OpenNGC is a database containing positions and main data of NGC (New
General Catalogue) and IC (Index Catalogue) objects. It has been built
by merging data from NED, HyperLEDA, SIMBAD, and several databases
available at HEASARC.
In this VO publication, we have changed most of the column names,
mostly to make them work as ADQL column names without resorting to
delimited identifiers. The mapping should be obvious.
