v1.2 2014-03-29
- Moved information from comments into definitions for all attributes.
- Added source product, orbit number and sclk start/stop times.
- Revised some enumerated value options, and corrected some nillable inconsistencies.
v1.3.0 2015-01-23
- Updated to version 1.3.0.1 of IM.
- Added min/max_observed_event_time.
- Included reference_time_UTC as optional attribute for all profile labels.
- Revised some definitions.
v1.4.0.0 2016-04-25
- This version was not released
- Updated to version 1.6.0.0 of IM.
- Corrected case errors in class and attribute names and enumerated values
- Changed several time attribute types from ASCII_Date_Time_UTC to ASCII_Date_Time_YMD_UTC
- revised several definitions
- Changed ring_occultation_direction to occultation_direction, and modified the definitions
for the values ingress and egress.
- Added the class Occultation_Time_Series.
- Combined Radio_Occultation and Stellar_Occultation into Occultation_Ring_Profile
- Renamed Radio_Occultation_Support to Occultation_Supplement
- Removed ring_observation_id and source_pds3_id from all classes except Occultation_Supplement.
- Added Schematron rules to make some optional attributes required based on the value of
occultation type (e.g., dsn_station_number if occultation_type = radio, sub_stellar_ring_azimuth
if occultation_type = stellar).
- Reordered some attributes in Occultation_Time_Series.
- Reordered some attributes in Occultation_Supplement.
v1.5.0.0 2017-04-12
- Changed schema location URLs to https
- Updated to version 1.8.0.0 of IM.
- Revised definition of pds3_source_id
- Corrected the definition of sub_stellar_ring_azimuth
- Changed the name of the umbrella class from Occultation to Ring_Moon_Systems
- Added Time_Series_Direction
v1.5.1.0 2017-08-09
- corrected minor formating errors for a few enumerated values
- Reinstated the ring_plane attribute in the Occultation_Ring_Profile and Occultation_Time_Series classes.
v1.6.0.0 2017-12-13
- Updated to version 1.9.0.0 of IM and version 1.5.1.0 of the geometry dictionary.
- Added the Ring_Model class and numerous classes and attributes to support it.
- Added the Orbital_Elements class.
This class provides the parameters used to
generate a ring model which are specific to the central
body.
This class provides the general parameters used
to generate a ring model.
This class provides the normal mode parameters
is one is present in the described ring.
This class replaces the Radio_Occultation and
Stellar_Occultation classes. It is used for all ring occultation
profiles regardless of the occultation type.
This class is required for all radio ring
occultation calibration and geometry supplemental
files.
This class supports occultation data organized
as a time series.
This class identifies the specific ring to which
the parameters given in the enclosing class
apply.
This class provides the parameters used to
generate a ring model.
This is an umbrella class for all of the classes
and attributes in this dictionary.
This class provides the orbital element values
for a specific ring which were generated in a ring
model.
This class is required for all Rings Node
curated data products
This class identifies the specific satellite to
which the parameters given in the enclosing class
apply.
This class provides the parameters used to
generate a ring model which are specific to a single
satellite.
This section contains the simpleTypes that provide more constraints
than those at the base data type level. The simpleTypes defined here build on the base data
types. This is another component of the common dictionary and therefore falls within the
pds namespace.
along_track_timing_offset is a timing offset to
the along track spacecraft position. It is the value that
minimizes differences in radii of matching circular ring
features observed on the ingress and egress sides of the
occultation track. Optional in labels for radio occultation.
Nillable in which case the nil_reason should be 'inapplicable'.
dsn_station_number identifies the receiving DSN
station. Required in labels for radio occultations; not used for
stellar occultations. Nillable in which case the nil_reason
should be 'inapplicable'.
earth_received_start_time_utc gives the UTC time
corresponding to the earliest time for the data product at which
telemetry or other photons were received on Earth. Optional for
occultation data.
earth_received_stop_time_utc gives the UTC time
corresponding to the latest time for the data product at which
telemetry or other photons were received on Earth. Optional for
occultation data.
The eccentricity of the orbit of the body or
ring identified in the enclosing class.
The uncertainty in the value for the
eccentricity of the orbit of the body or ring identified in the
enclosing class.
The epoch for the ring orbital elements given in
this product. Format is YYYY-MM-DDTHH:MM:SS.SSSZ and may be
truncated.
The RMS residuals for the semimajor axis of the
body or ring identified in the enclosing class.
The frequency_band attribute provides the one
or two letter identifier for the frequency band associated with
radio occultation data. Required in labels for radio
occultations; not used for stellar occultations.
The product of the gravitational constant, G,
and the mass of the body identified in the enclosing class.
The reference radius for the gravitational
harmonic coefficients of the body identified in the enclosing
class.
highest_detectable_opacity indicates the
sensitivity of a ring occultation data set to nearly opaque
rings. It specifies the rough value for the largest normal ring
opacity that can be detected in the data at the resolution
provided, incorporating both statistical effects and calibration
uncertainties. Strongly recommended in labels of ring
occultation observations. Not intended as a value for a table
field.
The inclination of the orbit of the body or ring
identified in the enclosing class.
The uncertainty in the value for the inclination
of the orbit of the body or ring identified in the enclosing
class.
The J2 gravitational harmonic coefficient of the
body identified in the enclosing class.
The J4 gravitational harmonic coefficient of the
body identified in the enclosing class.
The J6 gravitational harmonic coefficient of the
body identified in the enclosing class.
The J8 gravitational harmonic coefficient of the
body identified in the enclosing class.
light_source_incidence_angle is an angle
measured from the local surface normal vector to the direction
of a photon arriving from the light source. For rings, the
normal vector is that on the same side of the rings as the light
source, so values always range between 0 and 90 in units of
degrees. The value is always equal to 90 - |
observed_ring_elevation | This will enable users to perform
database searches based on the effective ring opening angle when
they are not concerned about the the distinction between
north-side and southside viewpoints. We have included the 'light
source' prefix to the term so that this quantity is not confused
with 'incidence angle', a term that is generally associated with
sunlight rather than stars or radio transmitters. Required in
the label if the value is constant for the observation. If the
angle varies for the observation, the min and max attributes are
required in the label. Optional as a field in the data table.
lowest_detectable_opacity indicates the
sensitivity of a ring occultation data set to nearly opaque
rings. It specifies the rough value for the smallest normal ring
opacity that can be detected in the data at the resolution
provided, incorporating both statistical effects and calibration
uncertainties. Strongly recommended in labels of ring
occultation observations. Not intended as a value for a table
field.
maximum_light_source_incidence_angle specifes
the largest value for observed_ring_elevation in the
observation. Only used if the value is not constant over the
observation. Values range from 0 to +90 in units of degrees. Not
intended for use in the data file.
maximum_observed_event_time gives the largest
value for observed_event_time in the associated data file. It is
given in numeric seconds as an offset from the specified UTC
reference time. maximum_observed_event_time is optional in
labels since the data file time interval end point values are
given by the required start_date_time_utc and stop_date_time_utc
attributes in the Time_Coordinates class.
maximum_observed_ring_azimuth specifes the
largest value for observed_ring_azimuth in the data file. Values
range from 0 to 360 in units of degrees. Required in label files
for ring occultation data.
maximum_observed_ring_elevation specifes the
largest value for observed_ring_elevation in the data file. Only
used if the value is not constant over the observation. Values
range from -90 to +90 in units of degrees. Not intended for use
in the data file.
maximum_radial_sampling_interval indicates the
smallest radial spacing between consecutive points in a ring
profile. In practice, this may be somewhat smaller than the
radial_resolution because a profile may be over-sampled. If the
value of radial_sampling_interval varies, the minimum and
maximum attributes are required in labels. Not intended to be
used as a table field.
maximum_ring_longitude specifies one boundary
for the ring longitude range in the data; normally the largest
value. However, for ranges that cross the prime meridian, the
maximum ring longitude will have a value less than the minimum
ring longitude. Values range from 0 to 360 in units of degrees.
Required in label files for ring occultation data.
maximum_ring_radius indicates the largest ring
radius value in the data table. Units are km and are always
positive. Required in label files for ring occultation data.
maximum_wavelength is the largest wavelength
used in the observation. Optional in labels. Used with
minimum_wavelength when the observation is over a wavelength
range.
minimum_light_source_incidence_angle specifes
the smallest value for observed_ring_elevation in the
observation. Only used if the value is not constant over the
observation. Values range from 0 to +90 in units of degrees. Not
intended for use in the data file.
minimum_observed_event_time gives the smallest
value for observed_event_time in the associated data file. It is
given in numeric seconds as an offset from the specified UTC
reference time. minimum_observed_event_time is optional in
labels since the data file time interval end point values are
given by the required start_date_time_utc and stop_date_time_utc
attributes in the Time_Coordinates class.
minimum_observed_ring_azimuth specifes the
smallest value for observed_ring_azimuth in the data file.
Values range from 0 to 360 in units of degrees. Required in
label files for ring occultation data.
minimum_observed_ring_elevation specifes the
smallest value for observed_ring_elevation in the data file.
Only used if the value is not constant over the observation.
Values range from -90 to +90 in units of degrees. Not intended
for use in the data file.
minimum_radial_sampling_interval indicates the
smallest radial spacing between consecutive points in a ring
profile. In practice, this may be somewhat smaller than the
radial_resolution because a profile may be over-sampled. If the
value of radial_sampling_interval varies, the minimum and
maximum attributes are required in labels. Not intended to be
used as a table field.
minimum_ring_longitude specifes one boundary for
the ring longitude range in the data; normally the smallest
value. However, for ranges that cross the prime meridian, the
minimum ring longitude will have a value greater than the
maximum ring longitude. Values range from 0 to 360 in units of
degrees. Required in label files for ring occultation data.
minimum_ring_radius indicates the smallest ring
radius value in the data table. Units are km and are always
positive. Required in label files for ring occultation data.
minimum_wavelength is the smallest wavelength
used in the observation. Optional in labels. Used with
maximum_wavelength when the observation is over a wavelength
range.
The regression rate of the node of the orbit of
the body or ring identified in the enclosing class.
A flag indicating the constraints used to
determine the node regression rate of the orbit of the body or
ring identified in the enclosing class.
The uncertainty in the value for the periapse
precession rate of the orbit of the body or ring identified in
the enclosing class.
The longitude of the ascending node of the orbit
of the body or ring identified in the enclosing class.
The uncertainty in the value for the longitude
of the ascending node of the orbit of the body or ring
identified in the enclosing class.
The amplitude of the normal mode for the ring
identified in the enclosing class. A value of -9.99X10^99
indicates there is no normal mode for the ring.
The uncertainty in the value for the normal mode
of the ring identified in the enclosing class. A value of
-9.99X10^99 indicates there is no normal mode for the ring.
The pattern speed of the normal mode in the ring
identified in the enclosing class. A value of -9.99X10^99
indicates there is no normal mode for the ring.
The the uncertainty in the pattern speed of the
normal mode in the ring identified in the enclosing class. A
value of -9.99X10^99 indicates there is no normal mode for the
ring.
The phase of the normal mode at epoch specified
by epoch_ring_fit_utc for the ring identified in the enclosing
class. A value of -9.99X10^99 indicates there is no normal mode
for the ring.
The uncertainty in the value for the
normal_mode_phase of the ring identified in the enclosing class.
A value of -9.99X10^99 indicates there is no normal mode for the
ring.
The wave number of the normal mode in the ring
identified in the enclosing class. A value of -999 indicates
there is no normal mode for the ring.
Number of fitted data points for the orbit of
the body or ring identified in the enclosing class.
observed_event_start_tdb indicates the value for
earliest time in the described data, and is given in elapsed
seconds since the J2000 epoch. Optional in labels; not intended
for use as a table field.
observed_event_start_time_utc indicates the UTC
value for earliest time in the described data. It is part of a
start/stop pair. If one of observed_event_start_time_utc and
observed_event_stop_time_utc is used, both must be used.
observed_event_stop_tdb indicates the value for
latest time in the described data, and is given in elapsed
seconds since the J2000 epoch. Optional in labels; not intended
for use as a table field.
observed_event_stop_time_utc indicates the UTC
value for latest time in the described data. It is part of a
start/stop pair. If one of observed_event_start_time_utc and
observed_event_stop_time_utc is used, both must be used.
observed_ring_elevation is an angle measured at
a point in the ring plane, starting from the ring plane to the
direction of a photon heading to the observer. This angle is
positive on the side of the ring plane defined by positive
angular momentum, and negative on the opposite side. Values
range from -90 to +90 in units of degrees. This angle is
constant for stellar occultations, but may vary significantly
during radio occultations. Note: The direction of positive
angular momentum points toward the IAU-defined north side of the
ring plane for Jupiter, Saturn and Neptune, but IAU-defined
south side of the ring plane for Uranus. Required in the label
if the value is constant for the observation. If the angle
varies for the observation, the min and max attributes are
required in the label, and observed_ring_elevation is strongly
recommended as a field in the data table. The above definition
of observed_ring_elevation is equivalent to the most common
usage of the term 'ring open angle', B.
occultation_direction indicates the direction of
an occultation track. This refers to the observed occultation
track overall, not to the subset that might appear in a
particular file (e.g., if an occultation includes both ingress
and egress tracks, the value for occultation_direction will be
both in the data products for each occultation profile.
Permitted values are 'Ingress', 'Egress', 'Both', and
'Multiple'. The value 'multiple' is only used for some
Hubble-based occultations where the occultation track is not
monotonic over relatively short time scales. Required in labels
of ring occultation observations. Not intended as a value for a
table field.
occultation_type distinguishes between three
types of occultation experiments: Stellar, Solar, or Radio.
Stellar occultations involve observing a star as a targeted ring
or body passes in front, as seen from either a spacecraft or
Earth-based observatory. Solar occultations are similar to
stellar occultations except that the Sun is used in place of a
star. Radio occultations typically involve observing the
continuous-wave radio transmissions from a spacecraft as it
passes behind the target as seen from a radio telescope on Earth
or another spacecraft. Required in labels of occultation
observations. Normally not intended as a value for a table
field.
orbit_number if present is the value assigned by
the mission for the orbit number associated with the
observation. Optional in labels of occultation observations and
may be used multiple times. Nillable, the nil_reason should be
'inapplicable'. Normally not intended as a value for a table
field.
The longitude of periapse for the orbit of the
body or ring identified in the enclosing class.
The uncertainty in the value for the longitude
of periapse for the orbit of the body or ring identified in the
enclosing class.
The precession rate of the periapse of the orbit
of the body or ring identified in the enclosing class.
A flag indicating the constraints used to
determine the periapse precession rate of the orbit of the body
or ring identified in the enclosing class.
The uncertainty in the value for the periapse
precession rate of the orbit of the body or ring identified in
the enclosing class.
The planetary_occultation_flag is a yes-or-no
flag that indicates whether a occultation track also intersects
the planet. Required in labels of ring occultation observations.
Normally not intended as a value for a table field.
The declination (Dec) of the pole of the
specified body, given in angular measurements.
The uncertainty of the declination (Dec) of the
pole of the specified body, given in angular measurements.
The right ascension (RA) of the pole of the
specified body, given in angular measurements.
radial_resolution indicates the nominal radial
distance over which changes in ring properties can be detected
within a data product. Note: this value may be larger than the
radial_sampling_interval value, because a data product can be
over-sampled. Required in labels if the value is fixed, as it is
for stellar occultations. If the value varies, the corresponding
minimum and maximum attributes must be used instead. Not
intended to be used as a table field.
radial_sampling_interval indicates the radial
spacing between consecutive points in a ring profile. In
practice, this may be somewhat smaller than the
radial_resolution because a profile may be over-sampled.
Required in labels if the value is fixed. If the value varies,
the corresponding minimum and and maximum attributes must be
used instead. Not intended to be used as a table field.
reference_time_utc provides a date and time in
UTC format. Given in a label when time values in a table are
given as elapsed seconds offset from a reference time. Unless
there are compelling reasons to do otherwise, reference_time_utc
should correspond to the start of a day. Required anytime a
table field is given relative to a specific date and time other
than when Barycentric Dynamical Time is used (e.g.,
observed_event_tdb).
ring_event_start_tdb indicates the value for
earliest time in the described data, and is given in
ring_event_tdb format. Optional in labels; not intended for use
as a table field.
ring_event_start_time_utc gives the UTC time
corresponding to the earliest time given by ring_event_time or
ring_event_tdb in the data table. ring_event_start_time_utc is
required for all ring occultation data.
ring_event_start_time_utc is required label attribute for all
ring occultation data.
ring_event_stop_tdb indicates the value for
latest time in the described data, and is given in
ring_event_tdb format. Optional in labels; not intended for use
as a table field.
ring_event_stop_time_utc gives the UTC time
corresponding to the latest time given by ring_event_time or
ring_event_tdb in the data table. ring_event_stop_time_utc is
required for all ring occultation data. ring_event_stop_time_utc
is required label attribute for all ring occultation data.
The ring_observation_id uniquely identifies a
single experiment or observation (image, occultation profile,
spectrum, etc.) within a rings-related data set. This is the
common id by which data are identified within the Rings Node
catalog. It describes the smallest quantity of data that can be
usefully cataloged or analyzed by itself. Note that a single
observation may be associated with multiple data products (e.g.
raw and calibrated versions of an image). Note also that a
single data product may be associated with multiple observations
(e.g. a single WFPC2 image file containing four different
images). A ring observation id is constructed using numbers,
upper case letters, forward slash, colon, period, dash, and
underscore as follows: p/type/host/inst/time/... where p is a
single-letter planet id (one of J, S, U, or N); type is IMG for
images, OCC for occultation profile, etc.; host is the
instrument host id, inst is the instrument id; time is the
observation time as a date or instrument clock count; further
information identifying the observation can then be appended as
appropriate. Optional in labels. Nillable, in which case the
nil_reason should be 'inapplicable'. Examples:
J/IMG/VG2/ISS/20693.01/N J/IMG/VG2/ISS/20693.02/W
S/IMG/HST/WFPC2/1995-08-10/U2TF020B/PC1
U/OCC/VG2/RSS/1986-01-24/S U/OCC/VG2/RSS/1986-01-24/X
N/OCC/VG2/PPS/1989-08-25/SIGMA_SGR
ring_plane indicates the plane upon which
parameters such as ring_radius are based. Possible values for
the Saturn ring system are 'Equator', 'A', 'B', 'C', 'D', 'E',
'F', 'G', 'Phoebe'. For the Uranus ring system values are
'Equator', 'Six', 'Five', 'Four', 'Alpha', 'Beta', 'Eta',
'Gamma', 'Delta', 'Lambda','Epsilon',Nu, Mu. Required in labels
of ring occultation observations.
ring_profile_direction indicates the radial
direction of a ring occultation within a particular data
product. Possible values are 'Ingress', 'Egress', or 'Multiple'.
The value 'Multiple' is only used for some Hubble-based
occultations where the occultation track is not monotonic over
relatively short time scales. Required in labels of ring
occultation observations. Not intended as a value for a table
field.
sclk_start_time is the value of the spacecraft
clock corresponding to the start_date_time given in the label.
sclk_stop_time is the value of the spacecraft
clock corresponding to the stop_date_time given in the label.
The semimajor axis of the orbit of the body or
ring identified in the enclosing class.
The uncertainty in the value for the semimajor
axis of the orbit of the body or ring identified in the
enclosing class.
source_pds3_id is the PDS3 product identifier
for the source product. If the source product has been archived
under PDS4, use the Internal_Reference class in the
Investigation_Area. source_pds3_id is constructed as PDS3
dataset_id, a colon, then the PDS3 product_id. The acceptable
nil_reasons are 'inapplicable' and 'unknown'.
spacecraft_event_start_time_utc gives the UTC
time corresponding to the earliest time given by
spacecraft_event_time in the data table. However, while
spacecraft_event_time is given as seconds offset from a
reference time, spacecraft_event_start_time_utc is given as a
UTC date time. Required in the label for radio occultation data.
Not used for stellar occultations.
spacecraft_event_stop_time_utc gives the UTC
time corresponding to the latest time given by
spacecraft_event_time in the data table. However, while
spacecraft_event_time is given as seconds offset from a
reference time, spacecraft_event_stop_time_utc is given as a UTC
date time. Required in the label for radio occultation data. Not
used for stellar occultations.
spice_filename gives the file name(s) of SPICE
files used in the analysis. Only used if the SPICE files cannot
be identified using a LID or LIDVID. Otherwise the association
is made in the Reference_Class using the Internal_Reference
class. Optional in labels for radio occultation. Nillable in
which case the nil_reason should be 'inapplicable'.
star_name provides the identifying name of star,
including the catalog name if necessary. Examples include 'sigma
Sgr' and 'SAO 123456' (for star number 123456 in the Smithsonian
Astrophysical Observatory catalog). Use 'Sun' for solar
occultations. Required in labels for stellar and solar
occultations. Not used for radio occultations.
sub_stellar_clock_angle is an angle measured at
a point in the ring plane, from the direction toward a star to
the local radial direction. This angle is projected into the
ring plane and measured in the clockwise (retrograde) direction.
Equivalently, this is the prograde angle from the local radial
direction to the direction toward the star. For stellar
occultation data, this angle is equal to (180 -
OBSERVED_RING_AZIMUTH) mod 360. It is available only for
backward compatibility with previously published Cassini VIMS
occultation data analysis; observed_ring_azimuth is the
preferred quantity for archiving. sub_stellar_clock_angle is an
optional data table field for Cassini VIMS occultation data; not
recommended for other occultation data. In a label, the min and
max variation attributes are optional for Cassini VIMS
occultation data; not recommended for other occultation data.
sub_stellar_ring_azimuth is an angle measured at
a point in the ring plane, starting from the direction of a
photon arriving from a star, and ending at the direction of a
local radial vector. This angle is projected into the ring plane
and measured in the prograde direction. Values range from 0 to
360 in units of degrees. For stellar occultation data, this
angle is equal to (observed_ring_azimuth + 180) mod 360. It is
available only for backward compatibility with previously
published Cassini UVIS occultation data analysis;
observed_ring_azimuth is the preferred quantity for archiving.
sub_stellar_ring_azimuth is an optional data table field for
Cassini UVIS occultation data; not recommended for other
occultation data. In a label, the min and max variation
attributes are optional for Cassini UVIS occultation data; not
recommended for other occultation data.
time_series_direction indicates the direction
the occultation proceeds through the target within a particular
data product. Possible values are 'ingress', 'egress', 'both' or
'multiple'. The value 'Multiple' is only used for some
Hubble-based occultations where the occultation track is not
monotonic over relatively short time scales. Not intended as a
value for a table field.
wavelength of the observation. Optional in
labels. If the observation is over a wavelength range, use the
corresponding minimum and maximum attributes instead.