SpaceX's giant Starship rocket's fourth test flight, both the booster and Starship successfully landed softly

On Thursday, Eastern Time, the giant Starship rocket under SpaceX was launched from the Starbase spaceport in Boca Chica, Texas, USA, for its fourth flight, ultimately achieving complete success. The test flight was very successful, with all key stages performing perfectly except for some issues with the live broadcast later on. The newly added hot separation ring ejection task was completed smoothly, and the super heavy booster successfully splashed down in the Gulf of Mexico about 10 minutes after launch, marking the first controlled return of the super heavy booster. After 66 minutes of flight, the Starship re-entered the atmosphere. Despite at least one fin being severely damaged and some heat shield tiles falling off during the blackout phase, it ultimately successfully splashed down in the Indian Ocean, achieving the main goal of this test.

This 121-meter-tall rocket ignited and ascended from SpaceX's "Starbase" launch facility in Boca Chica, Texas, at 8:50 am Eastern Time, powered by the 33 Raptor engines of the super heavy booster. It soared into the sky from the Gulf of Mexico coast in a dazzling flame jet, accelerating upwards in an eastward arc.

The super heavy booster was able to generate 16 million pounds of thrust in the early stages of flight, far exceeding the thrust of space shuttles, NASA's Saturn V, and the SLS boosters designed for the Artemis moon rocket, making it the most powerful booster to date.

Despite one Raptor engine shutting down prematurely, the super heavy booster pushed the Starship through the dense lower atmosphere, then separated, flipped, and relit multiple engines, successfully controlled its descent back over the Gulf of Mexico coast, marking the first controlled descent of the super heavy booster. Finally, three engines were reignited for deceleration, successfully splashing down in the water.

Meanwhile, the Starship continued to ascend into space on its own with its six Raptor engines, reaching the planned suborbital altitude and re-entering the atmosphere after orbiting the Earth. In the previous third test flight, the Starship did not survive the friction with the atmosphere and disintegrated in high altitude. This time, the spacecraft remained stable during its return to Earth, surrounded by blazing plasma, with the rocket's belly and control fins engulfed in high temperatures.

During the descent, the camera showed a control fin being eroded by high temperatures, with flame fragments falling off. Although the camera was damaged, data from the Starship continued to flow, leading to a successful reignition of the engines for the planned landing burn. Despite the specific direction of the spacecraft's water landing not being visible from the obviously damaged camera perspective, achieving this was a significant success.

SpaceX spokesperson Dan Huot said, "It's just incredible, I can't wait to see the next flight."

Both the super heavy booster and the Starship are designed for full reusability. Once operational, SpaceX plans for the first-stage spacecraft to return to the launch site and be captured by the giant mechanical arm on the launch stand. The Starship is designed to land at any available location on Earth, the Moon, or even Mars.

SpaceX stated on its website, "The fourth flight test shifts our focus from reaching orbit to demonstrating the return and reusability capabilities of Starship and Super Heavy. The primary objectives are to perform the landing burn and soft landing with the Super Heavy booster and achieve controlled entry of the Starship." In the previous three flights, the Super Heavy booster and Starship stages encountered catastrophic failures before completing all test objectives. However, with each flight, SpaceX implemented hardware and software upgrades, resulting in significantly improved performance.

During the third test flight, the Starship core entered space, orbited the Earth for one lap, and planned to descend over the Indian Ocean but disintegrated in the upper atmosphere. The Super Heavy booster returned to the lower atmosphere over the Gulf of Mexico but lost control.

It is reported that achieving routine flights of the Super Heavy booster and Starship for this mission is crucial for NASA's Artemis lunar program. In 2021, NASA awarded SpaceX a $2.9 billion contract to develop a variant of the Starship to transport astronauts from lunar orbit to the surface and back. Artemis astronauts will use Lockheed Martin's Orion spacecraft to travel to and from the Moon.

To reach the Moon, multiple Super Heavy booster rockets must be launched to robotically refuel the Starship already in low Earth orbit. Subsequently, the Starship lander will fly to lunar orbit to await the astronauts for the lunar landing.

NASA's contract requires an unmanned lunar landing test flight before actual astronaut landings. The previous goal was to conduct the first crewed lunar landing by the end of 2026.

However, analysts believe this will depend on whether SpaceX can launch enough Super Heavy booster Starships to prove their reliability. While SpaceX's concept is frequent flights, learning from mistakes, and flying again, NASA will need a long string of successful flights to deem sending astronauts on the spacecraft as safe.

Below is the live recording of the Starship's fourth test flight:

10:08 Musk confirms X for successful test.

Despite losing many heat shield tiles and one flap damaged, Starship still successfully achieved a soft landing in the ocean!

9:57 SpaceX confirms Starship splashdown successful, live feed shows the ocean surface.

09:48 Starship's flap melted upon reentering the atmosphere.

09:40: Starship re-enters Earth's atmosphere

At 09:28, about 37 minutes into the Starship rocket flight, its camera resumed operation.

At 09:15, Musk posted on X platform that the ground had received signals from the Starship and was investigating the reason for the external camera malfunction.

We did get acquisition signal. 11 internal cameras are transmitting signals. We are trying to figure out why the external camera is not working.

At 08:58, the Super Heavy booster of the Starship rocket successfully landed in the Gulf of Mexico! Unlocking a new milestone!

Musk announced the successful landing of the Super Heavy booster.

At 08:56, the Starship rocket separated from the booster as planned.

At 08:52, the giant Starship rocket under SpaceX was launched from the interstellar base in Boca Chica, Texas, USA for its fourth flight.

Musk announced on X social platform the start of the fourth test flight of the Starship.

The Starship is currently the largest rocket built by humans. When combined with the Super Heavy booster, the height of the entire rocket is close to 120 meters, taller than the Saturn V rocket that carried the Apollo missions to the moon.

Previously, Musk stated on the X platform that the main goal of this Starship test flight is to test the rocket's performance during reentry into the atmosphere, especially to see if the rocket can safely pass through the atmosphere intact during the most intense aerodynamic heating phase.