Trimble Planning (the windows exe) remains the one tool that works to plan the GNSS day, but its a bit old in the tooth. There was a time when the online GNSS planning tool (from Ashtech) use to work, but its likely not written in HTML5 or some other modern language, which forces one to install silverlight which is long past deprecation for a utility to run in Chrome, IE etc.
Can your team please uprade the ONLINE GNSS Planning tool? As a mapping CT, it would make students more aware of what is going on above them in a class setting if folks could be pointed simply to a URL and observe the sky. GNSS planning tool worked great when it worked.