Sommers-Bausch Observatory is marked with the blue dot. The area just to the left (west) of the city comprises Boulder City Parks, and encompasses the famous Flatirons and several foothills known as Flagstaff, Green, and Bear Mountains.
Travel Tip: Blend In with the Natives
Resident lifeforms known as "boulderites" are fiercely interested in ecological preservation. Thus, alien visitors who are interested in becoming immersed in the native culture without calling undo attention to themselves should consider landing in the fire-damaged foothills area to the southwest of the city. That way, even if you sterilize the earth with your fusion drive, nobody will notice.
Then, make your way into Boulder via The Hill (just west of campus) .... which still retains a bit of its old-world charm and reputation as the Haight-Ashbury of the Midwest. There, you should easily be able to blend in completely unnoticed ... or at worst, simply be mistaken for just another student riot.