I can't say I went there to go spotting, but I did go to see the airport. Or should I say intergalactic spaceport?
This is the Greater Green River Intergalactic Spaceport (yes, that's its name):
It was, apparently, created in 1994 when, in response to NASA stating that Jupiter would be hit by several comets and meteors, the citizens of Green River, Wyoming, decided that the Jovians might want a place to evacuate to before things got ugly.
So far, unsurprisingly, no Jovians have landed there. One would think that if that they happened to show up and discovered that this is what was set up for them, they might decide to try their luck on a different planet.
It does, however, remain open to whatever air traffic wants to land there (and is willing to brave the runway): http://www.airnav.com/airport/48U