Occultation Profiles
Four new volume sets have been added to OPUS, all containing occultation profiles of Saturn's rings:
- CORSS_8001 (197 from Cassini RSS)
- COUVIS_8001 (277 from Cassini UVIS)
- COVIMS_8001 (248 from Cassini VIMS)
- EBROCC_0001 (12 from ground-based telescopes)
To support these, there is a new Observation Type called Occultation Profile and a new Occultation Constraints section on the left side of the main Search tab:
The available search fields are:
- Occultation Type - The type of the occultation (Radio, Solar, or Stellar)
- Occultation Direction - The direction of the occultation through the ring plane (Ingress, Egress, or Both)
- Body Occultation Flag - Yes or No indicating if there is a planetary or satellite body intercepted by the profile
- Temporal Sampling Interval - The time interval between adjacent points in the profile
- Data Quality Score - For data sets that support it, the subjective quality of the profile (Good, Fair, or Poor)
- Detectable Optical Depth - The range of optical depths detectable in the profile
- Wavelength Band - The wavelength of the observation (S, X, Ka, IR, Visible, or UV)
- Signal Source Name - The source of the photons used in the profile (Cassini or the name of a star)
- Receiver Host Name - The name of the receiver (Cassini, a DSN antenna, or one of the ground-based telescopes)
For the occultations currently available, the Intended Target Name is always Saturn Rings. For the ground-based occultations, the Mission is Ground-based and the Instrument Name is the name of the ground-based telescope.
Other search fields relevant to occultations can be found in other categories:
- Wavelength Constraints includes information on the actual wavelengths used to create the profile
- Ring Geometry Constraints includes information about incidence, emission, and ring opening angle, ring radius range, ring longitude range, and ring resolution
- Cassini Mission Constraints, Cassini UVIS Constraints, and Cassini VIMS Constraints, as appropriate, include information about the raw observations that were used to make the profile
Most occultation profiles are available in multiple resolutions. All of these versions are combined together into a single OPUS observation. Which resolution(s) you want to actually download can be selected on the Cart tab:
Note that there are no thumbnail preview images for occultation profiles at this time (but we hope to generate them soon), so we suggest you browse your search results in the Table View.
Other Miscellaneous Changes
We implemented a few other minor interface changes and bug fixes in the metadata in this release that will probably be invisible to most users, but are listed here for completeness:
- Selections that are not relevant are now called "N/A" instead of "NULL".
- We changed all Ring Geometry Constraints "body center" metadata fields into "range" fields (with a minimum and maximum stored in the database) to support the ranges available for occultation profiles. These fields now support the "any/all/only" query types, although for non-occultation observations the minimum and maximum will always be the same for a given observation. In the future, all ring geometry will be regenerated so that these fields have appropriate ranges of values.
- The Surface Geometry Constraints / Multiple Target List metadata field is now in title case instead of all upper case.
- We fixed a problem with Cassini UVIS HSP observations where they had the wrong duration and stop time.
- We changed Cassini VIMS IR and Visual exposure durations to be in units of seconds instead of milliseconds to be consistent with all other duration fields
As always, we hope you and yours are safe during these trying times, and we look forward to hearing your comments, questions, and suggestions.
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