CASA measures library

 The casacore package contains the core libraries of the old
 AIPS++/CASA (Common Astronomy Software Applications) package. This
 split was made to get a better separation of core libraries and
 applications.
 .
 This package implements measures (i.e. quantities with references frames) and
 their persistency. Examples are the Hour-angle and Declination of a source at
 a certain time and observatory; an Ra/Dec for a certain mean epoch; an
 apparent frequency at a certain time given in eV; a local sidereal time at an
 observatory. Measures can be converted from one reference frame to another
 (and this possibility is its main reason for existence).