Planned to be an uncrewed mission around the moon which would pave the way for future human lunar exploration, the launch was set to be the first of Artemis – NASA’s series of increasingly complex missions which hope to enable human exploration to the Moon and Mars.

The launch of the Artemis I, which is set to see the first test of NASA’s Space Launch System (SLS) rocket, Orion spacecraft and ground systems at the Kennedy Space Centre in Florida, US was called off on two occasions, due to two separate liquid hydrogen leaks.

Set to initially take off last Monday (August 29) NASA called off the launch at the 11th hour, after its team struggled to get one of the rocket’s four engines up to the correct temperature required for lift off.

In a press briefing, Jackie McGuiness, Press Secretary for NASA, said, “Earlier in the countdown, teams were able to troubleshoot an issue related to a hydrogen spike while filling the core-stage tanks. The rocket remains in a safe configuration as teams assess the next steps.”

H2 View understands, beyond struggles to solve the leak of liquid hydrogen, the delay left too little time to complete proper preparations ahead of take-off.

Having been rescheduled for lift off for last Saturday (September 3), NASA waived off the launch once again after discovering another hydrogen leak while filling propellent into the core-stage SLS rocket, according to McGuiness in a subsequent press briefing.

It remains unclear when Artemis I will make it off the ground, however NASA has said the last day of its launch window is Tuesday, September 6.

In 2021, Adam Swanger, Principal Investigator at the Cryogenics Test Laboratory at NASA’s Kennedy Space Centre, told H2 View that the space agency has used liquid hydrogen since the early 1960s thanks to its performance.

Read more: The signature fuel of the American space programme: NASA shares why hydrogen plays such a vital role in its missions

Swanger explained, “For rocket propellant, you’re always going to use liquid oxygen, and then you really only have three fuel options – hydrogen, methane or natural gas, and then there’s what we call RP1, which is refined kerosene. Of these three combinations, liquid hydrogen and liquid oxygen is the highest performing one. Once you’re out of the atmosphere and you’re in space, that’s where liquid oxygen and liquid hydrogen really shine from a performance standpoint.”