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SpaceX is about to launch the latest test flight of Starship, the most powerful rocket system ever built, which could one day be used to take humans to the moon and Mars.
The launch of the Super Heavy rocket booster, carrying the unmanned Starship spacecraft, is expected to occur during a 30-minute launch period beginning at 8 a.m. ET from SpaceX's Starbase facility in Boca Chica, Texas.
For the first time, this demonstration mission aims to include an ambitious attempt to maneuver the 71-meter-tall rocket booster onto a giant landing structure after it burns through most of its fuel and separates from the upper spacecraft. spacecraft. The Super Heavy may be captured in mid-air with a pair of enormous metal tongs, which SpaceX calls "chopsticks."
Meanwhile, the Starship spacecraft will continue to fly independently, using its six onboard engines, before practicing a landing maneuver over the Indian Ocean. SpaceX does not expect the uppermost spacecraft to be recovered.
The goal of each milestone is to figure out how SpaceX could one day recover and quickly deploy Super Heavy boosters and Starship spacecraft for future missions. Rapidly reusing rocket parts is considered essential to SpaceX's goal of dramatically reducing the time and costs required to deliver cargo - or ships carrying people - to Earth orbit and deep space.
SpaceX ultimately plans to use the Starship capsule as a landing vehicle that will carry NASA astronauts to the moon's surface as early as 2026 as part of the Artemis III mission, and the company has government contracts worth nearly $4 billion to tackle the task complete. Ultimately, SpaceX also hopes that Starship will put the first people on Mars.
Pushing the envelope
Spacecraft development has thus far focused on a series of increasingly complex test flights, which began in 2019 with short hop tests of a vehicle nicknamed 'Starhopper' that initially lifted just a few centimeters off the ground. More recently, the company has moved on to bolder 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 - kicked off in April 2023. That launch was solely intended to get the 121-meter-long vehicle off the launch pad. And that's exactly what it did before exploding over the Gulf of Mexico just minutes into the flight.
SpaceX has been known to embrace serious mishaps in the early stages of spacecraft development, saying these failures help the company quickly make design changes that lead to better results.
The company's goals have become more ambitious with each new launch.
The latest test launch - the fourth of SpaceX's integrated test flight campaign - kicked off in June. Both the booster and spacecraft, despite showing a badly scorched and wobbly wing during the webcast, survived reentry into Earth's atmosphere and practiced landing maneuvers over the ocean, a significant step forward.
In Mechazilla's arms
SpaceX now wants to expand its testing even further by attempting to retrieve the Super Heavy booster after launch.
Ultimately, SpaceX plans to recover and reuse both the Super Heavy and Starship spacecraft. But eliminating booster recovery is a natural first step, as SpaceX has extensive experience in that area.
Landing rocket boosters after flight is a feat SpaceX has mastered with its smaller workhorse rocket, the Falcon 9. Boosters from that rocket have made soft touchdowns on seafaring platforms or ground platforms after more than 330 launches - allowing those vehicles to be refurbished and could be flown again. SpaceX says this has lowered its costs, allowing the company to undercut the rest of the rocket market.
However, Starship is a much more powerful and complex system.
With 33 engines at its base, each more powerful than any of the nine used on the Falcon, the Super Heavy booster has about ten times the thrust at takeoff.
Rather than strap landing legs to the side of the Super Heavy, like those that adorn a Falcon 9's booster, SpaceX instead built a special tower to support the Super Heavy's return to solid ground, hoping that this will make the recovery process even faster.
The tower, dubbed "Mechazilla" by SpaceX CEO Elon Musk for its resemblance to a metal Godzilla, has massive metal arms. The arms, or "chopsticks," can be used to stack and move boosters and spacecraft at the launch site before they take off - and they are designed to essentially catch the vehicles in mid-air as they return to Earth.
Musk's vision is that the chopstick arms will eventually be able to simply turn around and place a rocket back on the launch pad within minutes of its return - allowing the vehicle to take off again once it is refueled - perhaps just 30 minutes after landing. The CEO said this in an interview on June 5.
Starship's chances of success
It's a bold vision. And SpaceX is still in the early stages of figuring out exactly how the catch will work.
Musk acknowledged during a July interview on YouTube that SpaceX's goal for this flight "sounds a little crazy," though it "has a decent chance of success."
"We're not breaking physics," he said, "so success is one of the possible outcomes here."
One problem Starship encountered during its fourth test flight in June, Musk added, was the loss of heat shield tiles - or thousands of small, black hexagons attached to the spacecraft's exterior that were intended to protect the vehicle from extreme temperatures during the return. The loss of a large number of those tiles, according to Musk, hampered the vehicle's ability to make a soft landing.
"Because of lost tiles ... the front flaps were so melted that it was like trying to control them with little skeleton hands," Musk said, adding that the fourth flight was about 6 miles (9.7 kilometers) from its intended ocean landing site. .
During the fifth test flight, the uppermost Starship spacecraft will again attempt to land upright in a controlled maneuver over the ocean.
The company states on its website that it has performed a "complete rework of its heat shield, with SpaceX engineers spending more than 12,000 hours replacing the entire thermal protection system with newer generation tiles, a backup ablative layer and extra protection between the flap structures. ."
That could help Starship better survive the atrocities of the return.
If this flight is successful, it could push the company to take on much more ambitious projects. For example, SpaceX must figure out how to fuel a Starship spacecraft while stationed in orbit. Such a maneuver will be necessary to provide the massive vehicle with enough propellant to make the journey to the moon.
If the company fails to achieve its goals or causes substantial damage to its launch facilities, it could raise questions about additional delays to NASA's moon ambitions.
Artemis, the flagship of NASA's human spaceflight program, aims to land astronauts on the moon's surface for the first time since the Apollo program ended more than 50 years ago.
The federal space agency has already warned that its goal of making the first manned landing on the lunar surface in 2026 may be held up by Starship's development timeline.
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