Nasa has delayed the date of its first trip back to the Moon once again.
The Artemis II mission was initially planned to launch as soon as 2019. But it has gone thorough a number of delays in the time since, as a result of issues with the spacecraft that will carry the astronauts around the Moon and then back to Earth.
In recent weeks, the latest of those issues appeared to have been resolved, and the latest date for the Artemis mission was set at the beginning of March. But now yet more delays are required and the mission will not launch until April at the earliest.
The giant moon rocket had been wheeled out to its launchpad and successfully went through a “wet dress rehearsal” that saw it filled with fuel and go through a practice of its countdown.
Now, however, the space agency will be forced to wheel the rocket back to its hangar. That four-mile trip is expected to take place on Tuesday, as long as the weather allows.
The latest problem was related to the rocket’s helium system, engineers said. Helium is required to purge the engines and keep the fuel tanks at the right pressure to ensure that the rocket can safely take off.
"Returning to the Vehicle Assembly Building at Kennedy is required to determine the cause of the issue and fix it," Nasa said in a statement.
A previous attempt to test the rocket had revealed dangerous hydrogen fuel leaks. But, after that discovery, engineers replaced key parts and those problems appeared to be under control, leading the team to set the 6 March launch date.
That in itself was already a month later than the most recent plans.
Nasa said that rolling the rocket back quickly should limit the delay required. But it said that meeting its new timing of April will depend on the success of its repairs.
The three American astronauts and one Canadian colleague were placed into quarantine ahead of the early March launch date and remain on standby at Nasa’s facilities in Houston, Nasa said.
When the mission does finally take off, the team of four will be the first people to fly to the Moon since Nasa’s Apollo programme, the last flight of which saw people land on the Moon in 1972. This time around, the crew will only fly around the far side of the Moon, but they hope it will be followed by a trip that will allow astronauts to set foot on the lunar surface once again.
