label. The Phoenix Project Software Interface Specification (SIS) for Camera Data Products provides the necessary information to convert rotation position step numbers into substrate IDs.

Software

PDS-labeled images and tables can be viewed with the program NASAView, developed by the PDS and available for a variety of computer platforms from the PDS web site http://pds/tools/nasa-view.shtml. There is no charge for NASAView.

Media/Format

The data set will initially be delivered and kept online. Upon Mission completion, the OM EDRs will be delivered to PDS on DVD as part of the complete Phoenix EDR data set.

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