UCD Maintenance Standard/ Proposed Recommendation: Request for Comments

The Maintenance Process for the set of terms defined as IVOA Unified Content Descriptors is defined in this specification in order to allow the UCD list to evolve following the needs of the astronomical community.

  • the web pages where to propose new terms to be included
  • the review process
Latest version of Maintenance For UCDList can be found at:

Reference Interoperable Implementations

The process is illustrated by the modification request page and the various update, comment, and validation steps registred directly on the page.

Actors in the process are : IVOA participants , Semantics Working group chair and vice-chair, UCD maintenance board committee .

Implementations Validators

Illustration for the add-ons of new terms related to Planetary science . / B. Cecconni , S. Erard

see for instance the RFM Page : UCDList_1-4_RFM

Comments from the IVOA Community during RFC/TCG review period: 2018/09/12 - 2018/10/12

The comments from the TCG members during the RFC/TCG review should be included in the next section.

In order to add a comment to the document, please edit this page and add your comment to the list below in the format used for the example (include your Wiki Name so that authors can contact you for further information). When the author(s) of the document have considered the comment, they will provide a response after the comment.

Additional discussion about any of the comments or responses can be conducted on the WG mailing list. However, please be sure to enter your initial comments here for full consideration in any future revisions of this document

Comments from TCG member during the RFC/TCG Review Period: 2018/10/26 - 2018/11/16

WG chairs or vice chairs must read the Document, provide comments if any (including on topics not directly linked to the Group matters) or indicate that they have no comment.

IG chairs or vice chairs are also encouraged to do the same, althought their inputs are not compulsory.

TCG Chair & Vice Chair

Applications Working Group

I approve the document.

While reading, I did have the same questions and concerns raised by DM and GWS, so I endorse their suggested changes and clarifications.

-- TomDonaldson - 2019-03-22

Data Access Layer Working Group

DAL chair/vice approve the document.

However there are a couple of points we'd like to see clarified or acted upon.

One (major) is about the ucd-sci@ivoa.net mailing list. The list seems to be outdated and, while it is asked the submitters to send notification of requests there, this is not reflected in the RFM page.

A second (medium) is about the "user" role, described as "any member of the astronomical community" on page 3, but later the doc states any "IVOA member". Given IVOA membership is not so well defined...maybe saying "anyone who has successfully obtained an IVOA TWiki account" would do and would solve also the contact information needed.

Other minor/typographical things are:

  • page 3: Introduction - "...as described in [3]", maybe it's better to explicit the DocStdProc because it's the first time it is referred to.
changed MLouys 20190520
  • page 5: could "clarification" inside "amendment" be a separate bullet (or sub-bullet)?
added MLouys 20190520
  • page 6: reference to [1] towards the end of the page looks like it should be reference to [3]
changed MLouys 20190520
  • page 5: 2.2 - "list is approved as Endorsed Note" -> "list is approved as an Endorsed Note"
changed MLouys 20190520
  • global: the document does not have page numbers or any header/footer
changed MLouys 20190520 We support also the DM request for cleaning the TWiki topic naming syntax. Naming of RFM pages :Fixed during Interop May 2019 thanks to Marco Molinaro MLouys 20190520

-- MarcoMolinaro - 2019-04-15

Data Model Working Group

The document is clear and straight forward.. no problem there.

My only comment is that the implementations (last 2 cycles of RFM) do not follow this procedure, at least with respect to the naming convention for the twiki pages. The spec says "UCDlist-<version_number>-<date>-RFM" while the 2 most recent are "UCDList1dot42017June2018FebRFM" and the current is "RFMforUCD".

Also, can you clarify for me, the <version_number> is the version of the released UCD list. For example, the current REC is 1.3, so the list being built up as RFM to that list should be in a file named "UCDlist-1_3-<date>-RFM", and the 1.4 list (above) would be updates to a V1.4 Endorsed Note, which does not seem to exist. Do I have this right?

I will approve the document, but would like to see these cleaned up to make it clearer for following the procedure in the future.

  • Changes: renaming, redirections to keep existing names (the ones above) and alignment of version numbers, removing the date element have been made. Now the 2 topics above figure out as UCDList_1-3_RFM & UCDList_1-4_RFM. -- MarcoMolinaro - 2019-05-16

Grid & Web Services Working Group

The process seems reasonable and straightforward. I only have a couple of document formatting requests:

  • In the PDF version, the title is prefixed with "Microsoft Word - ". Can this be removed?
changed MLouys 20190520
  • In the PDF version, many of the blue underlined words that seem like they should be links but are not. I suggest enabling the links or removing the blue and underscores.
-- BrianMajor - 2019-03-12 _Changed as Links _ M.Louys 20190520

Registry Working Group

I approve of this document. I see the scientific advisory board to Semantics functioning as a less meeting-involved arm of the working group, much as registry maintainers in the RofR ecosystem are often indirectly involved in meetings but necessary for our WG's reference implementations and feedback. Hopefully the change to Endorsed Notes also helps speed up process.

One grammar comment for the introduction: Singular "they" would be more natural in English here and more inclusive, over "he/she". -- TheresaDower - 2018-10-29 _adopted the singular "They" for inclusive notation, thanks _ MLouys 20190520

Semantics Working Group

Data Curation & Preservation Interest Group

Education Interest Group

Knowledge Discovery in Databases Interest Group

Solar System Interest Group

Theory Interest Group

Time Domain Interest Group


Standards and Processes Committee

TCG Vote : Vote_start_date - Vote_end_date

If you have minor comments (typos) on the last version of the document please indicate it in the Comments column of the table and post them in the TCG comments section above with the date.

Group Yes No Abstain Comments
Apps *      
DAL *     the mailing list should be updated, enforced and reflected in the RFM pages
DM *     would like to see the implementations cleaned up to make following the procedure easier in the future
GWS *     Minor formatting changes requested.

Topic revision: r12 - 2019-05-20 - MireilleLouys
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