SpaceX has completed a largely successful fourth test of its revolutionary new Starship rocket, a key step toward returning humans to the Moon and, perhaps one day, landing on Mars.
The flight, Integrated Flight Test 4 (IFT-4), took off today from SpaceX’s Boca Chica test site in Texas at 7:50 a.m. Central Time. Standing 71 meters (233 feet) tall, the rocket and its 33 methane-fueled Raptor engines sprang to life, lifting Starship, the largest rocket in history, into the sky over the Gulf of Mexico from the test site, called Starbase.
“Today’s test was the clearest success to date,” says Abhi Tripathi, former mission manager at SpaceX and now an aerospace engineer at UC Berkeley’s Space Sciences Laboratory. “It was incredible.”
Although one of the engines failed (Starship is designed with redundancy in case of engine failures in mind), the rocket’s trip to space went smoothly. This was the third time a Starship vehicle reached space and the second time it reached suborbit, the other being the final test flight, IFT-3, in March.
Starship is made up of two parts, a lower section known as the Super Heavy booster and the upper section, Starship itself, which will one day host up to 100 humans on trips to the Moon and Mars. Three minutes into today’s flight, at an altitude of about 48 miles (78 kilometers), the two sections separated as planned, and Super Heavy began its journey back to Earth.
Once Starship is fully operational, the goal is for each Super Heavy booster (and Starship) to land back at the launch site, where they will be caught by giant “chopsticks” on the launch tower, ready for another flight. However, before SpaceX feels comfortable trying this, it wants to prove that Super Heavy can return to Earth safely. So one of the key objectives of today’s test was for the booster to descend into the Gulf of Mexico, restart 13 of its engines, and land softly.
That test was passed without problems for the first time, and the booster fell seven and a half minutes into the mission. “That booster landing in the ocean was phenomenal,” says Laura Forczyk, a space consultant and founder of the George-based company Astralytical. “That gives us confidence that SpaceX can make Starship reusable.”
The spacecraft’s journey into space continued, with the vehicle making its way over the Atlantic Ocean, southern Africa and into the Indian Ocean, reaching a maximum altitude of 132 miles (half the orbital height of the International Space Station). approximately 24 minutes into your flight. .
From here it began its own journey back into the Earth’s atmosphere, in an attempt to also perform a vertical test landing in the ocean. However, this task is much more difficult for Starship; Traveling at about 17,000 miles per hour, the vehicle must contend with temperatures of 2,600 degrees Fahrenheit (1,400 degrees Celsius) when it reaches the atmosphere.
The underside of the spacecraft is lined with thermal plates to displace this heat, but on Starship’s final test flight in March, the vehicle broke up at an altitude of about 40 miles due to the intensity of reentry. This time SpaceX hoped to reach the ocean, and two of the tiles were also removed to see how the vehicle would cope with the high temperatures.
