After years of delays and budget overruns, the American agency is finally preparing to inaugurate the Space Launch System or SLSa launcher designed with the moon in the crosshairs, although other missions remain possible.
NASA is capable
Last April, NASA tried to carry out a countdown test. Due to multiple problems, the SLS had returned to the VAB hangar at the Kennedy Space Center in Florida without the teams being able to completely fill the liquid hydrogen and oxygen tanks (2 million liters at -253 ° C, respectively. 741.941 liters at -183 ° C!).
The 98m-tall launcher returned to its LC-39B launch pad (built for Apollo and previously used for shuttles) in June. This time, the fill was complete, although a leak of hydrogen caused the repetition of the countdown to stop at H-29 seconds when H-10 seconds were targeted. The US agency believes that the difference is not significant and has given the green light to the next step… take off!
The above NASA video was uploaded on June 30th. Its title Artemis I: We Are Capable underlines the agency’s confidence that it sees Artemis I as the most convincing start of its return program to and from the Moon.
Late August, early September … or later
Artemis I it is an uninhabited mission. The SLS will send an Orion capsule to the Moon which will orbit our natural satellite for several days before returning to Earth on Earth.
It is therefore a question of repeating Artemis II which will follow the same scenario with 4 astronauts on board this time (the year 2024 is expected). The European Space Agency (ESA) is a leading partner in the Artemis program and in fact provides NASA with the ESM service module (European service module) of the Orion capsule. Built by Airbus Defense and Space with Thales Alenia Space as subcontractor, this module houses the propulsion, provides electricity and oxygen. In other words, Orion cannot orbit our celestial neighbor without ESA.
Currently, the SLS has returned to the VAB to be prepared for its maiden flight. The earliest possible launch slot, if no technical problems occur, begins August 23 with the following dates (Florida local time for takeoff with the equivalent in metropolitan France).
The launch window specifies, for a given day, the period of time during which the SLS can take off from the indicated time. Depending on the departure date, the mission will be called short (26 to 28 days) or long (38 to 42 days). This means that the Orion capsule will return to Earth after this duration.
If the SLS is not ready for these dates ranging from late August to early September, the position of the Moon in its orbit forces us to wait for another time slot that goes from September 20 to October 4 (except 29/09). Thereafter, each month offers about ten days during which the SLS can take off and send the Orion-ESM duo around our natural satellite.