NASA's SLS rocket successfully completes hot fire engine test

NASA announced that its core stage of the Space Launch System (SLS) has successfully completed the hot fire test this week at the Stennis Space Center in Mississippi. The four massive RS-25 engines successfully fired for eight minutes 19 seconds, completing the test and reaching a critical milestone ahead of the NASA Artemis I mission. Artemis I will send an uncrewed Orion capsule on a flight around the Moon and back to Earth.

That mission will pave the way for future missions that carry astronauts back to the moon for the first time since the Apollo era. The hot fire test's successful completion marked the cumulation of an eight-part Green Run test campaign for the SLS rocket. NASA says that the team will use data from the test to validate the core design for flight.

The SLS rocket is the most powerful NASA has ever built, and during its test, it generated more than 1.6 million pounds of thrust within seven seconds. NASA describes a successful test as an important milestone in its goal to return humans to the lunar surface and eventually beyond. NASA previously conducted a hot fire test of the SLS core stage on January 16.

However, the four rocket engines only fired for about one minute before the test ended prematurely. NASA has spent the time since that January 16 attempt analyzing data to remedy issues that caused the engines to shut off early the first time. After analyzing the data, the second hot fire test was scheduled to provide researchers with more data to verify the core stage design.

This week's successful test saw all four engines fire for slightly more than eight minutes, which is the length of time the rocket would take during every Artemis launch. The successful hot fire test simulated various operating conditions, including moving four engines in specific patterns to direct thrust and powering engines up to 109 percent power, throttling down, and throttling back up as they would during flight. Next up for the core stage is refurbishment, and then it will be shipped to the Kennedy Space Center in Florida for final assembly.