Each year, the Metropolitan Museum of Art cues in the spring season with its annual rooftop commission—a site-specific artwork, with sweeping views of Central Park and the city beyond as its backdrop. This year’s installation, by Berlin-based artist Alicja Kwade, brings an otherworldly element to the popular warm weather attraction with two steel-and-stone sculptures that evoke a miniature solar system.

Titled ParaPivot I and II, respectively, each piece consists of multiple rectangular, powder-coated steel frames that intersect at oblique angles; nine stone spheres—some of which measure more than three feet in diameter and weigh over a ton—resemble planets resting placidly in between the frames or at their corners. The structures, which invite people to walk through and around them, stretch out around several axis points, suggesting the globes’ orbital pathways.