Tomás Saraceno: Cloud-Specific Working at the impossible intersection of pragmatism and practicality, Argentinean-born, Frankfurt-based artist and architect Tomás Saraceno creates prototypes for a future city in the sky, a buoyant cloud of molecule-like modules amiably drifting above the overburdened environs below. In this installation Saraceno presents a massive aluminum framework encasing a similarly massive clear-plastic bubble. Viewers are invited to climb inside (after divesting themselves of shoes, rings, keys — anything that might pop Saraceno's balloon), lie on their backs and admire the silver solar cookers affixed to the capsule's upper regions or peruse one of Saraceno's source texts: The Cloudspotter's Guide, Biology of Spiders and R. Buckminster Fuller's seminal essay Operating Manual for Spaceship Earth. The reclining visitor may also take in the view of the gallery outside Saraceno's One Cloud Module: a cluster of iridescent bubbles that resemble Gothic stained glass, bound in black webbing and elastic ropes; a massive mural depicting a model cloud city, with our digitally rendered descendants in their modules, going about their daily tasks; a video projected on another wall that shows Saraceno and a team of collaborators attempting to send aloft his tessellated objects in the manner of NASA test flights. At once whimsical, revolutionary and nostalgic, the work hovers between the absurdly cerebral and the elementally alluring. It's hard not to succumb to the artist's ambitious vision while you're lying on a cloud and contemplating the sky. Through January 9, 2012, at the Mildred Lane Kemper Art Museum, Forsyth and Skinker boulevards (on the campus of Washington University); 314-935-4523 or www.kemperartmuseum.wustl.edu. Hours: 11 a.m.-6 p.m. daily (closed Tue., open till 8 p.m. Fri.).