NASA astronauts, stuck on ISS after issues with Boeing's Starliner, to give press conference

The NASA astronauts who were aboard the first crewed flight into space on Boeing's Starliner will participate in a press conference on Wednesday morning.

Flight commander Barry "Butch" Wilmore, 61, a former U.S. Navy captain, and Sunita Williams, 58, a former Navy service member, the flight's pilot, both of whom are currently aboard the International Space Station (ISS), are set to answer questions about the test flight and the mission.

Wilmore and Williams lifted off on June 5 from Cape Canaveral Space Force Station in Florida and docked with the ISS on June 6.

The pair were initially expected to spend one week aboard the ISS evaluating the spacecraft and its systems and return June 14. However, Starliner has experienced several mechanical issues, including helium leaks and a thruster issue, leaving the astronauts stuck onboard the ISS with no set return date.

NASA has insisted Wilmore and Williams are safe while they remain onboard the ISS with the Expedition 71 crew. The agency has said the ISS has plenty of supplies in orbit, and the station's schedule is relatively open through mid-August.

"I want to make it clear that Butch and Suni aren't stranded in space," Steve Stich, manager of NASA's Commercial Crew program, said during a June 28 teleconference. "Our plan is to continue to return them on Starliner and return them home at the right time."

NASA and Boeing say Wilmore and Williams are "integrated" with the Expedition 71 crew aboard the ISS and are helping the crew with station operations as needed, as well as completing "objectives" needed for NASA's possible certification of Starliner.

"Since their arrival on June 6, Wilmore and Williams have completed half of all hands-on research time conducted aboard the space station, allowing their crewmates to prepare for the departure of Northrop Grumman's Cygnus spacecraft," NASA wrote in a recent update.

This week, teams at NASA's White Sands Test Facility in New Mexico are performing ground tests of Starliner's thruster, putting it through similar conditions the spacecraft experienced on its way to the ISS, according to an update on Boeing's website.

The tests will replicate Starliner's docking, when some of the thrusters failed, and what the thrusters will experience from undocking to landing back on Earth.

"We really want to understand the thruster and how we use it in flight," said Dan Niedermaier, the lead Boeing engineer for the thruster testing, in a statement. "We will learn a lot from these thruster firings that will be valuable for the remainder of the Crew Flight Test and future missions."

Starliner has been plagued by issues even before launch. The flight test was originally tentatively scheduled for May 6, but was scrubbed after a problem with an oxygen valve on a rocket from United Launch Alliance, which manufactures and operates the rockets that launch Starliner spacecraft into orbit.

A new launch date was subsequently set for May 25, but then a small helium leak was discovered in the Starliner service module, which contains support systems and instruments for operating the spacecraft.

Those helium leaks and a thruster issue threatened to delay Starliner's docking, but it docked successfully. Five days after docking at the ISS, NASA and Boeing announced that the spacecraft was experiencing five "small" helium leaks, but added at the time that enough helium remained for the return mission.