At 238,000 SF, the Physics and Astronomy Building is the largest single structure on Johns Hopkins University’s Homewood campus. Teaching and research areas are joined by a 4-story rotunda, and capped by an observatory. The research facility has 36 labs and 200 faculty offices. The labs’ structural and mechanical designs are fully interdependent. Special spaces include remote observatory control rooms, clean rooms, high bay areas, x-ray, vibration isolation, machine shops, computer centers, a 330-seat auditorium, library, and classrooms.