Live coverage: SpaceX to launch its Starship rocket on its fourth test flight

SpaceX is gearing up for its fourth Starship test mission in just over a year, set to launch from its southern Texas facility, Starbase. This mission, known as Flight 4, is a significant step towards achieving the goal of creating a mostly reusable rocket.

Like its predecessors, Flight 4 will be a suborbital flight without a payload. The launch is scheduled for 7:50 a.m. CDT (8:50 a.m. EDT, 1250 UTC) within a 120-minute window. Spaceflight Now and LabPadre will provide live coverage starting at 7:00 a.m. EDT (1100 UTC).

On Wednesday, SpaceX assembled the 121-meter (397-foot) Starship rocket by stacking the Ship upper stage (Ship 29) on top of the Super Heavy Booster (Booster 11). Both components will be expended during the flight, but SpaceX aims to demonstrate their potential for future reuse.

SpaceX founder Elon Musk stated on X (formerly Twitter) that the main objective of this mission is to achieve deeper atmospheric reentry, ideally through maximum heating.

In the previous flight, Flight 3, the upper stage lost control and couldn't restart one of its six Raptor engines. However, the rocket was able to stream high-definition camera views during reentry thanks to its connection to the Starlink satellite network. SpaceX later identified valve clogging as the cause of the roll control failure and has since added additional roll control thrusters and upgraded hardware for improved resilience.

The Super Heavy Booster from Flight 3 also faced issues, shutting down six out of 13 Raptor engines during the boostback burn and failing to perform a landing burn. SpaceX attributed this to filter blockage in the liquid oxygen supply, and future boosters will include enhanced filtration capabilities.

Flight 4 is crucial not only for SpaceX but also for NASA, which plans to use the rocket for the Artemis 3 mission, targeting September 2026. NASA's Human Landing System program, led by Lisa Watson-Morgan, is closely working with SpaceX to develop the rocket that will land astronauts on the Moon.

Watson-Morgan noted that despite some setbacks, significant progress has been made, particularly with the consistency of the Raptor engines. She mentioned that the propellant transfer demonstration, part of a $53.2 million contract with NASA, was a success and is a key step towards future missions.

SpaceX plans to launch multiple missions from more than one launch tower, with a second tower currently being built at Starbase. Additionally, there are plans to expand launch capabilities at NASA's Kennedy Space Center and other sites.

NASA's HLS agreement with SpaceX includes an uncrewed landing of Starship on the Moon before the Artemis 3 mission. Feedback from NASA astronauts is being incorporated into the vehicle's design to ensure it meets the requirements for human spaceflight.

SpaceX aims to shorten the turnaround time between Starship launches, with Flight 4 coming just 84 days after Flight 3. The FAA has approved scenarios for Starship entry that would not require an investigation if the vehicle is lost, potentially allowing for quicker subsequent launches.

With each test flight, SpaceX gains more insights and makes improvements, moving closer to their goal of a reusable, reliable launch system.