VEP-017: refframe#geo_app

[Baptiste Cecconi]

I am fine with this proposal.

Baptiste

> Le 20 nov. 2024 à 15:02, Markus Demleitner via apps <apps at ivoa.net> a écrit :
> 
> Dear Semantics, Apps, and DM WGs,
> 
> In our refframe vocabulary, we have a term geo_app that we have
> inherited from VOTable's COOSYS/@system.  When we created the
> vocabulary, nobody could quite remember what it was supposed to mean,
> in particular because the "geo" part made us suspect it would have
> been a frame for Earth.
> 
> At the recent Interop, JJ Kavelaars recognised what this was supposed
> to mean: geocentric apparent positions.  Even though the term is
> deprecated (and we will not un-deprecate it for reasons mentioned
> below), we should fix the ugly label and description.  This is what
> VEP-017 tries:
> 
>  Vocabulary: http://www.ivoa.net/rdf/refframe
>  Author: Markus Demleitner <msdemlei at ari.uni-heidelberg.de> and J.J. Kavelaars
>  Date: 2024-11-17
> 
>  New Term: geo_app
>  Action: Modification
>  Label: Geocentric Apparent Positions
>  Description: Positions given as observed by a fictitious observer at the
> 	  Earth’ s centre for the equator of observation.
>  Relationships: narrower than #EQUATORIAL
>  Used-in: VOTable legacy
> 
>  Rationale:
>  When the legacy VOTable terms were added to the refframe vocabulary
>  (which was necessary to keep validity criteria when VOTable changed
>  COOSYS/@system to being controlled by this vocabulary), nobody rememberd
>  what geo_app might have meant.  It recently turned out that it must
>  have been “Geocentric Apparent”, a frame used primarly in geodesy and
>  solar system science.  It is documented to some extent in
>  https://starlink.eao.hawaii.edu/docs/sun211.htx/sun211ss454.html.
> 
>  This VEP replaces label, description, and relationship for the concept.
>  At this point, this is a deprecated concept, and since it is mixing
>  refposition and frame ("geocentre" vs. "apparent positions at equator of
>  epoch"), we quite certainly won't want anyone to use it.  We still want
>  to update the concept metadata and hence ask for exemption from the
>  “must be used somewhere” rule.
> 
> https://github.com/ivoa-std/VEPs/blob/d79185c3a36bf704b84fe439ba4513b8cfb5304e/VEP-017.txt
> 
> Comments?  Thoughts?  I'd say this is reasonably harmless, and so I'd
> suggest to bring this to the TCG in about two weeks if nobody
> protests here.
> 
> Thanks,
> 
>             Markus
>