What is the approximate measured length of the Milky Way's central bar structure?

20,000 light-years long

Observations derived from mapping efforts, particularly infrared surveys focused on penetrating the core region, strongly suggest the presence of a bar-shaped structure running through the center of the Milky Way. This bar is comprised mainly of older stars. The measurement consistently inferred for the physical extent of this central bar is approximately 20,000 light-years in length. This finding is a crucial part of the accepted barred spiral model, as it dictates where the prominent spiral arms appear to originate, sprouting outward from the ends of this central bar rather than directly from the very center.