University of Washington Planetarium, Physics-Astronomy Building, 3910 15th Ave NE, Room C319, Seattle WA 98195. The UW Seattle Planetarium features a 30-foot diameter fully digital dome for an interactive and immersive planetarium experience. Public shows are usually offered on the first Friday of each month during the academic year (September-May). Shows are free, but you must reserve tickets in advance for these shows due to the limited capacity of the planetarium. The ticketing link is usually posted on the UW Planetarium Facebook page or UW Planetarium Eventbrite page, usually the Sunday preceding the first Friday of the month.