Nasa halts Moon rocket fueling test for second time in two days

Nasa called a second halt to fuel test of massive Moon rocket on Monday

Nasa was forced to halt a critical fueling test for its new Moon rocket due for the second time in two days.

The space agency began the “wet dress” rehearsal test of the Space Launch System rocket and Orion spacecraft on Friday, but halted the test — which involves pumping the rocket full of liquid oxygen and liquid hydrogen fuel — on Sunday due to the failure of two fans needed to prevent the leakage of flammable gasses.

With the rocket still on the launchpad at Cape Canaveral, Florida, Nasa gave the go-ahead to resume the wet dress rehearsal and fueling Monday morning, but stopped the process again around 5pm (EST) after a problem with a panel controlling a pressure relief valve governing pressure inside the core stage of the SLS rocket during fueling. The ground team had loaded around half of the liquid oxygen called for into the core stage at the time the process was halted.

Nasa will hold a press conference on Tuesday to address the issues with the test so far and the path forward to complete the testing.

The wet dress rehearsal is meant to uncover the types of issues that can crop up when pumping actual cryogenic fuel into a rocket on the launchpad, and according to a Nasa blog, the ground team worked on the fly Monday to develop a new procedure for loading liquid oxygen into the rocket to avoid problems.

Once the test resumes, Nasa will practice a launch countdown and then defuel the rocket, which will be returned to the Vehicle Assembly Building at Kennedy Space Center for a final workover before an upcoming test flight.

SLS and Orion are the cornerstones of Nasa’s Artemis program, which aims to return humans to the Moon in 2025. The first mission of the program, Artemis I, will be an uncrewed test flight of SLS and Orion, and could launch as early as May.

A crewed lunar flyby mission, Artemis II, will follow in May 2024, and Artemis III, in 2025, will land two astronauts on the lunar surface.

But the exact schedule for launching Artemis I, and therefore the rest of the Artemis program, rests on the results of the wet dress rehearsal and any problems it uncovers, and the solutions Nasa can provide for them.