Countdown clocks began ticking Saturday for the maiden launch of NASA’s new Space Launch System rocket Monday on a long-awaited mission to send an unpiloted Orion crew capsule around the moon and back. Charlie Blackwell-Thompson, NASA’s first female launch director, called her team to their stations in Firing Room 1 at the Kennedy Space Center and began the carefully scripted 46-hour, 10-minute countdown at 10:23 a.m. EDT.
Working by remote control, engineers plan to start pumping 750,000 gallons of liquid oxygen and hydrogen fuel into the giant SLS rocket’s core stage just after 12 a.m. Monday, setting the stage for blastoff at 8:33 a.m., the opening of a two-hour window. Forecasters are predicting a 70% chance of good weather.
One question mark going into the countdown is the status of a 4-inch liquid hydrogen quick-disconnect fitting that leaked during a practice countdown and fueling test June 20.
The fitting was repaired after the rocket was hauled back to NASA’s assembly building. But hydrogen leaks typically don’t show up unless the equipment is exposed to cryogenic temperatures — in this case, minus 423 degrees Fahrenheit — and that won’t happen until fueling is underway Monday morning.
If a leak is detected that violates safety standards, launch will be scrubbed. But Blackwell-Thompson says she’s confident the fitting with work normally.
“You don’t really get the full test until you do it at cryogenic conditions,” she said in an interview. “So we believe that we have done everything to correct this issue, and certainly on launch day, as part of our loading, we will know for certain.”
Getting the $4.1 billion SLS rocket off the pad and into space will mark a major milestone for NASA and its Artemis program, which aims to put the first woman and the next man on the moon in the 2025-26 timeframe.
The primary goals of the 42-day Artemis 1 mission are to verify the giant SLS rocket’s performance, to put the Orion crew capsule through its paces and to bring it safely back to Earth, making sure the capsule’s 16.5-foot-wide heat shield can protect returning astronauts from the high-speed heat of reentry.
An instrumented, spacesuited mannequin — Moonikin Campos — and two artificial female torsos will help scientists measure the radiation environment of deep space, along with the vibrations, sound levels, accelerations, temperatures and pressures in the crew cabin throughout the mission.
If the flight goes well, NASA will press ahead with plans to launch four real astronauts on a looping free-return trajectory around the moon in late 2024, followed by a mission to land two astronauts near the moon’s south pole as early as 2025.
That flight will depend in large part on SpaceX’s development of a lander based on the design of its futuristic Starship rocket, but few details on the company’s progress or NASA plans have been released.
