There have been two scrubbed launch attempts for Artemis 1 and the historic mission is now facing weeks of delays.
This day last week, NASA was set to begin its journey back to the moon with the historic launch of the Artemis 1 mission.
Now, after two scrubbed launch attempts, the space agency is saying that lift off may not happen for another few weeks.
So what went wrong and what will happen next?
What is Artemis 1?
Artemis is NASA’s programme to bring humans back to the moon by 2025 – and bring the first woman and first person of colour.
The uncrewed Artemis 1 mission is the first of several in that plan. It consists of a new rocket – the Space Launch System (SLS) – and the Orion Multi-Purpose Crew Vehicle.
Orion is a reusable, solar-powered craft, capable of carrying up to six astronauts to the moon.
But this reliance on the sun for power means there are some restrictions for when Artemis 1 can launch, as Orion cannot be shadowed from the sun for more than 90 minutes during flight.
NASA set its earliest launch window last Monday (29 August), with additional possible dates over the coming months.
What happened with the launch attempts?
While thousands of people flocked to Florida this day last week to watch the hotly anticipated launch from NASA’s Kennedy Space Center, the attempt was scrubbed following an engine bleed.
Within the two-hour launch window, engineers were unable to find a fix for the temperature issue identified with one of the rocket’s four liquid-fuelled engines, NASA said.
A second attempt was then scheduled for Saturday (3 September). But this too was stood down when engineers could not overcome a leak in the interface between the liquid hydrogen fuel feed line and the SLS.
Three attempts at reseating the seal were unsuccessful and the launch was called off.
#Artemis Update: The team continues to troubleshoot, and plans to return with a variety of options early next week. We are standing down on any launch attempts through the current launch period, which ends Tuesday.
— NASA (@NASA) September 3, 2022
Following the two scrubbed launches, NASA said it is standing down on Artemis 1 launch attempts in early September and reviewing its options.
The agency will likely need to roll the rocket back to the vehicle assembly building at Kennedy Space Center for repairs and to reset the batteries for the flight termination system. This system, required on all rockets for public safety, is used to destroy the rocket in the case of a wayward launch.
The next launch period opens on 19 September, with 14 opportunities in the space of around two weeks. After that, 17 October is set as the beginning of the next launch period.
But with repairs to be done, it is currently uncertain when Artemis 1 will be primed for lift off again. There is expected to be delays of several weeks, with the next launch attempt likely to be in October if the rocket has to return to the vehicle assembly building.
“We don’t launch until it’s right,” Bill Nelson, NASA administrator, said after the first attempt last week.
“It’s just illustrative that this is a very complicated machine, a very complicated system, and all those things have to work. You don’t wanna light the candle until it’s ready to go.”
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