Artemis I Launch on a Moon Trip Saturday

On Saturday, we’ll try again to launch the unmanned Artemis I mission on its circumlunar journey around the moon.

On September 3 at 2:17 p.m. ET, the start of the launch window opens.
The launch crew spent the rest of Monday reviewing data collected before the mission was halted. Managers provided an update on the mission on Tuesday night.

Artemis I Launch on a Moon Trip Saturday
Artemis I Launch on a Moon Trip Saturday

On Launchpad 39B at Florida’s Kennedy Space Center, the Space Launch System rocket and Orion spacecraft that make up the Artemis I stack remain still.
Engine 3, one of the rocket’s four RS-25 engines, did not achieve the acceptable temperature range for ignition during takeoff.

Thermal conditioning of the engines is required before to the injection of supercold propellant, which is necessary for takeoff. The launch controllers pump more liquid hydrogen into the core stage’s tank in order to keep the engines from being subjected to sudden temperature changes. A “bleed” describes this condition.
Approximately 423 degrees below zero is the melting point of liquid hydrogen (minus 252 degrees Celsius).

John Honeycutt, manager of NASA’s Space Launch System Program at Alabama’s Marshall Space Flight Center, indicated that Engine #3 was probably 30 to 40 degrees warmer than the other engines, which reached about minus 410 degrees Fahrenheit (minus 245 degrees Fahrenheit).
In the opinion of the mission’s managers, the issue with engine 3 was not the engine itself but rather the bleed system. According to Honeycutt, the engine’s temperature can be inaccurately reported due to a malfunctioning sensor.

Honeycutt remarked, “The sensor’s behavior is inconsistent with the physics of the circumstance.”
The bleed will start 30–45 minutes earlier in the countdown than it did on Monday, and the engine temperature will be monitored throughout.
Sarafin explained that the team had decided not to launch yesterday because they were unable to thermally condition the engines. “We’ll be in the same position on Saturday”.

As stated by Charlie Blackwell-Thompson, Artemis launch director for NASA’s Exploration Ground Systems Program, removing and replacing the sensor at the launchpad would be difficult, thus the only option is to roll it back into the Vehicle Assembly Building for service.
Storms, a faulty 8-inch line used to fill and drain liquid hydrogen from the rocket core stage, and a leaking vent valve on the core stage’s intertank all contributed to the failure to launch during Monday morning’s two-hour launch window.
Options were discussed, and “option one,” in which the loading technique is altered and the engine cool down is initiated earlier, was chosen by consensus. “We also agreed to undertake some work at the pad to repair the leak that we detected at the hydrogen tail service mask umbilical,” stated Mike Sarafin, Artemis mission manager, NASA Headquarters.

According to meteorologist Mark Burger, launch weather officer of the US Space Force’s 45th Weather Squadron, the launch crew will be keeping a careful eye on the forecast for Saturday, as there is a potential of showers and thunderstorms in the morning and early afternoon.
According to Berger, the chances of a launch window weather violation are 60%.

The Artemis I mission still has a backup launch window of September 5.
The Artemis I mission is the first step in a larger program that hopes to send humans back to the moon and then send crewed flights to Mars.