The Artemis II mission, originally scheduled for launch on February 8, has encountered a delay of at least a month due to a hydrogen leak discovered by NASA during fueling. Similar fuel leakage issues also impacted the first Artemis mission.
Liquid hydrogen and liquid oxygen, the key components of rocket fuel, possess unique properties with extremely low boiling points, making them prone to leaks. These cryogenic liquids, colder than -250 degrees Celsius, require specialized handling equipment to prevent freezing and cracking in the warm Florida environment where rockets are launched.
The exterior of the Space Launch System (SLS) rocket’s core stage is insulated with orange foam to protect the cold fuels from the warm air. Additionally, pre-chilling of fuel lines and tanks is necessary to prevent the fuel from boiling off prematurely. Despite these precautions, the cryogenic fuel’s vapor pressure can lead to leaks, especially with hydrogen, known for its ability to escape through tiny openings.
The recent delay in the Artemis II mission was caused by a leak at the connector between the launch tower hose and the rocket. Engineers aim to resolve this issue at the launch pad to avoid lengthy repairs at the Vehicle Assembly Building, with a new launch target set for no earlier than March 6.
While hydrogen leaks have been a persistent challenge in the space program, NASA continues to use them due to the high thrust-to-weight ratio they provide. In contrast, private companies like SpaceX have shifted to more manageable fuels like kerosene and methane for their rockets.
Critics argue that the SLS rocket’s reliance on liquid hydrogen is costly and unsustainable, as the entire launch system is disposable except for the crew capsule. The future of the SLS rocket hinges on addressing the hydrogen leak issues while considering the economic viability of its operations.
