Astronauts stranded in space due to multiple issues with Boeing's Starliner — and the window for a return flight is closing

Two NASA astronauts who rode to orbit on Boeing's Starliner are currently stranded in space aboard the International Space Station (ISS) after engineers discovered numerous issues with the Boeing spacecraft. Teams on the ground are now racing to assess Starliner's status.

Astronauts Butch Wilmore and Suni Williams were originally scheduled to return to Earth on June 13 after a week on the ISS, but their stay has been extended for a second time due to the ongoing issues. The astronauts will now return home no sooner than June 26th, according to NASA.

After years of delays, Boeing's Starliner capsule successfully blasted off on its inaugural crewed flight from Florida's Cape Canaveral Space Force Station at 10:52 a.m. EDT on June 5. But during the 25-hour flight, engineers discovered five separate helium leaks to the spacecraft's thruster system.

Now, to give engineers time to troubleshoot the faults, NASA has announced it will push back the perilous return flight, extending the crew's stay on the space station to at least three weeks. 

"We've learned that our helium system is not performing as designed," Mark Nappi, Boeing's Starliner program manager, said at a news conference on June 18. "Albeit manageable, it's still not working like we designed it. So we've got to go figure that out."

The return module of the Starliner spacecraft is currently docked to the ISS's Harmony module as NASA and Boeing engineers assess the  vital hardware issues aboard the vessel, including five helium leaks to the system that pressurizes the spacecraft's propulsion system, and five thruster failures to its reaction-control system. 

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