By Jackie Wattles and Ashley Strickland, CNN
Photo: Twitter/SpaceX
SpaceX has successfully launched the latest test flight of Starship on Sunday morning (Monday NZ time), the most powerful rocket system ever constructed, which could one day be used to carry humans to the moon and Mars.
Liftoff of the Super Heavy rocket booster, topped with the uncrewed Starship spacecraft, occurred at 8.25am ET during a 30-minute launch window that opened at 8am ET from SpaceX's Starbase facility in Boca Chica, Texas.
For the first time, this demonstration mission included an ambitious attempt to manoeuvre the 232-foot-tall (71-metre) rocket booster to a gargantuan landing structure after it burned through most of its fuel and broke away from the upper Starship spacecraft. The Super Heavy was successfully caught midair with a pair of massive metal pincers, which SpaceX calls "chopsticks."
Meanwhile, the Starship spacecraft continued flying on its own, using its six onboard engines, before practising a landing manoeuvre over the Indian Ocean. SpaceX does not expect to recover the upper spacecraft.
The goal for each milestone is to hash out how SpaceX might one day recover and rapidly refly Super Heavy boosters and Starship spacecraft for future missions. Quickly reusing rocket parts is considered essential to SpaceX's goal of drastically reducing the time and cost of getting cargo - or ships of people - to Earth's orbit and deep space.
SpaceX ultimately plans to use the Starship capsule as the landing vehicle that will ferry NASA astronauts to the lunar surface as soon as 2026 as part of the Artemis III mission, and the company has government contracts worth up to nearly $4 billion (NZ$6.5 billion) to complete the task. Eventually, SpaceX also hopes that Starship will put the first humans on Mars.
Pushing the envelope
Starship development has so far centred on a series of increasingly complex test flights, beginning in 2019 with brief hop tests of a vehicle nicknamed "Starhopper" that initially lifted mere inches off the ground. More recently, the company has moved on to more daring launches of the fully stacked Starship capsule and Super Heavy booster.
The inaugural test launch of a Starship and Super Heavy - called an integrated test flight - took off in April 2023. That launch aimed solely to get the 397-foot (121-metre) vehicle off the launchpad. And it did just that before exploding minutes into flight over the Gulf of Mexico.
SpaceX is known to embrace fiery mishaps in the early stages of spacecraft development, saying these failures help the company rapidly implement design changes that lead to better results.
The company's goals have grown more ambitious with each additional launch.
The last test launch - the fourth of SpaceX's integrated test flight campaign - took off in June. Both the booster and spacecraft, despite displaying a badly scorched and wobbly wing during the webcast, survived re-entry into Earth's atmosphere and practised touchdown manoeuvres over the ocean, a significant step forward.
Into Mechazilla's arms
SpaceX pushed its testing even further by retrieving the Super Heavy booster post-launch.
Ultimately, SpaceX plans to recover and reuse both the Super Heavy and the Starship spacecraft. But hashing out booster recovery is a natural first step, as SpaceX has extensive experience in that arena.
Landing rocket boosters after flight is a feat that SpaceX mastered with its smaller workhorse rocket, the Falcon 9. Boosters from that rocket have made soft touchdowns on seafaring platforms or ground pads after more than 330 launches - allowing those vehicles to be refurbished and flown again. SpaceX said that has driven down its costs, allowing the company to undercut the rest of the rocket market.
Starship, however, is a far more powerful and complex system.
With 33 engines at its base, each more powerful than one of the nine used on the Falcon, the Super Heavy booster packs roughly 10 times the amount of thrust at lift-off.
Rather than strapping landing legs onto the side of the Super Heavy like the ones that adorn a Falcon 9's booster, SpaceX instead built a special tower to support the Super Heavy's return back to terra firma, hoping this will make the recovery process even quicker.
The tower, dubbed "Mechazilla" by SpaceX chief executive Elon Musk for its likeness to a metallic Godzilla, has massive metal arms. The arms, or "chopsticks," can be used to stack and move boosters and spacecraft at the launch site before takeoff - and they are designed to essentially catch the vehicles mid-air as they return to Earth.
Musk's vision is that the chopstick arms will ultimately be able to simply turn around and set a rocket back on the launchpad within minutes of its return - allowing the vehicle to take off again once it's refuelled - perhaps as little as 30 minutes after touchdown, he said in a June 5 interview.
The odds of Starship's success
It's a bold vision. And SpaceX is still in the early stages of hashing out exactly how the catch works.
Musk acknowledged during a July interview posted to YouTube that SpaceX's goal for this flight "sounds kind of insane," though its "got a decent chance of working."
"We're not breaking physics," he said, "So success is one of the possible outcomes here."
SpaceX caught the Super Heavy booster under the criteria that "thousands of distinct vehicle and pad criteria are met," according to the company's website, which required "healthy systems on the booster and tower and a manual command from the mission's Flight Director."
If the attempt had been waved off, Super Heavy would have attempted its landing manoeuvre over the ocean once again.
The attempt occurred about seven minutes after launch, while the Starship spacecraft coasted for nearly one hour before making its controlled splashdown in the Indian Ocean.
One problem that Starship encountered during its fourth test flight in June, Musk added, was the loss of heat shield tiles - or thousands of small, black hexagons affixed to the spacecraft's exterior that are meant to shield the vehicle from extreme temperatures during re-entry. Losing a large number of those tiles deeply hindered the vehicle's ability to attempt a soft landing, according to Musk.
"Because of lost tiles, the forward flaps were so melted it was like trying to control it with little skeleton hands," Musk said, adding that the fourth flight landed roughly 6 miles (9.7 kilometres) away from its intended splashdown site in the ocean.
The company states on its website that it carried out a "complete rework of its heatshield, with SpaceX technicians spending more than 12,000 hours replacing the entire thermal protection system with newer-generation tiles, a backup ablative layer, and additional protections between the flap structures."
That could help Starship better survive the brutalities of re-entry.
The successful flight could cue up the company to tackle far more ambitious projects. For example, SpaceX must figure out how to refuel a Starship spacecraft while it's stationed in orbit. Such a manoeuvre will be necessary to give the massive vehicle enough propellant to make the journey out to the moon.
If the company failed to reach its goals or created substantial damage to its launch facilities, it could have raised questions about additional delays for NASA's lunar ambitions.
Artemis, NASA's flagship human spaceflight programme, is aiming to put astronauts on the surface of the moon for the first time since the Apollo programme ended more than 50 years ago.
Already, the federal space agency has warned that its goal of making the first crewed landing on the lunar surface in 2026 may be held up by Starship's development timeline.
- CNN