A countdown ticks for some components of the Artemis I rocket, still on the ground. The Space Launch System boosters will expire in December 2022, if the mission has still not gone to the Moon.
The first mission of the ambitious Artemis program is still grounded. The Space Launch System (SLS) rocket was supposed to fly to the Moon in the summer of 2022, but several hazards, including liquid hydrogen leaks, prompted NASA to postpone takeoff on numerous occasions. The weather doesn’t help either: rockets are much more sensitive to it than planes. Due to an ominous storm, Artemis I is currently not scheduled to depart until November 16.
These long months of waiting are not without consequences for the equipment. As Space spotted on Nov. 9, the rocket’s boosters have an expiration date. The rocket is equipped with two imposing boosters, approximately 53 meters high, intended to provide 75% of the total thrust at takeoff. However, if the mission has still not taken off in mid-December, it is likely that NASA will have to reanalyze this equipment. It will be necessary to ensure that they can still be used on takeoff, after their expiry date.
Artemis I boosters expire on December 9 and then on December 14
This information was transmitted on November 3, during a NASA press conference, which can be listened to again on YouTube. The experts explained there that, as soon as the pieces of a rocket begin to be stacked, a countdown begins for the validity of the elements. Initially, the deadline was 12 months for boosters, then it was revised to 23 months. However, this deadline is soon coming to an end. “One piece expires on December 9 of this year and the other on December 14 of this year,” said Cliff Lanham. He is the principal responsible for vehicle operations for the Exploration Ground System, one of three programs at Kennedy Space Center in Florida.
Remember that the Artemis I mission cannot be launched every day. In addition to the weather or the state of the launcher, NASA must consider other parameters to know when to launch the SLS. The positions of the stars must be taken into account for the mission to be feasible. Since the objective is to send the Orion capsule around the Moon, we consider the Earth-Moon alignment. So there is a calendar with the possible launch periods.
The table below contains the remaining dates for November and December. Take-off is only possible on days in green (in light green, the mission will be shorter than in dark green). Thus, we see that there are few possibilities left until the first booster expires on December 9: Artemis I can take off from November 16 to 19, then from November 22 to 25, and finally on November 27.
NASA can launch Artemis I on dark green and light green dates. Source: Nasa screenshot
Things could even get even more complex, if ever NASA were to abort the November 16 takeoff attempt, while the main stage tanks are supplied. Such a situation has already arisen for Artemis I. It is, therefore, necessary to respect other instructions: no more than 3 launch attempts in 7 days, minimum of 48 hours between attempts n° 1 and n° 2, minimum of 72 hours between attempts n° 2 and n° 3.
We are not there yet, but all this shows that the imminent departure of Artemis I for the Moon is not yet won. No criterion is left to chance: it is a mission of 4.1 billion dollars that is at stake on this launch pad at the Kennedy Space Center.