This code opens Calendar.app to the day of an date-type attribute.
You may need to change the locale to your locale.
// Open date in Calendar.app //
var theDate=$MyDate.format("W, d MM y");
var theAppleScript='tell application "Calendar" to view calendar at date "'+theDate+'"';
var theShellCommand="osascript -e '"+theAppleScript+"'";
(Not sure whether the format dot operator needs to be adjusted. I guess AppleScript uses the same format in every language. If you need to change it see @mwra’s Date Formats)