Not interstellar, but I leave near Sunspot, New Mexico. Since lots of schools visit the sunspot observatory there they have a series of signs starting with Neptune at the beginning of the road (Highway 6563 for those interested) and ending with the sun at the observatory. The signs are spaced proportionally over the 15 mile road and it amazing how close mars -> sun all are compared to the rest, and that doesn't even deal with the rest proxima centauri (I'm curious where that would actually be, Colorado?)