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After two nail-biting and explosive test flights in 2023, the SpaceX Starship rocket is back on the launch pad at the Starbase facility in Boca Chica, Texas.
The deep space rocket system aims to make it through a one-hour integrated flight test. If successful, the spacecraft will splash down in the Indian Ocean, enabling the gargantuan vehicle to move on to more complex test flights and, eventually, carry NASA astronauts to the surface of the moon.
The launch could take place at any time during a 110-minute window that opens at 7 a.m. CT (8 a.m. ET) Thursday, according to an email from SpaceX sent Wednesday afternoon. The event will begin streaming live on the company’s website approximately 30 minutes before the expected takeoff.
SpaceX considers the Starship system critical to its original mission: to transport humans to Mars for the first time. And crucially, NASA has chosen Starship as the landing vehicle that will send its astronauts to the lunar surface on the Artemis III mission which is planned to take off as early as September 2026.
If all goes as planned during Thursday’s test flight, the Super Heavy booster — the first stage, or lower part, of the launch vehicle — will roar to life and soar over the Gulf of Mexico.
Almost three minutes into the flight, the Super Heavy booster will burn through most of its fuel and break out of the Starship spacecraft, the upper stage riding on top of the Super Heavy.
The booster will then aim to make an autonomous, controlled landing in the ocean, while the Starship spacecraft uses its own engines to continue driving to breakneck speeds.
Focused on orbital speeds
SpaceX CEO Elon Musk has said that the main goal of these early test flights is to get Starship up to orbital speeds – speeds fast enough to allow the spacecraft to enter a stable orbit around Earth.
Typically, such a feat requires speeds in excess of 17,500 miles per hour (28,000 kilometers per hour).
A starship, however, will not aim to enter orbit on this flight. Instead, the spacecraft will make a hard landing in the Indian Ocean — hopefully more than 230 miles (370 kilometers) from the nearest land mass, according to documents published by the Federal Aviation Administration, which authorizes commercial rocket launches.
Starship tests and technology demonstrations
A starship will have to burn its engine for six minutes before entering coast phase. The spacecraft will then run through several important tests and technology demonstrations.
First, Starship will attempt to open its payload door – a mechanism that the capsule will need to swing in order to deploy the satellites into space on future missions.
Next, SpaceX will perform what the company is calling a “propellant transfer demonstration.” The goal is to move part of the propellant aboard the Starship vehicle from one tank to another, according to a December email from NASA explaining the test.
SpaceX engineers designed that demo to begin hashing out how Starship will be refueled on future missions while in orbit.
NASA Artemis moon mission
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 NASA’s Artemis program – it will have to sit in a near-Earth orbit while SpaceX sends separate vehicles that will only carry fuel to the spacecraft. To get to the moon, SpaceX may have 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, the Starship vehicle will attempt to restart its massive engines before falling back towards the ocean.
SpaceX’s explosive test-flight process
Musk said he is more confident that this flight will be successful compared to the 2023 efforts. Success could provide the company with critical data that could allow Starship to move on to more difficult test flights.
“I don’t want to jinx it, but I think the probability of it reaching orbit is good – 80%,” he said during a recent speech posted on social media . “The third flight is definitely a much better rocket than one or two flights.”
Still, SpaceX officials have repeatedly said that the company is not expecting 100% accuracy on these early test flights.
“All of these flight tests are always just that: a test. They’re not happening in a lab or on a test stand, but they’re putting flight hardware in a flight environment to maximize learning,” the company said in a statement posted on its website. “This rapid, iterative development approach has been the basis of SpaceX’s major innovative breakthroughs.”
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