Data Set Overview
    =================
 
    This data set contains raw mask data from Near Infrared
    Spectrometer #2 on the LCROSS spacecraft from which
    full-resolution, hadamard-mode spectra can be assembled.
    The dataset contains one table per data collection
    period.  Each table contains one row per
    full-resolution, Hadamard spectrum captured during that
    collection period.  Each row contains a timestamp and
    256 values corresponding to 256 distinct configurations
    of the MEMS mask within the spectrometer.
 
    Conversion of raw mask data into raw spectra is
    deterministic and involves no calibration inputs.
    However, this form of the data makes some attributes
    more apparent.  In particular, the check for saturation
    is done on this form.
 
    The timestamp used in each row of these tables is the
    uncorrected spacecraft time which appears in the labels
    for the raw and calibrated spectra as the
    SPACECRAFT_CLOCK_STOP_COUNT attribute.
 
    This dataset encompasses all pre-hadamard mask data
    collected by NSP2 during the mission.  Note that the
    archive's DATA directory is partitioned initially by
    payload data collection period.  The data collection
    period called 20091009113022_IMPACT contains the data
    from one minute prior to the Centaur impact through the
    end of the mission.  Other data collection periods
    periods contain data from various calibration targets.
 
    Related Data Sets
    =================
 
    This dataset is closely related to the NSP2_RAW and
    NSP2_CAL datasets.
 
    Parameters
    ==========
 
       Science
       -------
 
       No instrument parameters vary within this dataset.
       The integration time is uniformly 0.5 seconds.
 
       Housekeeping
       ------------
 
       Instrument temperature at the data collection time is
       reported in the label file under:
       INSTRUMENT_TEMPERATURE and
       INSTRUMENT_TEMPERATURE_COUNT in degrees Centigrade
       and raw counts, respectively.  This is a single
       telemetry point most representative of the
       instrument chassis temperature.
 
    Processing
    ==========
 
    Each near-infrared spectra was digitally transmitted
    from the spectrometer to the spacecraft in its raw
    format, inserted into a packet uncompressed and
    downlinked in telemetry.  On the ground, the spectra
    were extracted from telemetry, and they were converted
    to CSV format.  For each data collection period, the
    LCROSS Make Archive program read these files and wrote
    them as a PDS-formatted table (.TAB) and label (.LBL)
    file.
 
    Data
    ====
 
    The files in this dataset are PDS-formatted, ascii,
    single-column tables with detached label files.
 
    Coordinate System
    =================
 
    The label files for these spectra contain the
    spectrometer's boresight vector in J2000 Geocentric
    Inertial frame.
 
    Software
    ========
 
    The GSEOS Version used to generate these spectra 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 version of Satellite Toolkit used to prepare geometric
    information for the labels is 8.1.3.
 
    The LCROSS Make Archive program used to assemble the
    PDS-formatted submission is dated 03/14/2010.

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 data path from spectrometer to PDS involved no
    lossy compression and was fully error corrected.  No
    NSP2 packets were lost in downlink.  No NSP2 spectra
    were saturated.
 
    Limitations
    ===========
 
    At low signal to noise ratios, detector noise in the
    pre-hadamard data can result in negative raw counts for
    some pixels.  These values are not physical but are
    effectively a feature of the internally-performed dark
    subtraction inherent in this spectrometer's design.
 
    Data Compression
    ===============
 
    No data compression was used in the datapath from the
    detector to the formatted files ready for submission to
    the PDS.