After nearly four years of playing catchup, Boeing is finally set to join SpaceX as one of two commercial partners capable of flying NASA astronauts to the International Space Station.

Boeing's CST-100 Starliner is aiming for a May 6 launch, carrying commander Barry "Butch" Wilmore and pilot Sunita "Suni" Williams on the Crew Flight Test. They will fly atop an Atlas V rocket from Cape Canaveral Space Force Station's Space Launch Complex 41.

The duo are looking to dock Starliner with the ISS for about eight days before bringing the spacecraft back home for a ground landing in the western U.S. It will pave the way for Boeing to begin regular service to the station as part of NASA's Commercial Crew Program, the remedy to reliance on Russia for ferry service to the ISS after the end of the space shuttle program in 2011.

"It's really exciting to finally get here to this day," said Williams, and "represent so many people who have worked for years to get this Boeing Starliner ready to go. We just happen to be the tip of the spear, the face of it, and take it to space.

Three companies are in the running to provide NASA's next moon rover for crewed missions planned later this decade, the space agency said Wednesday.

Texas-based Intuitive Machines—which landed a robot near the lunar south pole in February—Lunar Outpost of Colorado and Venturi Astrolab of California have been tasked with developing designs under a contract with a combined maximum potential value of $4.6 billion.