Restoring and Archiving Voyager 1 Cruise Images of Uranus and Neptune (RAV1CIUN) Peer Review

Oct 2, 2023 — Nov 10, 2023

The Restoring and Archiving Voyager 1 Cruise Images of Uranus and Neptune (RAV1CIUN) archive was created under a PDART task to reprocess all the Voyager 1 cruise images of Neptune and Uranus.  This was accomplished by reprocessing the original legacy (unlabelled) Voyager Imaging Science Subsystem (ISS) data within the PDS using the best available calibrations and analyzing the results to derive planetary reflectance for each phase angle in each Voyager imaging spectral band.  The final, complete results are presented here for peer review.  Additionally, labeled versions of all available images from both Voyager 1 and 2 are provided without further analysis.

The goals of this Peer Review, as with any PR, are to ensure that:

• The data are scientifically useful
• The metadata correctly and comprehensively describes the data
• The supporting documentation is complete and accurate
• The archive wholly complies with PDS4 standards

Not all review members are expected to comment on all of the above objectives.  The group, as a whole, will accomplish this.

Ultimately, your review of this bundle will consist of a written set of comments, clarifications, and discrepancies that, if implemented and/or corrected, would improve the archive.  These written statements need to be provided to the Review Coordinator(s) by the "Comments Due" date in the Schedule.  Please refer to the Providing comments section for more information about how your comments can be delivered, collated and adjudicated.

GETTING STARTED

The VGR archive bundle can be viewed in a hierarchical fashion here:

https://planetarydata.jpl.nasa.gov/data/reviews/c99735f782e66f80411439e71075b67f/wenkert_pdart16_vgr_rav1ciun/

Bundle organization

Within this bundle, there are seven collections — effectively subdirectories focused upon specific types of data and their commensurate metadata.

To navigate the science data, go to the judiciously named data/ collection, and drill down through the various subdirectories to find products of interest.  The PDS4 XML labels can be viewed directly in most Web browsers.

NOTE: This peer review bundle is the entirety of the data being submitted for the PDS archive.  The ability to reprocess the complete data set and/or entertain large changes will be quite limited and doing so may not be possible.

The browse/ collection contains viewable image representations of the corresponding products in the data/ collection.  Generally, web browsers can directly display these images.  

The calibration/ collection contains the full set of calibration, lookup tables and parameter files used to process the VGR data for this bundle.

The data_csv/ collection contains all of the non-image data for the bundle. Most are Derived data.

The document/ collection contains several artifacts that, together, document both the VGR data and its pedigree with the.

The miscellaneous/ collection contains the Velocity templates used to create the detached PDS4-compliant metadata labels from the original attached VICAR/ODL labels found within each of the data artifacts

Lastly, the scripts/ collection contains scripts demonstrating and documenting the processing flow that created these data; the processing for creating this archive bundle in a PDS4-compliant manner; and performing various analysis operations.

Orienting yourself

If you want to just look at the high-level results, see the "final_statistics" files described in sections 3.5.1 to 3.5.3 of the SIS, and the "planet_albedo" files described in 3.5.4.

The derivation of these products are in the "RDR" products described in sections 3.2 to 3.4.

If you are interested in the rest of the Voyager data set should look at the QEDRs described in section 3.1.  Note the "catalog.csv" file in the data_csv collection, which contains a large amount of metadata about the images and can be used to find images of interest.

Those interested in reproducing the results should look at the scripts outlined in section 3.6.

The first thing to look at is probably the Software Interface Specification, or SIS, found here:

https://planetarydata.jpl.nasa.gov/data/reviews/c99735f782e66f80411439e71075b67f/wenkert_pdart16_vgr_rav1ciun/document/VGR_RAV1CIUN_SIS.pdf

Providing comments

Reviewers are welcome to provide comments in any preferred format via email to the Review Coordinators. The Google Sheet linked below is available for your use, but is not required (each reviewer has a named tab within this Sheet for their own use).

https://docs.google.com/spreadsheets/d/1dZVyyshujMAyvbEsWsumhB3Z6hkInL_He7KGuGHti_Q/edit#gid=0

This sheet will ultimately be used to adjudicate reviewer comments and convey the Data Provider’s response to each of these comments.  So, however review comments are delivered to the Review Coordinators, they will be distilled and tracked here.

DATA ACCESS

Overview of access/interaction methods:

1. Possible interactive methods for perusing the imaging archive:

1. Directly interacting with this web site: you can simply go spelunking through the archive structures by clicking on the links.  This method is useful for deciphering the archive bundle structure.  It may also be the simplest way to examine the PDS4 labels.  
2. Browse image collections: the archive bundle includes a browse collection that contains representations of the data in easily rendered formats.  This may be more convenient than interacting with the delivered VICAR/ODL formatted data.  As these are PNG formatted images, any standard viewer should work.
3. Use the xvd image viewer client: xvd is the VICAR image display program.  It can easily view the native VICAR/ODL products found in the data/ collection once you download them to your computer.  xvd is available as part of the VICAR Open Source release, which can be found here:

https://www-mipl.jpl.nasa.gov/vicar_open.html

There is a Docker version available that should let you run xvd on any computer (particularly Windows, as it does not run natively on Windows).

For Linux or Mac, you can run xvd natively.

LIENS/ERRATA/NOTES/COMMENTS

There are a handful of issues with the bundle as you see here for this review:

1. Some PDF documents are known to not validate as PDF/A.  We know this to be the case for Benesh_Jepsen_1978.pdf.  This will be corrected before the revised bundle is publicly released.
2. The Velocity templates (in the miscellaneous collection) are missing some last-minute changes to fix validation errors.  They will be updated in the final bundle.
3. The VGR2 QEDRs have known errors in the SCET epochs 2-4, which also causes issues with the mission_phase_name.  This is simply a label conversion problem and thus should be fixable, and we hope to be able to address that after the Peer Review. We are waiting in case there are other label fixes.  VGR1 QEDRs do not have this issue.

SCHEDULE

REVIEWERS