Common Astronomy Software Applications

CASA, the Common Astronomy Software Applications, is the primary data processing software for the Atacama Large Millimeter/submillimeter Array (ALMA) and Karl G. Jansky Very Large Array (VLA), and is often used also for other radio telescopes.

6.5.0 Release

CASA 6.5.0 can now be downloaded for general use. CASA 6.5.0 is available either as a downloadable tar-file, or through pip-wheel installation, which gives flexibility to integrate CASA into a customized Python environment.


  • imbaseline: a new task imbaseline was added for image-based baseline subtraction for single-dish data.

  • corrbit(): a new method corrbit() was implemented in the msmetadata tool for returning the value in SPECTRAL_WINDOW:: SDM_CORR_BIT column.

  • setjy: the parameter ‘modimage’ was removed and parameter ‘model’ should be used instead.

  • plotms: support was added for additional axes of calibration tables.

  • tclean: the return dictionary now includes additional information about the minor cycles.

  • Mac OS 12: a bug was fixed which prevented the Mac OS 11 / Python 3.6 package to open on Mac OS 12.

For more details on these and other new features, see the CASA 6.5.0 Release Notes.

CASA is developed by an international consortium of scientists based at the National Radio Astronomical Observatory (NRAO), the European Southern Observatory (ESO), the National Astronomical Observatory of Japan (NAOJ), the Academia Sinica Institute of Astronomy and Astrophysics (ASIAA), CSIRO Astronomy and Space Science (CSIRO/CASS), and the Netherlands Institute for Radio Astronomy (ASTRON), under the guidance of NRAO.