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SpaceX’s Starship, the most powerful launch vehicle ever built, is set to take off for its fourth flight test on Thursday. The highly anticipated event will be the company’s second uncrewed test in 2024.
SpaceX aims to mark new milestones this time around, such as demonstrating the reusability of the Starship vehicle.
The 120-minute launch window opens at 7 a.m. CT (8 a.m. ET), with an expected launch at 7:50 a.m. CT (8:50 a.m. ET), and the company will stream live coverage on X, formerly known as Twitter this, about 30 minutes before the launch. Weather conditions are 95% favorable for the launch, according to SpaceX.
The Starship launch system, which includes the upper Starship spacecraft and a rocket booster called the Super Heavy, will attempt to take flight from the private Starbase facility in Boca Chica, Texas.
The flight test comes two days after the Federal Aviation Administration, which authorizes commercial rocket launches, gave SpaceX approval. And the test is taking place one day after SpaceX’s competitor under NASA’s Commercial Crew Program, Boeing, successfully launched the first crewed mission of the Starliner, which is carrying two veteran NASA astronauts to the International Space Station.
Each Starship test flight has different objectives that build on the lessons learned and milestones achieved during the previous flight.
SpaceX is now focusing on “demonstrating the ability to return and reuse Starship and Super Heavy. The main objectives are to complete a landing burn and soft splashdown in the Gulf of Mexico with the Super Heavy booster, and achieve a controlled entry of Starship,” according to a company release.
A starship is expected to flash in the Indian Ocean.
The Starship team made software and hardware upgrades to the launch system to incorporate lessons learned from the third flight.
“The fourth Starship flight will aim to bring us closer to the rapidly reusable future on the horizon,” according to SpaceX. “We are continuing to rapidly develop Starship, putting flight hardware in a flight environment to learn as quickly as possible while building a fully reusable transport system designed to carry crew and cargo into orbit Earth, the Moon, Mars and beyond.”
Three wild test flights
The first two attempts to get Starship up to orbital speeds ended in explosions in 2023, when the spacecraft and booster burst into flames before reaching their intended landing sites.
SpaceX has been known to deal with fiery disasters in the early stages of spacecraft development, saying that these failures help the company quickly implement design changes that lead to better results.
SpaceX said its approach to rocket development is focused on speed. The company uses an engineering method called “spiral rapid development”. Essentially this process is about a desire to build prototypes quickly and a willingness to blow them up to learn how to build a better one – faster than if the company were to rely solely on ground tests and simulations.
After the first and second explosive Starship test flights, the company immediately tried to frame those adventures as successes.
The third nearly hour-long test flight, conducted in March, achieved several milestones before it separated after re-entry, rather than splashing down in the Indian Ocean.
Initially, Starship reached speeds close to what would be required to put the vehicle into orbit. Typically, such a feat requires speeds in excess of 17,500 miles per hour (28,000 kilometers per hour). Starship reached its target orbital speeds and did not aim to enter orbit on the third flight.
The Starship’s payload door – a hatch that must be opened for the spacecraft to deploy satellites into space after they reach orbit – popped open before opening in a crucial test of that mechanism.
SpaceX also performed a “propellant transfer demonstration,” or moving a portion of the propellant aboard the Starship vehicle from one tank to another. SpaceX engineers designed the display to test how Starship will be refueled on future missions while in orbit.
But after a bright halo of red plasma, created by extreme heat and pressure as Starship re-entered Earth’s atmosphere, flared around the vehicle, the crew lost communication with the spacecraft.
However, SpaceX did not intend to recover Starship after this flight test.
The Super Heavy booster was also expected to make an autonomous, controlled landing in the ocean, but the booster was lost when all its engines failed to ignite.
But both Starship’s spacecraft and booster managed to fly further than the two previous tests in 2023.
gargantuan Starship targets
A lot is riding on Starship’s eventual success. SpaceX CEO Elon Musk has repeatedly said that the rocket is central to the company’s founding mission: to put humans on Mars for the first time.
NASA has selected the Starship spacecraft for a central role in its Artemis program to return humans to the moon for the first time in more than five decades. Under the federal space agency’s current road map, Starship would complete the final part of a crewed mission to the moon, taking the astronauts from a spacecraft in lunar orbit and landing them on the surface. The United States is in a race with China, trying to be the first to develop a permanent lunar outpost and set the precedent for deep space settlements.
Milestones such as transfer of propellant from third flight test objectives for the future. Cutting off the spacecraft’s fuel will be critical for high-profile Starship missions down the road.
When Starship makes a trip to the moon under Artemis – it will have to sit in close-Earth orbit while SpaceX sends special support vehicles that will carry fuel to the spacecraft. To get to the moon, SpaceX may have to make more than a dozen refueling trips.
The first astronaut is landing under the Artemis program as early as September 2026.
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