2020 12
Added the attributes: data_quality_index, ring_detected.
Revised the case of several attribute enumerated values from Title case to all lower case. The named
rings of Saturn are in title case while those of Uranus are lower case, consistent with normal usage
by the community.
Added attributes min/max ring_longitude and observed_ring azimuth to Occultation_Time_Series
2019 03
An issue within LDDTool means that currently the tool does not
support referencing classes or attributes from other Discipline namespaces
A fix to LDDTool is in work, but in the interim we borrow classes and
attributes from the geometry dictionary and redefine them here. The
blocks of such borrowed classes and attributes are preceded and followed
by xml comments which include '@@@'
2018 07-17
Classes borrowed from the geom namespace
- Body_Ident_Base --> Body_Ident_Base
- Frame_Ident_Base --> Frame_Ident_Base
- Reference_Frame_Ident --> Reference_Frame_Ident
- Central_Body_Ident --> Central_Body_Ident
- Display_Direction
attributes borrowed from the geom namespace
- body_spice_name
- frame_spice_name
- horizontal_display_axis
- horizontal_display_direction
- vertical_display_axis
- vertical_display_direction
Once LDDTool is repaired the preceding classes and attributes will be
removed and the following will be valid.
Classes used from the geom namespace
- Body_Ident_Base
- Reference_Frame_Ident
- Central_Body_Ident
- Display_Direction
Classes used from the pds namespace
- Internal_Reference
Attributes used from the pds namespace
- local_identifier_reference
- sampling_parameter_name
- sampling_parameter_unit
- sampling_parameter_interval
- description
- name (indirectly via classes from the geom namespace)
- comment (indirectly via classes from the geom namespace)
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 2019-03-06
- Updated to version 1.9.0.0 of IM.
- Added the Ring_Model class and numerous classes and attributes to support it.
- Added the Orbital_Elements class.
- ring_event_tdb - changed the enumeration flag to false
- added optional description attribute to several classes
- added classes to support ring mosaics: Ring_Reprojection and Reprojection_Geometry.
- added several attributes to support ring mosaics.
- Added Display_Direction including pds:local_identifier_reference with a cardinality of [0,*].
- Added the class Ring_Spectrum
- Added attributes
- emission angle
- ring_intercept_resolution
- ring_longitude_observed_minus_subsolar
- reflectivity
- Added an optional pds.local_identifier attribute to most classes.
- As an interim bandaid(?) pending repair of LDDTool, added several classes
and attributes 'borrowed' from the geometry dictionary and removed the
geom. prefixes to those classes in this dictionary. The affected classes
are:
- Body_Ident_Base
- Frame_Ident_Base (not used explicitly when geom is referenced)
- Reference_Frame_Ident
- Central_Body_Ident
- Added Uniformly_Sampled_Radius based on Uniformly_Sampled_Wavelength from the sp namespace
- Made the use of ring_observation_id optional.
- @@@ Need schematron rule to ensure values for axis_name correspond to entries in Axis_Array.name
v1.7.0.0 2019-03-07
- Updated to version 1.10.0.0 of IM.
- Removed the Rings_Supplement class.
- Removed the ring_observation_id attribute.
- Removed pds:Internal_Reference from the Body_Ident_Base and Frame_Ident_Base classes.
- Added a SChematron definition for a value in reference_type in pds:Internal_Reference in Uniformly_Sampled_Radius
v1.8.0.0 2020-01-28
- Updated to version 1.12.0.0 of IM.
- Made Ring_Moon_Systems class the only xsi element.
- removed the attribute source_pds3_id and spice_filename
- removed milable from orbit_number and along_track_timing.
- Added attributes fresnel_scale, projected_star_diameter, sigma_projected_star_diameter, fractional_error_star_counts,
time_constant_type, time_constant, sigma_time_constant.
- All 7 of the preceding were added as optional attributes in the Occultation_Time_Series class
v1.9.0.0 2020-01-31
- Updated to version 1.13.0.0 of IM.
- Add Units of Measure Type = Gmass to the gmass attribute.
v1.10.0.0 2020-06-25
- Updated to version 1.14.0.0 of IM.
- Added the attributes: data_quality_index, ring_detected.
- Revised the case of several attribute enumerated values from Title case to all lower case. The named rings of
Saturn are in title case while those of Uranus are lower case, consistent with normal usage by the community.
- Added attributes min/max ring_longitude and observed_ring azimuth to Occultation_Time_Series.
- Expanded definitions of highest and lowest detectable opacity. In each, set the minimum value to -1.0 which
indicates the signal was too poor to allow the calculation of the value.
The Body_Ident_Base class provides multiple
attributes that can be used to identify a physical object
(spacecraft, planet instrument, transmitter, system barycenter,
etc.). At least one must be used.
The Central_Body_Ident class uniquely identifies
the body that is the central body associated with an observation
(e.g., Saturn for Saturn system observations).
This class provides the parameters used to
generate a ring model which are specific to the central
body.
The Display_Direction class specifies which two
of the dimensions of an Array object should be displayed and how
they should be displayed in the vertical (line) and horizontal
(sample) dimensions of a display device. This class is a
modification of the corresponding class in the Display
Dictionary, and is redefined here for convenience. The
local_identifier_reference is used to identify the array or
arrays to which this iteration of the class applies. Multiple
entries are permitted the settings in the iteration of
Display_Direction apply to all of the referenced arrays.
The Frame_Ident_Base class provides multiple
attributes that can be used to identify a reference frame. At
least one must be used.
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.
The Reference_Frame_Ident class is a base class
for identifying reference frames. These are frames in the NAIF
sense, i.e., three orthogonal axes with a specified orientation,
but without a fixed origin.
This class provides the parameters describing
reprojection geometry when the ring(s) is reprojected based on a
fixed grid of coordinates (.g., radius vs.
longitude).
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 provides the parameters used to
describe ring reprojection geometry.
This class provides the parameters used to
describe ring spectra or spectrograms.
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.
The Uniformly_Sampled_Radius class provides
attributes describing the spectral characteristics of an axis of
an Array object or the rows of a Table object, in cases where
the spectral sampling interval is regular and the sampling
parameters are in wavelength units. The axis is identified
either by using Local_Internal_Reference, or by using axis name.
The latter may be simpler to use if this class applies to
multiple Array objects.
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
common 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.
The axis_name attribute contains a string that
matches the axis_name attribute in an axis_array class of an
associated array object.
The body_spice_name attribute is a
NAIF-recognized string identifier for a physical object
(spacecraft, planet, instrument transmitter, system barycenter,
etc.), associated with the data.
The corotating_flag is a yes-or-no flag that
indicates whether or not a corotating frame is used. a table
field.
The co-rotation rate associated with the data.
data_quality_index provides a more precise
subjective assessment by the data provider of the quality of the
observed/predicted ring occultation. Possible values are:.
data_quality_score indicates the overall quality
of the data, based on a subjective evaluation by the data
provider. Required in labels of ring occultation radial
profiles. Normally not intended as a value for a table field.
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 emission_angle element provides the value of
the angle between the surface normal vector at the intercept
point and a vector from the intercept point to the spacecraft.
Higher values of emission_angle indicate more oblique viewing of
the target. The emission_angle varies from 0 degrees when the
spacecraft is viewing the subspacecraft point (nadir viewing) to
90 degrees when the intercept is tangent to the surface of the
target body, values in the range of 90 to 180 degrees are
possible for ring data.
The basis epoch for the reprojection used in
this product. Format is YYYY-MM-DDTHH:MM:SS.SSSZ and may be
truncated.
The epoch for the ring orbital elements given in
this product. Format is YYYY-MM-DDTHH:MM:SS.SSSZ and may be
truncated.
The first_ring_radius attribute provides the
value of the first increment along the radius axis of an array
given in units of length.
The RMS residuals for the semimajor axis of the
body or ring identified in the enclosing class.
fractional_error_star_counts indicates the
fractional error (1-sigma) in star counts used for square-well
model fit.
The frame_spice_name attribute is a
NAIF-recognized string identifier for a reference frame
associated with the data.
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.
fresnel_scale is sqrt(lambda * D/2), where
lambda is the central wavelength of the observation and D is the
average distance between the observer and the occulting ring.
This is an average value for the entire occultation and is a
measure of the limit on the radial resolution of ring structure
due to diffraction. Note that the actual overall resolution is
affected as well by the projected diameter of the occulted star
and the instrumental time constant, if any.
The product of the Gravitational constant and
the mass of the identified body.
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. -1.0 indicates the signal was too poor to allow
the calculation of the value. Strongly recommended in labels of
ring occultation observations. Not intended as a value for a
table field.
The horizontal_display_axis attribute
identifies, by name, the axis of an Array (or Array subclass)
that is intended to be displayed in the horizontal or "sample"
dimension on a display device. The value of this attribute must
match the value of one, and only one, axis_name attribute in an
Axis_Array class of the associated Array.
The horizontal_display_direction attribute
specifies the direction across the screen of a display device
that data along the horizontal axis of an Array is supposed to
be displayed.
The incidence_angle element provides a measure
of the lighting condition at the intercept point. Incidence
angle is the angle the surface normal vector at the intercept
point and a vector from the intercept point to the sun. The
incidence_angle varies from 0 degrees when the intercept point
coincides with the subsolar point to 90 degrees when the
intercept is tangent to the surface of the target body, values
in the range of 90 to 180 degrees are possible for ring data.
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.
The last_ring_radius attribute provides the
value of the last increment along the radius axis of an array
given in units of length.
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 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. -1.0 indicates the signal was too poor to allow
the calculation of the value. Strongly recommended in labels of
ring occultation observations. Not intended as a value for a
table field.
The maximum value in this product for ring
longitude in the rotating frame. The with zero longitude defined
at the epoch specified by epoch_reprojection_basis_utc, zero
longitude in the corotating frame at time t corresponds to an
inertial longitude of (t-epoch)*corotation_rate.
The maximum_emission_angle element provides the
largest value during the observation for the emission angle at
the target.
The maximum_incidence_angle element provides the
largest value during the observation for the incidence angle at
the target.
maximum_light_source_incidence_angle specifes
the largest value for light_source_incidence_angle 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.
The maximum_phase_angle element provides the
largest value during the observation for the phase angle at the
target.
maximum_radial_resolution indicates the maximum
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. If the value of radial resolution varies,
the minimum and maximum radial resolution attributes are
required in labels. Not intended to be used as a table field.
maximum_radial_sampling_interval indicates the
largest 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_reflectivity indicates the largest value
of I/F within the data object.
maximum_ring_intercept_resolution indicates the
largest value for ring_intercept_resolution in the data product.
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_longitude_observed_minus_sub-solar
specifes smallest separation in ring longitude between the
observation and the subsolar point.
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.
mean_observed_ring_elevation specifes the mean
value for observed_ring_elevation in the data file.
The mean_phase_angle element provides the mean
value during the observation for the phase angle at the target.
The minimum value in this product for ring
longitude in the rotating frame. The with zero longitude defined
at the epoch specified by epoch_reprojection_basis_utc, zero
longitude in the corotating frame at time t corresponds to an
inertial longitude of (t-epoch)*corotation_rate.
The minimum_emission_angle attribute provides
the smallest value during the observation for the emission angle
at the target.
The minimum_incidence_angle attribute provides
the smallest value during the observation for the incidence
angle at the target.
minimum_light_source_incidence_angle specifes
the smallest value for light_source_incidence_angle 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.
The minimum_phase_angle attribute provides the
smallest value during the observation for the phase angle at the
target.
minimum_radial_resolution indicates the minimum
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. If the value of radial resolution varies,
the minimum and maximum radial resolution attributes are
required in labels. Not intended to be used as a table field.
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_reflectivity indicates the largest value
of I/F within the data object.
minimum_ring_intercept_resolution indicates the
smallest value for ring_intercept_resolution in the data
product.
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_longitude_observed_minus_subsolar
specifes smallest separation in ring longitude between the
observation and the sub-solar point. 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 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 used where the occultation
track is not monotonic over relatively short time scales.
Generally only used for some Hubble-based occultations. May be
appropriate for extremely long duration occultations of a high
proper motion star (e.g., u36). 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.
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.
The uncertainty of the right ascension (RA) of
the pole of the specified body, given in angular measurements.
projected_star_diameter provides the projected
angular diameter of the occulted star, from observer to
occulting object.
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).
reflectivity indicates I/F, a dimensionless
standardized measure of reflectivity that is unity for a
Lambertian surface viewed at normal incidence.
reprojection_plane identifies the plane onto
which the reprojection is based. Possible values for the Saturn
ring system are 'Equator', 'Laplace', 'A', 'B', 'C', 'D', 'E',
'F', 'G', 'Phoebe'. For the Uranus ring system values are
'Equator', 'Laplace', 'Six', 'Five', 'Four', 'Alpha', 'Beta',
'Eta', 'Gamma', 'Delta', 'Lambda','Epsilon',Nu, Mu. Required in
labels of ring reprojection products.
The ring_detected attribute is a yes-or-no flag
that indicates whether a specific ring has been detected.
Typically used in radial profiles of a single ring.
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.
ring_intercept_resolution is the size of edge of
a pixel at the distance of the ring intercept point. If the
pixel shape is not square, it is defined by the smaller of the
two edges. Unlike the quantity ‘radial resolution’, these values
are not projected into the ring plane.
ring_longitude specifies the inertial longitude
of a ring feature relative to the prime meridian. In planetary
ring systems, the prime meridian is the ascending node of the
planet's invariable plane on the Earth's mean equator of J2000.
Longitudes are measured in the direction of orbital motion along
the planet's invariable plane to the ring's ascending node, and
thence along the ring plane. Values range from 0 to 360 in units
of degrees. Note: The invariable plane of a planet is equivalent
to its equatorial plane for every ringed planet except Neptune.
Required to be the second field in ring occultation profiles. In
labels, the min and max attributes are required.
ring_longitude_observed_minus_subsolar providees
the difference between the inertial ring longitude of the
observation and inertial ring longitude of the sub-solar point.
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. An additional
value, 'individual' is also defined. Note that the named rings
of Saturn are in title case while those of Uranus are lower
case, consistent with normal usage by the community. 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 used where the occultation track is not
monotonic over relatively short time scales. Generally only used
for some Hubble-based occultations. May be appropriate for
extremely long duration occultations of a high proper motion
star (e.g., u36). Required in labels of ring occultation
observations. Not intended as a value for a table field.
The sampling_base attribute indicates the
numeric base of the associated logarithmic or exponential
sampling interval.
The sampling_interval_length attribute provides
the spacing of points, in units of length, at which data are
sampled and at which a value for an instrument or data parameter
is available. This sampling interval can be either the original
(raw) sampling or the result of some resampling process.
The sampling_scale attribute indicates the type
of scale that applies to the sample interval increments. It must
have a value of either Linear or Logarithmic.
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.
sigma_projected_star_diameter indicates the
uncertainty (1-sigma) in the projected_star_diameter.
sigma_time_constant indicates the uncertainty in
the time_constant. See Eq. 9 Elliot et al. (1984) Astron. J.
1587-1603. If this attribute is used them the attribute
time_constant also must be present.
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.
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_constant indicates the instrumental time
constant of the detector. See Eq. 9 Elliot et al. (1984) Astron.
J. 1587-1603. If this attribute is used them the attribute
time_constant_type also must be present.
time_constant_type distinguishes between three
types of instrumental time constant assumed in a square-well
model. This attribute is required if the time_constant attribute
is present.
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 used where the occultation
track is not monotonic over relatively short time scales.
Generally only used for some Hubble-based occultations. May be
appropriate for extremely long duration occultations of a high
proper motion star (e.g., u36). Not intended as a value for a
table field.
The vertical_display_axis attribute identifies,
by name, the axis of an Array (or Array subclass) that is
intended to be displayed in the vertical or "line" dimension on
a display device. The value of this attribute must match the
value of one, and only one, axis_name attribute in an Axis_Array
class of the associated Array.
The vertical_display_direction attribute
specifies the direction along the screen of a display device
that data along the vertical axis of an Array is supposed to be
displayed.
wavelength of the observation. Optional in
labels. If the observation is over a wavelength range, use the
corresponding minimum and maximum attributes instead.