Washington, Sep 13 (IANS): NASA has unveiled the largest spacecraft welding tool - the Vertical Assembly Center (VAC) - at its Michoud Assembly Facility in New Orleans.

The 170-feet-tall, 78-feet-wide giant VAC completes a world class welding tool kit that will be used to build the core stage of America's next great rocket - the Space Launch System (SLS), the US space agency said in a statement.

VAC is part of a family of state-of-the-art tools designed to weld the core stage of SLS and will join domes, rings and barrels to complete the tanks or dry structure assemblies.

It will also be used to perform evaluations on the completed welds. Boeing is the prime contractor for the SLS core stage, including avionics.

"This rocket is a game changer in terms of deep space exploration and will launch NASA astronauts to investigate asteroids and explore the surface of Mars while opening new possibilities for science missions as well," said NASA administrator Charles Bolden.

NASA engineers are working on several additional welding tools and recently they completed welding all the rings for the first flight of SLS.

The rings connect and provide stiffness between domes and barrels, which will make up the five major core stage structures: the forward skirt, the liquid oxygen tank, the intertank, the liquid hydrogen tank and the engine section.

SLS will be the world's most powerful rocket for deep space missions.