Why did NASA call off Artemis 1 moon rocket launch?

The first attempt to launch NASA Artemis 1 mission was called off after the crew ‘ran off time’ in the two-hour launch window available on Monday. The mission, hailed as the first step in the next era of human exploration on the moon, was scheduled to take off at 6:03 pm today on 29th August.

The countdown was stopped at T-40 mins after the crew found a technical flaw in one of its engines. T minus (T-time) is used in a launch for particular tasks that must be finished before the rest of the launch can proceed. It shows the time at which the rocket is planned to be launched. So T minus 40 minutes means 40 minutes before the launch.

Why is it called off?

NASA informed that a bleed test to get the RS-25 engines on the bottom of the core stage to the proper temperature range for lift-off was unsuccessful.

Before launch, the engine was to be conditioned i.e. to be bled with liquid hydrogen and oxygen.

This problem can be simply understood as that one of the four main engines could not be properly chilled ahead of its ignition.

Crew came with a troubleshooting plant but could not solve the problem. After the troubleshooting didn’t work, the launch director asked the hydrogen team to come up with a fresh strategy to address the problem.

When will be the next attempt of launch?

NASA has said that the Space Launch System rocket and Orion spacecraft remain in a safe and stable configuration. However, it has not declared the date for the next attempt of launch.

NASA Administrator, Bill Nelson, termed the mission very complicated and emphasised the need to be fully sure before launching. He said that he did ‘not want to light the candle until it’s ready to go’.

Although the next launch window available from NASA is at 12:48 pm ET (10:18 pm as per Indian time) on September 2, it will be clear if they will use this launch window only in the press conference scheduled to be held later tonight.