NASA Targets Late September For Next Artemis I Launch Attempt

NASA is targeting September 23 or September 27 for the next attempt to launch Artemis I, but those dates are quite tentative. Not only does NASA need to get a waiver from the U.S. Space Force to avoid replacing a critical battery for the Flight Termination System, but also must successfully test new seals being installed to fix the liquid hydrogen leak that scrubbed Saturday’s launch.

Artemis is NASA’s program to land astronauts on the Moon for the first time since the last Apollo crew left in 1972. Artemis is the twin sister of Apollo in Greek mythology. NASA intends to put the first woman on the Moon, as well as the first person of color.

Artemis I is an uncrewed test flight of NASA’s new Saturn V-class rocket, the Space Launch System (SLS), and Orion spacecraft. NASA plans a test flight with a crew, Artemis II, in 2024. Astronauts would return to the lunar surface on the Artemis III mission a year later under NASA’s current schedule.

But Artemis I is the first step. The first launch attempt on August 29 was called off when a sensor indicated one of the four engines was not chilled sufficiently. The sensor was determined to be faulty. A second try on September 3 was scrubbed due to a liquid hydrogen (LH2) leak in an 8-inch Quick Disconnect (QD) fitting for the LH2 fill and drain line for the Core Stage. The rocket is connected to ground systems by a number of umbilicals on the Mobile Launcher. QDs instantly disconnect them at the moment of launch.

Jim Free, the head of NASA’s Exploration Systems Development Mission Directorate, told reporters this morning that the agency has requested September 23 and 27 from the U.S. Space Force’s Eastern Range for the next two possible launch attempts.

All the launch pads at NASA’s Kennedy Space Center and the adjacent Cape Canaveral Space Force Station are controlled by the Range. The Space Force’s Space Launch Delta 45, commanded by Brig. Gen. Stephen Purdy, Jr., oversees all activity including scheduling launches and ensuring public safety.

NASA is requesting a waiver from the Range’s requirement to test or replace a critical battery for the Flight Termination System (FTS) that the Range would use to destroy the rocket if it veers off course. The battery is supposed to be tested or replaced after 20 days, but can only be accessed in the Vehicle Assembly Building when the 322-foot tall rocket is surrounded by work platforms, not at the launch pad. The FTS system has components in the Core Stage, the Interim Cryogenic Upper Stage, and the two Solid Rocket Boosters, but the Core Stage is the “heart” of the system and that is the battery under discussion.

The launch pad and the VAB are about four miles apart and it takes 8-12 hours to move the rocket from one place to the other atop the Crawler-Transporter.

NASA wants to do that as few times as possible to avoid any possible damage to the rocket. It already received a waiver extending the period to 25 days to cover the first set of launch opportunities in late August and early September, but this would be several weeks beyond that.

Free went out of his way today to praise the Range and its commitment to public safety, offering assurances that NASA will comply with whatever decision it makes.

NASA is trying to schedule the launch in between two other NASA missions.

On September 26, the Double Asteroid Redirection Test (DART) spacecraft will impact Dimorphos, the tiny moon of an asteroid named Didymos, to test a method of deflecting asteroids that might threaten Earth. DART needs NASA’s Deep Space Network to communicate back to Earth, but Artemis I’s Orion spacecraft, which will travel around the Moon, also needs DSN. On October 3, NASA will launch a new crew to the International Space Station from the launch pad next to Artemis’s and pre-launch preparations need to be taken into account. That left September 23 and 27 as possible launch dates in this upcoming launch period 26.

They are quite tentative, however. Not only does NASA need to get the waiver from the Range for the FTS battery, but it has to finish replacing the seal in the 8-inch QD. They are replacing one in a 4-inch QD as well. They are doing that work at the pad so they can run cryogenic propellant through the lines as a test, which can only be done at the pad.

NASA is targeting September 17 for the test, but Mike Bolger, NASA’s Exploration Ground Systems program manager, said he wouldn’t be surprised if that slipped a day or two. He added that they need at least four days between the test and launch. That means it would have to be done by September 19 for a September 23 launch.

As of this morning, engineers have taken an initial look at the seals. The 8-inch has a “minor notch” that they will be “taking a lot deeper look at,” but they “didn’t see much” on the 4-inch.

On Saturday, Artemis Mission Manager Mike Sarafin said the hydrogen leak might have been caused by an “inadvertent” overpressurization of the hydrogen transfer line during a manual operation.

Today, Bolger said they are still evaluating whether that caused the leak, but the management team has apologized to the individual who made the error because it was a last-minute change and not enough time was provided to practice the new procedure, which ordinarily is automated. Free added that “we all own the process. … Everybody’s finger was on that switch.”

For the future, Bolger said they will adopt a “kinder, gentler approach” to fueling and hopefully avoid problems that arose during both launch attempts.

Artemis I can only launch at certain times due to the alignment of the Moon and Earth and test requirements such as splashing down in daylight. When it launches determines whether it is a “short” or “long” mission of either 26-28 days or 38-42 days.

If it launches on September 23, the two-hour launch window opens at 6:47 am ET and Orion would return on October 18.

If it launches on September 27, the 70-minute launch window opens at 11:37 am ET and Orion would return on November 5.

The next two launch periods, 26 (September 19-October 4) and 27 (October 17-31), are shown in this NASA table.

A graphic of additional launch opportunities through the first half of next year are posted on NASA’s website, though in less detail and those more than two-months out are subject to refinement.