SpaceX's Crew-9 astronaut launch delayed to Sept. 24 due to Boeing Starliner issues

SpaceX's next astronaut mission won't get off the ground this month after all.

Crew-9, SpaceX 's ninth operational flight to the International Space Station (ISS) for NASA, had been targeted to lift off on Aug. 18 . But it has been pushed back to no earlier than Sept. 24, the agency announced today (Aug. 6).

"This adjustment allows more time for mission managers to finalize return planning for the agency’s Boeing Crew Flight Test currently docked to the orbiting laboratory," NASA said in an update this afternoon .

Crew Flight Test (CFT) is the first-ever astronaut mission of Boeing's new Starliner capsule. It launched June 5 , carrying NASA's Suni Williams and Butch Wilmore to the ISS for a planned weeklong stay.

Starliner is still up there, however. The capsule experienced several issues on its way to the orbiting lab — most notably, the failure of five of its 28 reaction control system thrusters. CFT team members have been studying the problem ever since, trying to determine if and when Starliner can safely return Williams and Wilmore to Earth .

That work is still underway.

Related: Boeing Starliner 1st astronaut flight: Live updates

"NASA and Boeing continue to evaluate the spacecraft's readiness, and no decisions have been made regarding Starliner's return," NASA officials said in today's update.

We may get more clarity on Wednesday (Aug. 7): NASA will hold a press conference at 12:30 p.m. EDT (1630 GMT) "with agency leadership to discuss ongoing operations, including NASA's Crew-9, Crew-8, and Crew Flight Test missions."

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SpaceX's Crew-8 flight is gearing up to return to Earth; it arrived at the ISS in early March, delivering four astronauts to the orbiting lab for a roughly six-month stay.

The Crew-9 astronauts are commander Zena Cardman, pilot Nick Hague, mission specialist Stephanie Wilson and mission specialist Alexsandr Gorbunov. Cardman, Hague and Wilson are NASA astronauts, whereas Gorbunov represents Russia's space agency, Roscosmos .