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Starship, SpaceX’s most powerful launch vehicle ever built, will go on its fourth flight test on Thursday. The highly anticipated event will be the company’s second unmanned test in 2024.
This time, SpaceX aims to mark new milestones, such as demonstrating the reusability of its Starship vehicle.
The 120-minute launch window opens at 7 a.m. CT (8 a.m. ET), with the launch expected at 7:50 a.m. CT (8:50 a.m. ET), and the company will broadcast live on X, formerly known as Twitter. 30 minutes before departure. According to SpaceX, weather conditions are 95% suitable for launch.
The Starship launch system, which includes the upper Starship spacecraft and a rocket booster known as Super Heavy, will attempt to fly from the private Starbase facility in Boca Chica, Texas.
The flight test took place two days after the Federal Aviation Administration, which licenses commercial rocket launches, gave SpaceX the go-ahead. The test comes a day after Boeing, SpaceX’s rival under NASA’s Commercial Crew Program, successfully launched the first crewed mission of the Starliner, carrying two senior NASA astronauts to the International Space Station.
Each of Starship’s test flights has different objectives based on 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.” According to a company statement, the primary objectives will be to perform a landing burn and soft splash in the Gulf of Mexico with the Super Heavy booster and to enable controlled entry of Starship.”
Starship is expected to land in the Indian Ocean.
The Starship team made software and hardware upgrades to the launch system to incorporate lessons learned from the third flight.
According to SpaceX, “Starship’s fourth flight will aim to bring us closer to the rapidly reusable future on the horizon.” “We continue to rapidly develop Starship, putting the flight hardware into a flight environment that will be learned as quickly as possible, while building a fully reusable transportation system designed to carry crew and cargo to Earth orbit, the Moon, Mars and beyond.”
Three crazy test flights
The first two attempts to accelerate Starship to orbital speed in 2023 ended in explosions, with the spacecraft and booster bursting into flames before reaching their intended landing sites.
SpaceX has been known to encounter fiery setbacks in the early stages of spacecraft development, and those failures helped the company quickly implement design changes that led to better results, he says.
SpaceX said its approach to rocket development is geared towards speed. The company uses an engineering method called “rapid spiral development.” This process mainly stems from the desire to build prototypes quickly and willingly blow them up to learn how to build a better prototype; this is faster than if the company relied solely on ground tests and simulations.
After the explosive first and second Starship test flights, the company immediately tried to portray these setbacks as successes.
The third test flight, lasting about an hour in March, reached several milestones before breaking up after re-entry rather than splashing into the Indian Ocean.
First, Starship reached speeds close to the speed required to put the vehicle into orbit. Typically such a feat requires speeds reaching 17,500 miles per hour (28,000 kilometers per hour). Starship reached its orbital speed target and did not aim to enter orbit on the third flight.
Starship’s payload door, a hatch that must be opened for the spacecraft to deploy satellites into space after reaching orbit, was opened before being resealed in a key test of that mechanism.
SpaceX also performed a “propellant transfer demonstration,” meaning it moved some of the propellant from one tank to another on the Starship vehicle. SpaceX engineers designed the demo to test how Starship would be refueled on future missions while in orbit.
However, as Starship re-entered Earth’s atmosphere, the team lost communication with the spacecraft after a halo of bright red plasma created by extreme heat and pressure glowed around the vehicle.
However, SpaceX never considered saving Starship after this flight test.
The Super Heavy booster was also expected to make an autonomous, controlled descent into the ocean, but the booster was lost due to all of its engines failing.
But both the Starship spacecraft and the booster managed to fly farther than the previous two tests in 2023.
Starship’s huge goals
A lot depends on Starship’s ultimate success. SpaceX CEO Elon Musk has repeatedly described the rocket as central to the company’s founding mission: to send humans to Mars for the first time.
NASA has selected the Starship spacecraft to play a key role in the Artemis program to return humans to the moon for the first time in more than fifty years. According to the federal space agency’s current road map, Starship will complete the final leg of a crewed mission that will pick up astronauts from a spacecraft in lunar orbit and carry them to the surface. The United States is racing with China to be the first to develop a permanent lunar outpost and set a precedent for deep space settlements.
Milestones such as propellant transfer from the third flight test targets for the future. Replenishing the spacecraft’s fuel will be critical for Starship’s future high-profile missions.
Once Starship travels to the moon under the supervision of Artemis, it will need to sit in a near-Earth orbit as SpaceX launches separate boosters that will carry fuel to the spacecraft. To reach the moon, SpaceX may need to make more than a dozen refueling trips.
The first astronaut landing under the Artemis program is planned to take place in September 2026.
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