Just found an answer that requires an additional step for Mac users but it appears to work! I followed the directions from this site (it's a simple one line Mac Terminal command):
Does this mean that Mac users are going to have to do this dance with the terminal for all subsequent releases? Or is there something that the developers can add to the releases to make them more palatable to Apple?
This 'damaged' message is something that only cropped up over the last 2 or 3 weeks. I understand Jasem is aware of this problem and I would imagine a fix is in the works. I meant this post only as a temporary way to get around not being able to download and run KStars at all in the meantime.
The one positive of this method is that you don't have to go through the Systems Settings/Privacy & Security mess when you download a new version of KStars. This terminal command seems to bypass that.
Fred, no need to go into system settings to open a unknown file on Mac. Just Control-click the app icon, then choose Open from the shortcut menu. Click Open. The app is saved as an exception to your security settings, and you can open it in the future by double-clicking it just as you can any registered app.