This young, Bavarian-born artist's Coma Sculptor, a pale galactic installation of wood, metal, neon, and light bulbs hovering above a circular black-hole carpet, may be the most expansive and satisfying new thing around. Despite an elegant equilibrium, its intersecting wobbly orbits and black-light bulbs suggest an unstable supercluster on the verge of imploding. Erudite, makeshift, and suave, it's got humor too: Ensconced at the center, at its nucleus, is a sad sausage in a jar. The rococo-cubistic totems in vitrines in the back gallery are metaphors of our own solar system: Mercury has silver cowboy boots, Mars contains five bottles of red liquid, and Venus includes a fur muff being ruffled by a fan. Dahlem calls them "birdhouses for our neighboring planets."