NASA will remove the space launch system rocket from the launch pad for maintenance

On April 17,local time,NASA announced that it would evacuate the space launch system(SLS)rocket on launch pad 39B of Kennedy Space Center in Florida and return it to the rocket assembly building for various maintenance,and held a telephone meeting to discuss the next launch drill test of SLS rocket and Orion spacecraft.This also means that the first flight of the SLS rocket will be further postponed.
NASA said that because the gaseous nitrogen supplier used for the test needs to be upgraded,NASA will take this opportunity to transport the SLS rocket and Orion spacecraft back to the rocket assembly building,replace the faulty upper stage check valve,and repair the leakage of liquid hydrogen.During this period,NASA will review the schedule of demonstrating propellant filling operations before rocket launch.
The SLS rocket being developed by NASA can launch a 95 ton payload into low earth orbit.The initial configuration of SLS can send payloads of more than 27 tons into lunar orbit,and the future upgraded version will enable the rocket to deliver at least 46 tons.Once developed,SLS allows astronauts to begin exploring destinations deep in the solar system.
The SLS rocket and the Orion spacecraft on top are about 98 meters high.It took about 10 and a half hours to move from the rocket assembly building to the launch pad 39B of Kennedy Space Center 6.4 kilometers away in mid March.NASA originally planned to conduct wet dress rehearsal tests from April 1 to 3 local time,including filling propellant into the rocket tank and implementing a complete launch countdown.This is also the last important test before the launch of the"Artemis I"unmanned lunar mission.
However,the test process is full of twists and turns.So far,the countdown test has not been completed in three attempts,and it is uncertain when the liquid hydrogen leakage can be solved.On April 14 local time,NASA detected liquid hydrogen leakage shortly after filling the core stage of the rocket with liquid hydrogen.However,the leak is not in the SLS rocket itself,but at the bottom of the mobile launcher and connected to the core stage of the rocket.As a result,the test could not be completed.When the team suspended the filling of propellant,the liquid oxygen tank of the core stage of the rocket was filled with 49%,and the liquid hydrogen tank had been filled with about 5%capacity before the leakage of liquid hydrogen.
Previously,the lightning tower near the 39B launch pad was struck by lightning four times in early April.NASA originally tried to fill SLS with propellant on April 3,but it stopped before filling because of the pressurization problem of the mobile launcher.On April 4,the exhaust valve problem of ground equipment hindered NASA's second rocket propellant filling attempt.NASA canceled the SLS rocket drill test originally planned for that day,and the faulty exhaust valve was used to release the pressure of the core stage of the rocket during the propellant filling process.
NASA plans to send the first woman and the first colored man to the moon surface through the Artemis mission,paving the way for a long-term stay on the moon and access to Mars.Among them,the"Artemis I"mission will provide the foundation for human deep space exploration and demonstrate the ability to expand human beings to the moon and beyond before the manned first flight of"Artemis II".