Well I meant, how would the galaxy and more specifically, the area around us change from the way it is now.
Re: NGC 6240 Yes. The 'names' come from the catalogues that detected or measured them. The more common ones in use are, M = Messier NGC = New General Catalogue There are though a large number of other cataogues. The Arp peculiar galaxies and the IC catalogue come to mind. The same goes for star naming conventions.
Point: they are 400 million light-years from us. One problem with saying "future" in astromony is that when you get things like this, they've probably already happened, we just haven't seen it yet. We just won't be affected (if at all) for a "few huindred million years."