Tk::Error: Unable to read catalog since no file specified and no default known. at /some/dir/perl/lib/perl5/Astro/Catalog.pm line 842.
 Tk callback for .toplevel1.frame1.menubutton.menu
 Tk::__ANON__ at /some/dir/perl/lib/perl5/x86_64-linux-thread-multi/Tk.pm line 251
 Tk::Menu::Invoke at /some/dir/perl/lib/perl5/x86_64-linux-thread-multi/Tk/Menu.pm line 532
 <ButtonRelease>
 (command bound to event)