Installing CASA on Mac OS


CASA for Macintosh is distributed as self-contained Macintosh application. For installation purposes, this means that you can install CASA by simply dragging the application to your hard disk. It should be as easy as copying a file.
  1. Download the CASA disk image for your OS version from our download site
  2. Open the disk image file (if your browser does not do so automatically).
  3. Drag the CASA application to the Applications folder of your hard disk.
  4. Eject the CASA disk image.
  5. Double-click the CASA application to run it for the first time. If the OS does not allow you to install apps from non-Apple sources, please Change the settings in "System Preferences-> Security & Privacy -> General" and "Allow applications downloaded from: Mac App store and identified developers".
  6. Optional: Create symbolic links to the CASA version and its executables (Administrator privileges are required), which will allow you to run casa, casaviewer, casaplotms, etc. from any terminal command line. To do so, run !create-symlinks from a CASA prompt.
  7. Optional: To update the data repository, run !update-data from the CASA prompt.

Multiple installations of CASA

If you want to have more than a single version of CASA in the Application folder, simply rename the to some other name (e.g. When you double click on any available version, that specific one will be launched. And if you recreate the symbolic links as explained above, the casa, casaviewer, casaplotms, etc. executables will then be pointing to that version. Switching CASA versions then comes down to double click the wanted Application and recreate the symbolic links if desired.



If you encounter difficulties, please see our list of known problems or consult the CASA helpdesk or ALMA helpdesk, where we maintain knowledgebase articles and where you can get in touch with us. You may also consult the NRAO Science Forums to discuss any CASA issues amongst CASA users.

If you want to be kept up to date about CASA, please subscribe to our CASA mailing lists.

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