Quasar classification (in Re: WD-Ontology)

[Kjetil Kjernsmo]

On Wednesday 21 February 2007 16:22, Andrea Preite Martinez wrote:
> QuasiStellarObject

Sorry to be bursting in from the sideline here. :-) I have not worked in 
astrophysics for a few years (rather worked with the Semantic Web), but 
I was confused about both the chosen name and the RDF that follows it. 
I don't know if it is appropriate to address my concerns in this forum, 
or if it has been decided elsewhere, but here goes:

I have been of the impression, especially from Julian H. Krolik's 
excellent text book on Active Galactic Nuclei, that the AGN community 
now prefers to "forget" that there ever was anything "stellar" in 
quasars. Allthough it has great historical significance, it now only 
serves to confuse people. I think that the community generally 
recommends that "quasar" is adopted as a new word, and that if one 
wants to distinguish different kinds of quasars by their radio 
properties, they should be called "radio-quiet" and "radio-loud". 

Quasars are clearly Active Galactic Nuclei, however, and so the RDF/XML 
OWL fragment confused me even more: 
  <owl:Class rdf:ID="QuasiStellarObject">
    <owl:disjointWith>
      <owl:Class rdf:about="#ActiveGalaxyNucleus"/>
    </owl:disjointWith>
  <owl:Class>

I'd rather say that:
  <owl:Class rdf:ID="QuasiStellarObject">
    <rdfs:subClassOf>
      <owl:Class rdf:about="#ActiveGalaxyNucleus"/>
    </rdfs:subClassOf>
  <owl:Class>

and if using the terms I think the AGN community would prefer, 
  <owl:Class rdf:ID="Quasar">
    <rdfs:subClassOf>
      <owl:Class rdf:about="#ActiveGalaxyNucleus"/>
    </rdfs:subClassOf>
  <owl:Class>

I hope that this input is useful and that mine or other's confusion can 
be cleared up.

Best,

Kjetil
-- 
Kjetil Kjernsmo
Programmer / Astrophysicist / Ski-orienteer / Orienteer / Mountaineer
kjetil at kjernsmo.net
Homepage: http://www.kjetil.kjernsmo.net/     OpenPGP KeyID: 6A6A0BBC