NEW ORLEANS (AP) — A massive structure described by NASA as the world’s largest spacecraft welding tool has been completed at the Michoud (MEE’-shoo) Assembly Center in New Orleans, which was chosen in 2011 to build components of a major new rocket system.

The 170-foot-tall, 78-foot-wide structure is called the Vertical Assembly Center. It will play a key role in construction of “Space Launch System” rockets.