Data Set Overview
  =================
    The REMS instrument is a meteorological suite of sensors designed
    to provide measurements of air and ground temperatures, wind speed
    and direction, pressure, humidity and ultraviolet radiation.

    The REMS ADR data set contains ancillary data used in the
    processing of REMS data. These data may come from sources external
    to REMS (as is the case of the rover positions), or derived from
    them (the UV dust attenuation is estimated from images of the
    rover cameras). They are bundled together and with the rest of the
    REMS data to make it easier its interpretation and its processing.

    Data is a time ordered sequence of rows organized into several
    tables. Each data product contains one sol worth of activity.


  Parameters
  ==========
    This data set includes the following information:

    - Geometry information: solar longitude angle, solar zenithal
      angle, rover position, rover velocity, rover pitch, rover yaw,
      rover roll, masthead location and arm status. These data are
      provided by NAIF in SPICE kernels.
    - Corrections information: estimated Ultraviolet Sensor signal
      attenuation due to dust deposition.


  Processing
  ==========
    Processing starts with the generation of the REMS EDRs. The REMS
    EDR data products are generated by the MIPL (Multimission Image
    Processing Laboratory) at JPL, under the OPGS, using the telemetry
    processing software called MSLEdrGen. This software will convert
    the binary data received from telemetry to ASCII. EDRs will then
    be retrieved at Centro de Astrobiologia (INTA-CSIC) using the File
    Exchange Interface (FEI).

    EDR data products have a first automatic process using calibration
    data. The result of this is the TELRDR data set, which contains
    electrical magnitudes and thermal data. In parallel, using
    ancillary data provided by JPL (such as rover location, sun
    position) the ADRs (Ancillary Data Records) are generated. EDRs,
    TELRDRs, ADRs, and calibration data are processed together to
    obtain the ENVRDRs.
    
    The level of processing of the ENVRDRs includes environmental
    magnitudes with minimal corrections (mainly based on the
    degradation of the sensors). Finally, applying models developed by
    the REMS team and refining them with the confidence levels, the
    MODRDR data set is created.

    Some of the ADR data, such as the rover and sun geometry, are
    provided directly by NAIF using SPICE. They are converted to ASCII
    tables following the conventions used in the rest of REMS data
    products.

    Other ADR data, such as the Ultraviolet Sensor attenuation
    estimation, implies some processing.Dust attenuation magnitude
    over the Ultraviolet Sensor is estimated from rover cameras images
    taken at several moments during the mission. The cameras will take
    images of a target of the same size of the photodiodes situated
    near them. With a robust image processing algorithm it will be
    possible to estimate this attenuation factor.


  Data
  ====
    Each REMS ADR product in the data set is concatenation of ASCII
    tables. Each table contains similar ancillary data.

    There are two tables: one for geometry information and another one
    for corrections. Each one contains the information outlined in the
    Parameters section above.

    Columns are delimited by commas and are of fixed length. Rows are
    time ordered and are separated by a carriage return/line
    feed. Each table contains a sol of measurements.


  Coordinate System
  =================
    This data set depends on several coordinate systems used in the MSL
    project. These are:

    - MSL_TOPO frame, fixed to landing site, is used to define rover
      position.
    - MSL_LOCAL_LEVEL, fixed to the rover, is used to define rover
      orientation (roll, pitch and yaw angles)
    - MSL_RSM_ZERO_AZ frame, fixed to the rover, is used to define
      rover remote sensor mast (RSM) azimuth.
    - MSL_RSM_ZERO_EL, fixed to the rover, is used to define rover
      remote sensor mast (RSM) elevation.
    - MSL_ROVER_MECH, fixed to the rover, is used to define Sun
      position angles (azimuth and elevation)


  Software
  ========
    No software is provided in this data set. The RDR tables are simple
    ASCII files that can be displayed on UNIX, Macintosh, and PC
    platforms with common software.

Confidence Level Overview
  =========================
    In this data set, confidence depends on the reliability of the
    data coming from the external sources. In the case of geometry,
    data are SPICE kernels provided by NAIF. They are expected to be
    released as a separate data set. In the case of dust corrections,
    they are dependent on the quality of the rover cameras images and
    on the algorithm developed at CAB.


  Data Coverage and Quality
  =========================
    At the time of this release, due to the low number of images of
    the Ultraviolet Sensor from sols 1 to sol 154, and the ongoing
    work of the signal attenuation estimation algorithm, the
    UV_DUST_ATTENUATION column is set to 1 (no attenuation) as a
    current best estimate. This factor may be updated as soon as
    there is more information available.

    However, analysis of available data has revealed that the
    accumulation of dust over the Ultraviolet Sensor after sol 155
    causes it to be attenuated above 10%, which is beyond the sensor
    operational requirements. When that happens, the
    UV_DUST_ATTENUATION column is set to NULL.


  Limitations
  ===========
    The major limitation of this data set is its dependency on
    external sources.