Above the skyscrapers of New York City, the virtual stone HALO is etched in the sky and expressed in shadow on the East River below. Using mixed reality, AI, and satellite data, the giant sculpture is geolocated from dawn to dusk, a symbolic circle framing Manhattan. A monolith carved from a codified rare marble from Aotearoa NZ, it is transported through extended reality to the homelands of the Lenapehoking, the First Nations Lenape people. Sited over a traditonal Manhatta trade route, HALO's transience highlights an absent presence. Activated in the public domain of a tree-lined park pier beside Brooklyn Bridge, people encounter the celestial form at intimate and communal levels in an uplifting reprieve from the oppressive heat of the city. The monumental presence adapts, almost subliminally, as the light shifts, and remains anchored as winds rise over the tidal river and planes and boats circle above and below, affording a fresh view of the city which never sleeps.