Although Artemis 1’s rocket and spaceship are still in the shop for another few weeks, NASA has revealed all of the mission’s launch options for 2022. The Artemis 1 moon rocket might launch on July 26 for a round-the-moon mission, though the ESA has mapped out dozens of launch alternatives between then and 22nd December, with many more launch choices to the moon through June 2023.
These dates are based on the Space Launch System passing its wet “dress rehearsal,” which replicates fuelling operations and overcoming the issues that forced the launch pad to be rolled back to the Kennedy Space Center’s VAB (Vehicle Assembly Building) on April 26.
Engineers are working to stop the hydrogen leak which is in the umbilical lines, and they discovered a defective O-ring seal that was replaced on May 13, according to NASA. According to NASA, the full list of options under deliberation on this pathfinder venture to prepare for crewed flights to the moon later in the 2020s is available on their website. All dates after the July 26 to August 10 window are tentative and susceptible to change depending on preliminary examination of the components required to bring the launch to the moon and back.
When the launch dates were announced on May 16, NASA highlighted that “in addition to the deployment opportunities dependent on orbital mechanics and performance criteria, there is also an operational constraint dictated by infrastructure at NASA’s KSC (Kennedy Space Center) facility in Florida.”
The sphere-shaped tanks utilized to store cryogenic fuel at the launch pad can only provide a limited number of launch tries depending on the kind of propellant due to their size, according to the agency. Because of the core stage tanking process, each week has a maximum of three launch attempts.
Engineers must wait 48 hours for a second launch attempt because liquid oxygen and liquid hydrogen are put into the core stage and upper stage on launch day. “Due to the requirement to refill the cryogenic storage sphere with extra propellant from nearby sources,” NASA added, a third attempt will have to wait another 72 hours.
Apart from the fueling operations, NASA identified four major constraints when it relates to determining launch dates. The first is to ensure that the moon is within reach of the upper stage of the enormous SLS rocket, that will perform a trans-lunar injection to propel the Orion spacecraft towards the moon. After that, Orion will fly in a distant retrograde orbit.
The second constraint is that Orion’s solar panels must not be out of the sun for over 90 minutes in order for the spacecraft to function and maintain a safe temperature range. To figure this out properly, orbital dynamicists must take into consideration the positions of the Earth, moon, and sun (all of which exert a gravitational pull on the spaceship), as well as the “state of charge” on the battery.
The third constraint is ensuring that Orion can return to Earth with a “skip entry,” which is only possible on certain launch dates. Orion will use the top part of Earth’s atmosphere, as well as its natural lift, to slow down a little before skipping out of the atmosphere for a little period of time. The spacecraft will then re-enter for the final descent and splashdown.
Finally, Orion must deploy at a time when daylight recovery circumstances are available after splashdown to aid recovery operations. This is especially important after everyone is on board.