Data Set Overview
    =================
    The Juno Derived Radio Science Gravity Data of Science Data
    Products (SDP) includes data products generated from gravity
    investigations conducted by members of the Juno Gravity
    Science Team. Gravity SDPs include spherical harmonic models
    of Jupiter's gravitational field.

    Parameters
    ==========
    Spherical harmonic models are tables of coefficients GM, Cmn,
    and Smn -- as in equation (1) of [FOLKNER2017]. These can
    be used to represent gravitational potential of Jupiter, for
    example. ASCII (data type SHA) formatted spherical harmonics
    are defined. Each file contains two tables:
    a header table containing general parameters for
    the model (gravitational constant, its uncertainty, degree
    and order of the field, normalization state, reference longitude,
    and reference latitude); and a coefficients table (degree m,
    order n, coefficients Cmn and Smn, and their uncertainties).

    Processing
    ==========
    Spherical harmonic models are derived from raw radio tracking
    data in several steps.

    The tracking data are processed in large orbit determination
    programs that integrate the equations of motion, and model
    mathematically the radio science observables, namely, Doppler
    measurements. The observations are related to
    the geophysical parameters through the numerical integration and the
    detailed mathematical modeling of the radio science observables, and of
    all forces acting on the spacecraft trajectory, including
    planetary and third body gravity, solar radiation pressure,
    planetary radiation pressure, atmospheric drag, solid body tides,
    and relativity, where applicable.

    The gravity field coefficients are obtained by accumulating
    normal equations numerous data arcs, and
    solving these systems of linear equations with many unknowns.
    The unknowns include arc parameters, particular to one data arc (such
    as the spacecraft state, radiation pressure scale factors,
    atmospheric drag scale factors, etc.) and common parameters
    (such as the gravity coefficients, the planetary gravitational
    constant or GM). Radio tracking data are processed in arcs delimited by
    geometric or spacecraft events.

    Specifics on the production of a given gravity field model are best
    understood by reading the appropriate reference paper. Such examples
    for Juno include [FOLKNER2017], [IESS2018], [DURANTE2020], etc.

    Data
    ====
    Data are available online through the Planetary Data System
    (http://pds.nasa.gov).

    ASCII spherical harmonic models are stored in the DATA/SHABDR directory
    with filenames of the form GRV_JUGR_SHA_bbb_z_nnnn_YYYYMMDD_Vvv.TAB where:

      'GRV'    indicates the file is a part of the Juno Gravity Science
               instrument
      'JUGR'   indicates the file is a part of the Juno Gravity Science
               data set
      'SHA'    denotes that this is an ASCII file of Spherical Harmonic
               coefficients
      'bbb'    denotes the body the field is applicable for. variable width.
               valid bodies include:
                      'JUP'  for Jupiter
                      'GAN'  for Ganymede
                      'EUR'  for Europa
                      'IO'   for Io
      'z'      indicates the normalization of the coefficients
                      'U'    for UN-NORMALIZED
                      'N'    for NORMALIZED
      'nnnn'   is a variable-width descriptor of the gravity field
               specified by the data producer. This modifier is used
               to indicate the name of the gravity field model and producer.
      'YYYY'   is the 4-digit gravity field publication year
      'MM'     is the 2-digit gravity field publication month
      'DD'     is the 2-digit gravity field publication day
      'Vvv'    indicates the data product version number
                      e.g. V01 = Version 01
      '.TAB'  indicates the data is stored in tabular form.

    Each SHADR file is accompanied by a detached PDS label; that label is
    a file in its own right, having the same base file name but with the
    '.LBL' extension. The label file contains *IMPORTANT* information
    on the use of the gravity field coefficients stored in the data file.

    Coordinate System
    =================
    Juno Gravity SDP files use a body-centered body-fixed coordinate system
    similar to the IAU coordinate system. The values differ slightly
    because the orientation of Jupiter is estimated in the orbit
    determination process.

    ***THE COORDINATE SYSTEM PARAMETERS ARE DEFINED IN THE LABEL FILE***

    See labels of specific gravity products for details.

    Software
    ========
    None.

    Media/Format
    ============
    This data set is stored online at the Planetary Data System
    (http://pds.nasa.gov/) and may be downloaded using a web browser
    or FTP software. A copy may be requested on physical media if
    downloading is not possible. The Planetary Data System maintains
    backup copies of this data set on various media.

Overview
    ========
    Data in this archive have been reduced as part of mission data
    analysis activities of the Juno Gravity Science Team.

    Review
    ======
    This archival data set was reviewed by the Juno Gravity
    Team prior to submission to the Planetary Data System (PDS).
    Data set design, documentation, and sample products have passed
    a PDS peer review.

    Data Coverage and Quality
    =========================
    This volume contains gravity models generated from radiometric
    tracking of the Juno spacecraft.

    GRV_JUGR_SHA_JUP_U_DUR2020_20200203_V01.TAB is an ASCII file of
    coefficients and related data for a 12th degree Jupiter gravity
    field produced at the Sapienza University of Rome. The archival
    data product was produced by the Jet Propulsion Laboratory
    Planetary Radar and Radio Sciences Group. The name of the
    gravity field model is DURANTE2020. The model used is described
    in the file's detached label.

    Limitations
    ===========
    The limitations in this data set follow from the quality of
    the execution, which is described above under Data Coverage
    and Quality.