New post

Why Are Duplicate Copies Of PGC Galaxy And GAIA Star Databases Installed On macOS? (Answer: Apple Makes Us Do It This Way)

I just discovered that somehow duplicate complete copies of the Gaia star and PGC galaxy extension databases were installed when I downloaded them in SkySafari Pro 6 back in 2018. The first set is in:

/Library/Application Support/AppStoreContent/com.simulationcurriculum.SkySafari6MacPro/Products/com.simulationcurriculum.SkySafari6MacPro.UCAC5Extension/Contents/GAIAStars2.skydat

/Library/Application Support/AppStoreContent/com.simulationcurriculum.SkySafari6MacPro/Products/com.simulationcurriculum.SkySafari6MacPro.PGCExtension/Contents/PGCGalaxies2.skydat

and the second set is in:

/Users/marklowenthal/Library/Containers/com.simulationcurriculum.SkySafari6MacPro/Data/Library/Application Support/SkySafari 6 Pro//GAIAStars2.skydat

/Users/marklowenthal/Library/Containers/com.simulationcurriculum.SkySafari6MacPro/Data/Library/Application Support/SkySafari 6 Pro//PGCGalaxies2.skydat

Each set is 1.8GB, a not insignificant chunk of disk space. The files have extactly the same sizes and creation time and dates. Do I need both of these? If not, why wasn't the unneeded one automatically purged? Can I delete one of the sets to reclaim some disk space?

Both PGCGalaxies2.skydat files are dated Mar 21, 2018 12:47pm and both GAIAStars2.skydat files are dated Oct 18, 2018 2:48pm.


1 comment

  • 0
    Bill Tschumy

    We are aware that 2 copies are left after the download.  It is the second set that we actually use.  

    We do make a programmatic call to delete the first copy but the file permissions are such that most users don't have permission to delete it.  Apple doesn't provide any guidance for what to do here.  I assume they think most downloads are not so large and leaving an extra copy is not a big deal.

    You can attempt deleting the first set using the Finder or the command line in Terminal.  If you are using the Terminal you will probably have to sudo the rm command to remove it as root.

Please sign in to leave a comment.