The space agency has an explanation for the premature shutdown, saying everything’s swell, but a second test remains a distinct possibility.

The first hotfire test of the Space Launch System (SLS), performed on Saturday, January 16 at NASA’s Stennis Space Center in Mississippi, came to a grinding halt at just over the one-minute mark when a key parameter went into out-of-bounds territory, explained NASA in a statement.

With the 212-foot-tall (65-meter) rocket stage anchored to the B-2 test stand, and with the core stage filled with more than 700,000 gallons of propellant, the engines sprung to action at 5:27 p.m.

NASA has reviewed the data and done preliminary inspections of the system, finding that the rocket’s hardware is in “excellent condition” and that the shutdown “was triggered by test parameters that were intentionally conservative to ensure the safety of the core stage during the test.”.

It consists of a core stage with four RS-25 engines, along with two smaller solid rocket boosters attached to each side à la the Space Shuttle Program.

The gimbaling of the engines worked as planned, but the associated hydraulic system “exceeded the pre-set test limits that had been established,” resulting in the shutdown, according to NASA.

“The data is being assessed as part of the process of finalizing the pre-set test limits prior to the next usage of the core stage.”.

In terms of positives, it was the second successful wet test (i.e., the rocket was fully loaded with propellant), the team was able to pressurize the propellant tanks, and they completed a countdown leading to the ignition of the engines.

As reported in SpaceFlightNow, John Shannon, SLS program manager at Boeing, said the team wanted to acquire and evaluate at least 250 seconds of data during the test before proceeding to the next stage.

Obviously, a full eight-minute test would be even better, as that’s the total length of time it will take the SLS rocket to reach space.