• When the Starship launch commences, it will be the fifth uncrewed test flight of a vehicle for which Musk has grand ambitions beyond NASA moon missions.
• While SpaceX says it's ready for another test flight, the FAA has not yet approved another launch.
• This time around, SpaceX hopes for the first time to return the Super Heavy booster rocket intact to the launch site while the Starship makes a second splashdown in the Indian Ocean.

SpaceX insists it's ready to conduct another test of its Starship megarocket as soon as Sunday despite no word from federal regulators about whether the company will be approved in time to do so.

More than four months have already passed since SpaceX has launched a test flight of the behemoth 400-foot rocket that will one day ferry NASA astronauts to the lunar surface. While the Federal Aviation Administration has previously indicated that SpaceX would not have approval for another Starship launch before late November, CEO Elon Musk has argued that the vehicle has been ready since August.

Now, Musk and SpaceX are proclaiming that the next Starship demonstration could happen as early as Sunday, "pending regulatory approval," of course. When the Starship launch commences, it will be the fifth uncrewed test flight of a vehicle for which Musk has grand ambitions beyond NASA moon missions.

In the years ahead, Musk envisions Starship serving as the spacecraft to transport humans to Mars and deep in the cosmos as part of his oft-stated goal of making "life multiplanetary." But first, the Federal Aviation Administration needs to make a determination on a license for SpaceX to undergo another Starship launch.

Here's what to know about Starship and when the next test flight could possibly happen.

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When will Starship launch on next test flight?

SpaceX said on social media platform X late Monday that Starship's fifth flight test could launch as soon as Sunday, Oct. 13.

But for that to happen, the company would need the approval of the FAA, which licenses commercial rocket launches.

The regulatory agency, which has in the past indicated it did not expect to decide on a license until late November, said in a statement Wednesday to USA TODAY that it "will make a licensing determination once SpaceX has met all licensing requirements." The FAA's statement, which made no mention of the November timeframe, added that SpaceX submitted new information in mid-August for its proposed Starship launch that it continues to review.

The FAA declined to comment about the possibility of approval in time for a Sunday launch.

As of Thursday, it appeared that preparations for launch were underway at SpaceX's Starbase in Boca Chica near Brownsville, Texas.

SpaceX, FAA clash over regulations

SpaceX has often found itself at odds with the FAA in recent months over regulations that the company has vocally criticized.

Last month, the FAA announced a proposal to hit SpaceX with $633,009 in civil penalties for what the agency claims were failures by the company to follow license requirements ahead of two separate launches last year. In response, Musk took to his social media site X to indicate his plans to sue the agency for "regulatory overreach."

News of the proposed fines came on the heels of the FAA briefly grounding SpaceX's Falcon 9 rocket following a fiery landing mishap on an otherwise successful orbital satellite delivery.

Musk has routinely taken aim at federal regulators, both for the proposed fines and for what SpaceX has labeled a "superfluous" delay in approving the license for Starship's fifth test flight.

"Unfortunately, we continue to be stuck in a reality where it takes longer to do the government paperwork to license a rocket launch than it does to design and build the actual hardware," SpaceX wrote in a lengthy blog post in September. "This should never happen and directly threatens America's position as the leader in space."

What is the Starship?

SpaceX has spent years developing and testing the Starship, which is classified as a super heavy-lift launch vehicle and is lauded as the biggest and most powerful rocket ever built.

The entire craft features two components: The Starship spacecraft itself, and the "Super Heavy" rocket it's perched atop.

Ahead of the upcoming test flight, SpaceX engineers reworked the rocket's heatshield, replacing the entire thermal protection system with newer tiles and a backup ablative layer.

This time around, SpaceX hopes for the first time to return the Super Heavy booster rocket intact to the launch site.

The Starship itself is due to fly a similar trajectory as the previous flights before attempting a second successful splashdown in the Indian Ocean. The path does not require the vehicle to conduct a deorbit burn for reentry into Earth's atmosphere, though audible sonic booms are expected in the area around the landing zone as the returning booster slows down from supersonic speeds, SpaceX said.

The company said engineers have made extensive upgrades ahead of the flight test to the megarocket's hardware and software, as well as the infrastructure at Starbase itself.

"We accept no compromises when it comes to ensuring the safety of the public and our team, and the return will only be attempted if conditions are right," the company said in a statement.

Starship selected for NASA lunar missions

Starship is intended to play an integral role as early as 2026 when U.S. astronauts head back to the moon.

As part of NASA's ambitious Artemis campaign, the space agency's first lunar program since the Apollo era of the 1970s, SpaceX was paid a hefty $2.9 billion sum to develop a spacecraft capable of safely transporting astronauts from orbit to the moon's surface.

Under NASA's plans, Artemis III astronauts aboard the Orion capsule would rendezvous and dock with Starship while orbiting the moon. Two astronauts would then board the Starship for a ride to the lunar surface while the other two spacefarers remain on Orion.

In the years ahead, NASA's Artemis program aims to establish a lunar settlement on the south pole. One day, the water ice thought to be abundant in the region could be extracted and used for drinking, breathing and as a source of hydrogen and oxygen for rocket fuel to make crewed trips to Mars possible – such as the ones Musk is planning as early as 2028.

Starship's first crewed test flight is planned for the third and final mission under the Polaris Program, which SpaceX is funding along with billionaire entrepreneur Jared Isaacman. The inaugural spaceflight last month under the program, Polaris Dawn, included the first-ever commercial spacewalk with the crew aboard a Dragon capsule.

What happened on previous Starship tests?

Since April 2023, Starship has undergone four test flights.

The gargantuan rocket, which has so far only undergone uncrewed demonstration, managed to once again make it to orbit in its fourth and most recent test in June before accomplishing a first: splashing down for its first successful landing in the Indian Ocean.

While the rocket's first three tests ended in explosions, officials say it has improved in every demonstration they've conducted with the vehicle. That included its third demonstration in March, when SpaceX said Starship hit several key milestones and conducted a handful of in-flight tests that are a crucial step forward for it to be reliable and functional.

"By continuing to push our hardware in a flight environment, and doing so as safely and frequently as possible," SpaceX said, "we’ll rapidly bring Starship online and revolutionize humanity’s ability to access space."

Contributing: Mary Walrath-Holdridge, USA TODAY

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