Would be kind of rude to FORCE people to stop everything; if even for an hour, don't you think? Sure, I'm completely fine with encouraging it but some people have important things they're doing; from a University senior that's wrapping up his thesis, to a troubled young couple that's finally discussing things, to that woman fighting for her job. It's kind of rude to think people just don't have anything to do; if even for an hour.
I think something like this would help create more respect and closeness for nature, and I think thats important, more so than a couple having 'the talk', or some dissertation. Obviously there would be issues like running hospitals, street lighting for necessary travel and ofcourse some people wont care for it.
At the end of it we're all dead anyway, what a shame if you died never having seen the starry sky and real darnkess, moonlight, quietness etc.