NASA has completed a crucial risk assessment ahead of its next lunar flyby mission, and during a press conference the agency revealed a new target launch date and discussed how officials assessed the dangers the mission’s four-person crew will face.
A agency now intends to launch the historic mission, called Artemis II, on April 1st, at 7:24 pm (Brasília time). If there are any delays, there are six additional windows for the launch next month, on April 2nd, 3rd, 4th, 5th, 6th and 30th.
The assessment — known as a Flight Readiness Review (FRR) — took place over two days this week and is a crucial step toward launch, in which mission managers come together to determine whether the rocket, spacecraft and ground systems are ready for launch.
However, John Honeycutt, chairman of the Artemis II Mission Management Team, has not released a specific, quantitative risk estimate for this rocket and spacecraft.
The numbers that characterize the probability of “Mission Loss” or “Crew Loss” are two pieces of data that the agency shared with the public at the time of the Space Shuttle, and similar reviews have been offered for many missions since then. Before an unmanned test flight called Artemis I in 2022, NASA assessed that there was a 1 in 125 chance that the Orion spacecraft — the same type of vehicle that will carry the Artemis II crew — would be lost.
“I know we’ve been looking at assessments of numbers like Mission Loss and Crew Loss, but I’m not sure we understand what they actually mean,” Honeycutt said, explaining that these numbers often involve estimates.
Honeycutt noted that because Artemis II will mark only the second flight of NASA’s Space Launch System (SLS) rocket, there isn’t much data available to calculate that number for this flight.
“We probably don’t have a 1 in 50 chance that the mission will go exactly as we planned, but we also don’t have a 1 in 2 chance like we did on the first flight,” Honeycutt said of the SLS rocket, which boosts the Orion capsule into orbit. “I think we are being very cautious not to release probabilistic numbers for this mission.”
“I wouldn’t give an exact number,” added Lori Glaze, acting associate administrator for NASA’s Exploration Systems Development Mission Directorate.
“An incredible amount of work was invested in preparing this test flight by thousands of people on our integrated team,” added Glaze.
“We had extremely detailed discussions — very open and transparent,” she said. “We talked a lot about our stance on risks and how we are mitigating those risks.”
Glaze noted that the four Artemis II crew members — NASA’s Reid Wiseman, Victor Glover and Christina Koch, and Canadian Space Agency astronaut Jeremy Hansen — participated in FRR virtually from their base in Houston, Texas.
“Their participation in this review reinforced the importance of having open and honest discussions,” Glaze added.
There are no objections
Glaze said the astronauts watched the broadcast to gain insight into how mission managers evaluated the Orion spacecraft’s heat shield. The heat shield is a crucial component designed to protect the crew during the capsule’s re-entry into the Earth’s atmosphere after returning from the 10-day trip around the Moon.
as to CNN reported Previously, NASA spent more than a year trying to understand why Orion’s heat shield did not perform as expected during the Artemis I test flight in 2022, returning to Earth with dents and cracks in the material. Artemis II is flying with a similar heat shield, but the agency said it plans to mitigate the risks by altering the Orion capsule’s return trajectory — an assessment some critics consider inappropriate.
Glaze said NASA has an internal consensus that the heat shield is safe and that the Artemis II mission is ready to fly.
“I think we all agree we have a good heat shield,” she said. The astronauts “were attentive to make sure everything was really perfect,” including details on how the group will stay in contact with mission controllers on the ground during reentry.
Historically, some flight readiness review meetings have been controversial. During the Space Shuttle era, for example, events could involve tense disagreements between experts.
“A good Flight Review (FRR) for the space shuttle could last two days or more, with long presentations, thought-provoking questions, sometimes heated debates, and finally a resolution: fly or suspend operations and make repairs,” remembered once Wayne Hale, former NASA Space Shuttle Program manager and flight director.
A NASA spokesperson said this week’s FRR lasted all day Wednesday and ended Thursday afternoon, before the 3 p.m. ET press conference.
“We set aside quiet time to give people plenty of opportunity to come to the table and share any dissenting concerns, and there were none,” Honeycutt said.
Technical issues
Still, Artemis II mission managers had many technical issues to discuss.
In preparation for the meeting, the SLS rocket suffered a series of setbacks. Among them, problems with liquid hydrogen — a supercooled propellant notorious for leaking — which was escaping from the rocket at rates above acceptable during an initial fueling test. Hydrogen is highly energetic and easy to ignite, posing an explosion risk if excessive accumulation occurs in an area.
Just as NASA appeared to have resolved the fuel leak problem, the agency was faced with a new problem in late February: Helium wasn’t flowing properly into the top of the rocket. Helium is crucial because it is used to clean propellant lines and help pressurize fuel tanks.
This problem made the launch in March unfeasible and led NASA to remove the rocket from the launch pad for maintenance. In fact, the spacecraft is still in NASA’s vehicle assembly building, which is about 4 miles from the launch pad.
The space agency now plans to return the SLS rocket to its launch site on March 19. The journey is a slow process that takes 10 to 12 hours to complete.
Additionally, the rocket’s initial journey to the launch pad may have been responsible for causing some of the hydrogen leaks, as Amit Kshatriya, associate administrator at NASA, revealed in a statement. press conference held on February 3rd.
It’s not yet clear whether these hydrogen-related issues could resurface once SLS returns to launch position.
The space agency confirmed on Thursday, however, that it was able to resolve the helium flow issue by repairing a blocked seal on a cable connecting the rocket to nearby Earth systems.
NASA said it chose not to conduct another full fuel test — a test in which launch controllers fill the rocket with fuel and perform a full hands-on test in preparation for launch.
The last general test with water, at the end of February, was successful. But it ended shortly before NASA identified the problem with the helium flow.
Glaze stated that one of the reasons for not carrying out another refueling test in water is to preserve the fuel tanks: each time NASA fills them with propellant, “it reduces the useful life of these tanks a little.”
She added: “We don’t want to lose any of the days of our April launch period to a rainy day dress rehearsal.”
