Two NASA astronauts are stuck in space for at least another 10 days and perhaps longer as officials try to address problems with Boeing’s Starliner spacecraft.

On June 5, a Starliner launched flight commander Barry “Butch” Wilmore and flight pilot Sunita “Suni” Williams to the International Space Station. Helium leaks and a thruster issue emerged to keep the Starliner in space.

Wilkmore and Williams were initially expected to return on June 14. No official date for their return exists, according to ABC.

Reuters, citing NASA sources it did not name, said the earliest date being considered is July 6.

Boeing told Newsweek that the helium leaks and thruster issues were “not a concern” with only one of 27 thrusters still balky.

Boeing said a spacewalk planned for July 2 will be a key to deciding when a return flight takes place.

“I have a great deal of confidence they are looking at it very hard and they would not commit to the de-orbit of a spacecraft that was unsafe,” Wayne Hale, the former NASA space shuttle program director who directed for 40 shuttle flights said, according to The Washington Post.

The certification process that would allow Boeing to join SpaceX as an approved launch provider is a “painstaking review,” Hale said.

Hale said that “clearly these two issues need to be resolved” before NASA gives Boeing its full approval, adding  “thruster failures and helium leaks are something we dealt with all the time in the shuttle program. They were very common.”

Hale said the space shuttle Columbia disaster of 2003, when the craft disintegrated in its return to Earth, is on the minds of those vetting Starliner’s safety.

“Those lessons are not forgotten,” he said.

“We are taking our time and following our standard mission management team process,” Steve Stich, manager of NASA’s Commercial Crew Program, said. “We are letting the data drive our decision making relative to managing the small helium system leaks and thruster performance we observed during rendezvous and docking.”

Last week, Stich said NASA was “not going to go fly another mission like this with the helium leaks.”

The helium and thruster problems are located within Starliner’s service module, which gives Starliner most of its power, but also is jettisoned and burns up upon re-entry.

Because “the service module doesn’t come back, they have to get all the data they can from it now,” Mike Massimino, a former NASA astronaut and a professor of mechanical engineering at Columbia University, said. “You’d want to stay on orbit as long as you can to get that data.”

Makena Young, a fellow with the Aerospace Security Project at the Center for Strategic and International Studies, told Fox News that repairs are a challenge in space.

“Operating in space, building these spacecraft, especially human-rated spacecraft for commercial companies, is a new endeavor that’s still incredibly technical. It’s a really hard operating environment when things go wrong … It’s not like you can go to take it to a mechanic when you’re in space,” she said.

“This is an incredibly important mission,” Young said. “These delays seem like a bad thing, and can erode confidence that you have in the system … but you really want to make sure that there are no questions in the back of your mind when you’re saying, ‘OK, yes, this is ready to launch humans.’ They’re definitely necessary.”