More than three decades after activist-artists the Guerrilla Girls first called out New York’s Metropolitan Museum of Art—along with other major US institutions—for showing a paltry percentage of works by female artists, the British sculptor Cornelia Parker gives the thumbs-up to her Transitional Object (PsychoBarn) as it is installed on the Met’s roof. Her eerie addition to the Manhattan skyline is the institution’s first roof-garden commission by a female artist. Even before the museum’s site-specific commissions began, the commanding height overlooking Central Park was mainly the preserve of male artists. Supported by Bloomberg Philanthropies, with additional support from Cynthia Hazen Polsky and Leon B. Polsky, Parker’s Alfred Hitchcock-meets-Edward Hopper work went on show on 19 April (until 31 October, weather permitting).