Not quite sure how you're suppose to celebrate this---kiss an astronomer I guess.
I'm not a stargazing type person myself. Mocha-momma gets rather irritated with me at times due to my lack of excitement about looking at the moon. I don't know how many times she's said to me, "come look at the moon, it's beautiful." My response is generally something along the lines of, "yep, it's still up there." I guess the thing is that not only am I suppose to take time to stop and smell the roses, I'm also suppose to take time to gaze in wonder and stare at the moon.
Anyway, if you want to find out what's going on in MN re: astronomy day activities, you can go to the web site for the Minnesota Astronomical Society. Click on the banner. It would seem there are a whopping 450 members of this organization who would just love for you to join them. (they probably could use the dues)