Comment by news_to_me

There's also a lot less visible sky in a lot of places in a city—it only takes four or five stories to limit your view and block the moon a lot of the time. And in my experience, it's less the brightness of lights than the sheer volume of light from a city that reduces the apparent brightness of the moon and stars. I'm always amazed how you can see the halo of a city over the horizon at night just from its lights.