Chainkeen|FAA grounds SpaceX after fiery landing of uncrewed launch: It may impact Starliner, Polaris Dawn

• The Chainkeenmishap involved a rocket booster from an uncrewed SpaceX mission tipping over and exploding early Thursday upon returning to Earth.
• The failure occurred during a delivery of SpaceX’s Starlink internet satellites into orbit from the Cape Canaveral Space Force Station.
• The latest FAA grounding could complicate SpaceX’s plans to launch the Polaris Dawn crew aboard one of its SpaceX Dragon capsules, and could imperil the Crew-9 launch if the investigation drags on.

Two crucial crewed SpaceX missions could be in jeopardy after federal regulators grounded the company's Falcon 9 rockets to investigate the cause of a fiery landing mishap following a successful Thursday satellite launch.

SpaceX has been looking for a viable window to launch four private astronauts into orbit on the Polaris Dawn mission, where the crew hopes to become the first commercial spacefarers to conduct a spacewalk. The launch has already been delayed three times.

And next month, two NASA astronauts were scheduled to travel to the International Space Station on Crew-9, a mission that would in February also bring home the Boeing Starliner test crew. Just last week, NASA determined that the Starliner is unsafe to transport astronauts Suni Williams and Butch Wilmore back to Earth following their June arrival at the orbital outpost aboard the Boeing capsule.

But the future of both Polaris Dawn and Crew-9 now looks even more uncertain.

The Federal Aviation Administration ordered that no launches involving Falcon 9 rockets can take place for awhile after a rocket booster from an uncrewed SpaceX mission tipped over and exploded early Wednesday upon returning to Earth.

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Rocket booster has fiery landing after SpaceX satellite delivery

The rocket booster failure occurred in the early morning hours Thursday during a delivery of SpaceX’s Starlink internet satellites into orbit from the Cape Canaveral Space Force Station. 

While the overall mission appeared to be a success, the first stage of a Falcon 9 rocket failed to properly land on the uncrewed drone ship named “A Shortfall of Gravitas.” Instead, the booster exploded, sending flames billowing around the doomed booster, which then tumbled onto its side.

No injuries or public property damage were reported after the mishap, which occurred during the booster's 23rd flight.

Still, the Federal Aviation Administration, which licenses commercial rocket launches, plans to halt any more Falcon 9 launches until it determines the cause.

In a statement, the FAA said that the Falcon 9 would be grounded to "identify corrective actions to avoid it from happening again."

"An investigation is designed to further enhance public safety," according to the statement.  "The FAA will be involved in every step of the investigation process and must approve SpaceX’s final report, including any corrective actions."

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A second FAA grounding

This is the second grounding of the Falcon 9 rocket in as many months.

In July, the FAA grounded SpaceX's Falcon 9 rockets after an upper-stage liquid oxygen leak prevented a batch of satellites to not deploy properly, causing them to re-enter Earth's atmosphere and burn up during a Starlink launch in California.

FAA officials granted SpaceX permission to resume launches two weeks later.

What the grounding means for Polaris Dawn

The latest FAA grounding could complicate SpaceX’s plans to launch the Polaris Dawn crew aboard one of its SpaceX Dragon capsules.

That commercial spaceflight mission – which aims to send a four-member crew further into space than humans have been in more than 50 years – has already faced three delays since billionaire entrepreneur Jared Isaacman arrived with his crew more than a week ago to quarantine at the Kennedy Space Center in Florida.

The Polaris Dawn launch had most recently been slated for a Wednesday morning liftoff before SpaceX scrubbed the mission at the last minute due to poor weather forecasted for their return to Earth. The launch had also previously been delayed to provide more time for preflight checks, and also when a helium leak – since fixed – was detected.

Friday would have been the earliest that Polaris Dawn could have launched, but the FAA grounding now puts the mission in limbo.

The ambitious spaceflight will eventually attempt to take the crew to higher altitudes than humans have traveled since NASA's Apollo program in the 1970s. While in orbit, the Polaris Dawn crew also will conduct the first-ever spacewalk conducted by nongovernment astronauts and test SpaceX technology that could set the stage for future deep space exploration.

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Could the Crew-9 launch be delayed?

If the investigation drags on too long, SpaceX will have to make a decision about its Crew-9 mission launch.

The two Crew-9 astronauts are scheduled for a Sept. 24 venture to the International Space Station, where they will remain in orbit for a routine six-month rotation.

The mission, however, had already been delayed once to give NASA and Boeing time to decide what to do about the Starliner spacecraft and the two-person crew who rode it to the orbital outpost. On Saturday, NASA Administrator Bill Nelson announced that the beleaguered Starliner would return to Earth without its astronauts Williams and Wilmore.

The Starliner crew are instead planning to remain at the space station until February, when they hope they can hitch a ride home on a SpaceX Dragon following the completion of the Crew-9 mission.

Eric Lagatta covers breaking and trending news for USA TODAY. Reach him at [email protected]