rehearsal

Feb. 3 (UPI) — NASA early Tuesday announced it was pushing the launch date of its Artemis II mission to March, after engineers encountered a liquid hydrogen leak during a critical prelaunch test.

“With the conclusion of the wet dress rehearsal today, we are moving off the February launch window and targeting March for the earliest possible launch of Artemis II,” NASA Administrator Jared Isaacman said in a statement.

The announcement followed the completion of a two-day test called a wet dress rehearsal of its planned lunar flyby at Launch Complex 39B at NASA’s Kennedy Space Center in Florida, which involved Mission Control at the Johnson Space Center in Houston.

NASA had initially aimed to launch Artemis II in a Feb. 8-11 window.

Moving the mission’s launch window will give teams time to review data and conduct a second wet dress rehearsal, NASA said in a separate statement.

“Moving off a February launch window also means the Artemis II astronauts will be released from quarantine, which they entered in Houston on Jan. 21,” it said.

NASA began the 49-hour countdown of the wet dress rehearsal at 8:13 p.m. EST Saturday. The test included the loading of cryogenic propellant into the Space Launch System tanks, sending a team out to the launch pad to close out the Orion spacecraft and safely draining the rocket, among other maneuvers.

Officials said that a liquid hydrogen leak occurred during tanking, and that engineers spent several hours troubleshooting the issue.

By allowing the interface to warm up so seals could reseat and by adjusting propellant flow, teams were able to successfully fill all tanks in both the core stage and interim cryogenic propulsion stage, they said.

The countdown reached about T-5 minutes when a spike in the liquid hydrogen leak rate automatically stopped the countdown sequencer.

“With more than three years between SLS launches, we fully anticipated encountering challenges,” Isaacman said. “That is precisely why we conduct a wet dress rehearsal. These tests are designed to surface issues before flight and set up launch day with the highest probability of success.”

“This is just the beginning,” Isaacman added.

The Artemis I mission in 2022 was a successful uncrewed launch of NASA’s new rocket and spacecraft system. The mission flew around the moon.

The Artemis II seeks to do the same mission but with astronauts. It will carry the first crewed lunar flyby in more than 50 years.

NASA’s Space Launch System rocket, with the Orion spacecraft perched on top, stands on Complex 39B early Sunday at the Kennedy Space Center in Florida as a wet dress rehearsal for the Artemis II mission around the moon gets started. The mission will launch no earlier than February 8. Photo by Joe Marino/UPI | License Photo

Feb. 1 (UPI) — After adjusting its timeline for the last remaining tests of the Artemis II space launch system and Orion capsule because of freezing cold temperatures in Florida, NASA is now pressing ahead in preparation for its launch to the moon.

NASA had planned to start the fueling phase of the wet dress rehearsal for the rocket’s launch cadence on Saturday night, but a blast of Arctic air reached all the way down to Kennedy Space Center in Florida making it too cold to load propellants into the ship’s fuel tanks.

As a result, the fueling tests were pushed back to Monday — and launch will now happen no earlier than Feb. 8 — as the agency held off on powering up the SLS rocket’s core stage until Sunday morning.

“NASA continues to press ahead through the countdown for the Artemis II wet dress rehearsal,” NASA said in a statement. “Teams monitored all systems throughout the overnight hours [Saturday] during cold temperatures and high winds.”

The wet dress rehearsal is a test of the full launch team and the series of complex steps involved in a space launch, which includes engineers in Florida, at Mission Control at Johnson Space Center in Houston and at other NASA facilities.

The tanking phase of the wet dress rehearsal involves loading more than 700,000 gallons of liquid oxygen and liquid hydrogen, as will happen before the actual launch.

The test involves filling, topping off and replenishing the tanks over a series of loading milestones.

Engineers also will start preparing to charge the Orion space capsule’s flight batteries and the core stage battery, in addition finishing preparations of the umbilical arms and a walk down at the launch pad, NASA said.

Tanking operations require an overall outdoor temperature above 41 degrees, and cannot dip below 40 for more than 30 consecutive minutes, during both the rehearsal and actual launch.

The full wet dress rehearsal is a complete countdown simulation — the wet dress countdown started Sunday at minus-39 hours and 30 minutes — and will end with a simulated launch window on Monday around 9:00 p.m. EST, NASA said.

Artemis II’s launch window is currently set for Feb. 8 to Feb. 11, but NASA has previously said that if the rocket is not ready to launch next week that additional launch windows in March and April have been identified.

Jan. 30 (UPI) — Frigid temperatures have delayed NASA’s preparations for its wet dress rehearsal for the Artemis II launch, the space agency announced Friday.

NASA was expected to begin the tanking operation Saturday night in preparation for a possible Feb. 6 or Feb. 7 launch date, but those “are no longer viable opportunities,” a release said.

The agency now expects to set Monday as the tanking day with an earliest possible launch set for Feb. 8 at the Kennedy Space Center in Cape Canaveral, Fla.

Tanking operations involve loading propellants into a fuel tank near the launch pad. The outdoor temperature plays a crucial role in that process — it can’t be below 40 degrees Fahrenheit for more than 30 consecutive minutes. The overall average temperature must be above 41 degrees for the rehearsal and launch, WESH-TV in Orlando, Fla., reported.

AccuWeather forecasters said temperatures were expected to plummet this weekend to levels not seen since 1966 in some areas. Temperatures between 20 degrees to 30 degrees were expected Sunday morning in Cape Canaveral.

“Adjusting the timeline for the rest will position NASA for success during the rehearsal, as the expected weather this weekend would violate launch conditions,” a release from NASA said.

In the meantime, the Artemis II crew members are expected to stay in quarantine in Houston. The crew includes Reid Wiseman, commander; Victor Glover, pilot; Christina Koch, mission specialist; and the Canadian Space Agency’s Jeremy Hansen, mission specialist.

Artemis II is NASA’s first crewed mission aboard its deep space rocket, the Space Launch System, and Orion spacecraft. It’s the second flight of the SLS and the first crewed mission near the moon since 1972.

Over 10 days, Artemis II will travel around the moon and back to Earth as the crew tests whether the spacecraft operates as it should in deep space. The long-term goal of the Artemis program is reestablish a human presence on the moon in preparation for the ultimate aim of putting a human on Mars.

NASA has shared a live stream of the launch pad on YouTube as it prepares for the wet dress rehearsal launch.