Continuing an ambitious testing schedule, SpaceX on Thursday prepared the world's most powerful rocket for its fourth flight, an attempt to launch the company's Starship upper stage into space and then bring it down through the heat of reentry for a controlled splashdown in space. the Indian Ocean.
The flight plan also called for the giant Super Heavy first stage booster to make a controlled descent to a “soft” landing in the Gulf of Mexico after propelling the spacecraft out of the lower atmosphere.
The two-hour launch window at SpaceX's “Starbase” facility in Boca Chica, Texas, was expected to open at 8 a.m. EDT. Duration of the mission, from start to finish: one hour and five minutes.
SpaceX
The 39-story Super Heavy-Starship rocket is by far the most powerful launch vehicle in the world with more than twice the launch power of the space shuttle, NASA's legendary Apollo program Saturn 5 and the agency's Space Launch System rocket designed for Artemis. moon rocket.
Powered by 33 methane-burning Raptor engines, the 230-foot Super Heavy booster generates a staggering 16 million pounds of thrust. It is designed to propel the spacecraft's upper stage out of the lower atmosphere before dropping away for a rocket-powered descent to landing, refurbishment and reuse.
The 50-meter-high spaceship, powered by six Raptors, is also designed to be fully reusable and can land tail first on Earth, the moon or even Mars.
However, recovery was not an option for the first test flights of the Super Heavy Starship. The goal was to “simply” return both stages intact and under control to the lower atmosphere. For Thursday's flight, both stages were programmed to perform rocket-powered descents that mimicked actual landing procedures. But both were expected to sink on impact.
“The fourth flight test shifts our focus from reaching orbit to demonstrating the ability to return and reuse Starship and Super Heavy,” SpaceX said on its website. “The primary objectives are to conduct a landing and soft landing in the Gulf of Mexico with the Super Heavy booster, and achieve controlled entry of the Starship.”
In three previous flights, two in 2023 and the most recent in March, the Super Heavy and Starship stages suffered catastrophic failures before all test objectives could be met. But with each flight, SpaceX implemented hardware and software upgrades that resulted in dramatically improved performance.
SpaceX
During the third test flight, the Starship's upper stage reached space, orbited the planet and began a planned descent over the Indian Ocean before breaking up in the upper atmosphere. The Super Heavy booster reached the lower atmosphere over the Gulf of Mexico before losing control.
But SpaceX called the flight an overall success and made more changes during Thursday's test to improve performance.
It is critical that the Super Heavy Starship flies regularly NASA's Artemis moon program. NASA awarded SpaceX a $2.9 billion contract in 2021 to develop a variant of the Starship upper stage to ferry astronauts from lunar orbit to the surface and back. Artemis crews will travel to and from the moon using Lockheed Martin-built Orion capsules.
To reach the moon, multiple Super Heavy tanker flights will need to be launched to robotically refuel the upper stage of a spacecraft already in low Earth orbit. The Starship lander will then fly itself to lunar orbit to wait for the Artemis moon walkers.
NASA's contract calls for one unmanned test flight on the moon landing before astronauts make an actual landing attempt. Artemis managers are aiming for the first moon landing with astronauts on board at the end of 2026.
But that will depend on whether SpaceX will launch enough Super Heavy-Starship flights to demonstrate reliability. Although SpaceX's philosophy is to fly regularly, learn from mistakes and fly again, NASA will need a long string of successful flights before the agency deems it safe to bring astronauts on board.
