SpaceX has lined up the sixth test flight of its powerful Starship and Super Heavy rocket from its Texas facility Starbase on Tuesday aiming for another catch of the booster back on land and a first-time refiring of one of the upper stage’s engines while in space.

Liftoff is targeted for a 30-minute window that opens at 5 p.m. EST from the company’s test facility in Boca Chica, Texas, and would mark the fourth test flight for Starship this year.

Powered by 33 Raptor engines on the Super Heavy booster, it launches from the pad with more than 16 million pounds of thrust, which makes it the most powerful rocket to have made it into space.

SpaceX makes ‘absolutely insane’ catch of Starship’s massive Super Heavy booster

The last test flight occurred just five weeks ago, and marked the first time the Super Heavy booster attempted a recovery landing back at the launch site, returning to the launch tower nicknamed “Mechazilla,” and making a pinpoint thrust-in-place maneuver so a pair of support arms called “chopsticks” were able to safely capture it.

“Starship’s fifth flight test was a seminal moment in iterating towards a fully and rapidly reusable launch system,” the company posted on its website.

It also had an improved suborbital flight of the upper Starship stage that made controlled landing halfway around the world in the Indian Ocean, although one that ended with an explosion.

Tuesday’s test flight aims to repeat those feats, but add on reignition of one of the six upper stage Raptor engines in space as well as perform heat shield experiments and maneuver changes while on reentry in an effort to get that return trip to Earth more in control.

“The success of the first catch attempt demonstrated the design feasibility while providing valuable data to continue improving hardware and software performance,” SpaceX posted. “Hardware upgrades for this flight add additional redundancy to booster propulsion systems, increase structural strength at key areas, and shorten the timeline to offload propellants from the booster following a successful catch.”

A repeat of the crowd-pleasing booster return that features a sonic booms as it comes in at supersonic speeds will still need to satisfy all of the safety criteria as it makes its way back to the Texas launch site, and a manual command from the mission’s flight director, the company stated.

“If this command is not sent prior to the completion of the boostback burn, or if automated health checks show unacceptable conditions with Super Heavy or the tower, the booster will default to a trajectory that takes it to a landing burn and soft splashdown in the Gulf of Mexico,” SpaceX posted. “We accept no compromises when it comes to ensuring the safety of the public and our team, and the return will only take place if conditions are right.”

The upper stage is flying the same suborbital trajectory, but since it’s launching in the early evening from Texas, it will mean landing amid daylight in the Indian Ocean where it will have turned morning already.

The added single-engine burn while in space paves the way for the deorbit burns that would be needed on future orbital missions.

The upper stage is still feeling the intense heat of reentry and SpaceX continued to test out thermal protection experiments to find the safest options for future Starship recovery plans, and eventual reuse.

“The flight test will assess new secondary thermal protection materials and will have entire sections of heat shield tiles removed on either side of the ship in locations being studied for catch-enabling hardware on future vehicles,” SpaceX posted. “The ship also will intentionally fly at a higher angle of attack in the final phase of descent, purposefully stressing the limits of flap control to gain data on future landing profiles.”

The plans for the seventh test flight include launching with upgraded features based on Tuesday’s results getting closer to a fully reusable heat shield.

“Learnings from this and subsequent flight tests will continue to make the entire Starship system more reliable as we close in on full and rapid reusability,” SpaceX posted.

Company founder Elon Musk wants to use Starship for eventual colonization of Mars.

“A fully reusable rocket with orbital refilling is the critical breakthrough needed to make life multiplanetary,” he posted on X. “For the first time in 4.5 billion years.”

The first two Starship launch attempts in 2023 ended explosively without achieving orbit, but it’s had three successful suborbital flights since with increasing improvements on both booster and upper stage reentry.

The two stages of the rocket stand at 396 feet tall, and all test launches so far have been from the Boca Chica site, but SpaceX plans to build Starship launch sites at both Kennedy Space Center and Cape Canaveral Space Force Station.

The FAA and the Department of the Air Force both are heading up environmental-impact studies at both Space Coast sites.

NASA has a vested interest in SpaceX succeeding with its next-generation rocket, a version of which is tasked with bringing the astronauts on NASA’s Artemis III mission down to the surface of the moon. That mission is still aiming for late 2026 but could be delayed if Starship isn’t at full speed by then.