Enjoy a Halloween party for adults 21 and older (valid ID required for entry). Bust some scary moves with DJ-led music in the atrium and hits from the 70s in the Disco Cave. At 8 and 8:45 p.m., fear the frightening fractal shows in the planetarium for $5. Also for $5, try to survive seeing “Nightmare on Elm Street” on the giant DynaTheater screen, starting at 9 p.m. Devilishly delicious food and goodies will be available along with a cash bar. The evening comes to a cryptic conclusion with a costume contest and prizes for the most frightening outfit.