NASA astronauts Sunita 'Suni' Williams and Barry 'Butch' Wilmore will pilot the first crewed mission of Boeing's CST-100 Starliner, marking a significant milestone in American spaceflight.

The mission will take place aboard the 100th launch of United Launch Alliance's Atlas V rocket - its first dedicated to human spaceflight - with a 95% chance of favorable conditions for the 10:34 p.m. ET liftoff from Florida.

The Starliner's inaugural astronaut mission will involve a weeklong stay at the International Space Station, with the goal of thoroughly testing the spacecraft's systems before regular service commences.

Success of this mission is poised to end NASA's dependence on Russian spacecraft for ISS crew transport, potentially lowering the cost of space travel and enhancing U.S. space autonomy.

Boeing has committed to six missions with the Starliner and is exploring the option of adding a fifth seat for private customers, signaling a broader shift towards commercialization in space services.