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After two exciting and explosive test flights in 2023, the SpaceX Starship rocket has returned to the launch pad of the Starbase facility in Boca Chica, Texas.
The deep space rocket system aims to undergo a one-hour integrated flight test. If successful, the spacecraft will land in the Indian Ocean, putting the massive craft in a position to move on to more complex test flights and eventually carry NASA astronauts to the surface of the moon.
The launch could happen any time during a 110-minute window that will open at 7 a.m. CT (8 a.m. ET) on Thursday, according to an email SpaceX sent Wednesday afternoon. The event will begin streaming live on the company’s website approximately 30 minutes before the highly anticipated departure.
SpaceX thinks the Starship system is crucial to its founding mission: carrying humans to Mars for the first time. And more importantly, NASA has chosen Starship as the lander that will carry its astronauts to the lunar surface on the Artemis III mission, which is scheduled to launch in September 2026.
If all goes as planned during Thursday’s test flight, the Super Heavy booster (the first stage or bottom part of the launch vehicle) will come to life and fly over the Gulf of Mexico.
About three minutes into the flight, the Super Heavy booster will burn up most of its fuel and the upper stage, which sits atop the Super Heavy, will break away from the Starship spacecraft.
The thruster will then aim for an autonomous, controlled descent into the ocean, while the Starship spacecraft will continue to reach dizzying speeds using its own engines.
Targeting orbital velocities
SpaceX CEO Elon Musk has said that the primary goal of these early test flights is to get Starship to orbital speeds, that is, speeds fast enough to allow the spacecraft to enter a stable orbit around Earth.
Typically such a feat requires speeds reaching 17,500 miles per hour (28,000 kilometers per hour).
However, Starship will not actually aim to enter orbit on this flight. Instead, according to documents released by the Federal Aviation Administration, which allows commercial rocket launches, the spacecraft will make a hard landing in the Indian Ocean; hopefully it will be 230 miles (370 kilometers) from the nearest land mass.
Starship tests and technology demos
Starship will have to burn its engine for about six minutes before moving into the docking phase. The spacecraft will then undergo several important tests and technical demonstrations.
Starship will first attempt to open the payload door, which must remain ajar for the capsule to deploy satellites into space on future missions.
Then, SpaceX will also perform what the company calls a “propellant transfer demonstration.” The goal is to move some of the propellant on the Starship vehicle from one tank to another, according to NASA’s December email announcing the test.
SpaceX engineers designed this demo to understand how Starship will be refueled while in orbit on future missions.
NASA Artemis moon mission
Replenishing the spacecraft’s fuel will be critical for Starship’s future high-profile missions.
When Starship travels to the moon as part of NASA’s Artemis program, it will need to sit in a near-Earth orbit because SpaceX will launch separate vehicles that will only carry fuel to the spacecraft. To reach the moon, SpaceX may need to make more than a dozen refueling trips.
SpaceX received approval from regulators on Wednesday to conduct this latest test flight.
About 40 minutes into the flight, Starship will attempt to restart its massive engines one more time before diving toward the ocean.
SpaceX’s explosive test flight process
Musk said he was more confident that this flight would be successful compared to the trials in 2023. Success would potentially provide the company with important data that could allow Starship to move on to more challenging test flights.
“I don’t want to jinx it, but I think the probability of reaching orbit is good – 80%,” he said in a recent speech posted on social media. “Definitely the third flight is a much better rocket than one or two flights.”
Still, SpaceX officials have repeatedly said the company does not expect 100% accuracy in these early test flights.
“Each of these flight tests continues to be just that: a test. “These do not take place in a laboratory or test stand, but they put flight hardware into the flight environment to maximize learning,” the company said in a statement posted on its website. “The rapid, iterative development approach has underpinned all of SpaceX’s major innovative advances.”
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