Next Door in Chinatown hosts its monthly Camera Obscura party Saturday, presided over by KTUH college radio/promoter DJ Nocturna. Guests are invited to dress in theme as their favorite science-fiction character, alien or unidentified outer-space being and dance to the dark '80s, gothic and electro beats of Nocturna, Politix and Kyoko, 9 p.m. Saturday, NextDoor, 43 N. Hotel St., $10; 548-6398, www.myspace.com/djnocturna.