This vocabulary is based on a set of keywords maintained jointly by the
publishers of the journals Astronomy and Astrophysics
(A&A), Monthly Notices of the Royal Astronomical Society
(MNRAS) and the Astrophysical Journal (ApJ), and updated on
an annual basis. The different
journals are slightly inconsistent with each other; we have rather
arbitrarily used the 2008 list from the A&A web site. The intended
usage of the vocabulary is to tag articles with descriptive keywords
to aid searching for articles on a particular topic.
The keywords are organised into categories which have been modelled as
hierarchical relationships.
Additionally, some of the keywords are grouped into collections which
has been mirrored in the SKOS version.
The vocabulary contains no definitions or related links as these are
not provided in the original keyword list, and only a handful of
alternative labels and scope notes that are present in the original
keyword list.