The Artemis I mission management team met this afternoon to review the status of the operations and have given a “go” for a Sept. 3 launch attempt of the Space Launch System rocket and Orion spacecraft. Since the previous launch attempt on Monday, Aug. 29, teams have updated procedures, practiced operations and refined timelines.
Over the last day, teams worked to fix a leak on the tail service mast umbilical by replacing a flex-hose and a loose pressure sensor line, as the likely the source of the leak. Teams also retorqued, or tightened, the bolts surrounding that enclosure to ensure a tight seal when introducing the super-cooled propellants through those lines. While there was no leak detected at ambient temperatures, teams will continue to monitor during tanking operations.
Teams will adjust the procedures to chill down the engines, also called the kick start bleed test, about 30 to 45 minutes earlier in the countdown during the liquid hydrogen fast fill phase for the core stage. This will to allow for additional time to cool the engines to appropriate temperatures for launch.
Meteorologists with the U.S. Space Force Space Launch Delta 45 predict 60% favorable weather conditions, improving throughout the window for Saturday.
Jeremy Parsons, Exploration Ground Systems, deputy program manager, NASA Kennedy
Melody Lovin, weather officer, Space Launch Delta 45
On Saturday, live coverage of tanking operations with commentary on NASA TV will begin at 5:45 a.m. EDT. Full launch coverage in English will begin at 12:15 p.m. and NASA en espanol broadcast coverage will begin at 1 p.m. EDT. Click here for the latest information on launch briefings and events.
Artemis Launch Director Charlie Blackwell-Thompson has given the “go” to officially begin loading propellants into the Space Launch System rocket. The launch weather officer now reports there are no indication of lightning within five nautical miles of Launch Pad 39B. Tanking begins with chilldown of the core stage liquid oxygen transfer line.
The Artemis I Mission Management Team has given the “go” to proceed toward tanking operations.
Weather conditions remain 80% favorable at the beginning of the two-hour launch window which opens at 8:33 a.m. EDT Aug. 29, with chances for rain showers increasing toward the later part of the window.
Artemis I launch director Charlie Blackwell-Thompson is scheduled to give the “go” to officially begin propellant loading operations just before midnight.
During tanking operations, teams will fuel the Space Launch System (SLS) rocket with liquid oxygen (LOX) and liquid hydrogen (LH2), beginning with the rocket’s core stage and then the interim cryogenic propulsion stage.
Tanking begins with chilling down the LOX lines for the core stage. The process for the chill down, or cooling, uses the propellant lines to load the rocket’s core stage LOX in preparation for tanking. The LOX tank holds 196,000 gallons of liquid oxygen, cooled to minus 297 degrees Fahrenheit. In sequential fashion, LOX and LH2 will flow into the rocket’s core stage tank and be topped off and replenished as some of the cryogenic propellant boils off.
The process involves slowly filling the core stage with propellant to thermally condition the tank until temperature and pressure are stable before beginning fast fill operations, which is when the tank is filled at a quicker pump speed. As the super cold liquid oxygen fills the core stage tank, some venting may be visible. The team also will conduct leak checks to ensure propellant loading is proceeding as expected.
At midnight, NASA TV coverage begins with commentary of tanking operations to load propellant into the SLS rocket. Full coverage begins at 6:30 a.m. in English and at 7:30, coverage in Spanish begins.
Below are the countdown milestones as planned for tanking:
Core Stage LO2 transfer line chilldown (L-8H15M – L-8H)
Core stage LO2 main propulsion system (MPS) chilldown (L-8H – L-7H20M)
Core stage LO2 slow fill (L-7H20M – L-7H5M)
Core Stage LO2 fast fill (L-7H5M – L-4H15M)
Core Stage LH2 chilldown (L-7H15M – L-7H5M)
Core Stage LH2 slow fill start (L-7H5M – L-6H15M)
Core Stage LH2 fast fill (L-6H15M – L-5H5M)
Core Stage LH2 topping (L-5H5M – L-5H)
L-5 hours and counting
Core Stage LH2 replenish (L-5H – Launch)
ICPS LH2 ground support equipment (GSE) and tank chilldown (L-4H45M – L-4H30M)
ICPS LH2 fast fill start (L-4H30M – L-3H30M)
Orion communications system activated (RF to Mission Control) (L-4H20M – L-3H45M)
Core stage LO2 topping (L-4H15M– L-3H55M)
Core Stage LO2 replenish (L-3H55M – Launch)
ICPS L02 MPS chilldown (L-3H55M– L-3H45M)
ICPS L02 fast fill (L-3H45M– L-2H55M)
ICPS LH2 validation and leak test (L-3H30M – L-3H15M)
ICPS LH2 tank topping start (L-3H15M – L-2H55M)
L-3 hours and counting
ICPS/Space Launch System (SLS) telemetry data verified with Mission Control and SLS Engineering Support Center (L-2H55M – L-2H45M)
ICPS LO2 validation and leak test (L-2H55M – L-2H30M)
The Flight Readiness Review for NASA’s Artemis I mission has concluded, and teams are proceeding toward a two-hour launch window that opens at 8:33 a.m. EDT Monday, August 29, from Kennedy Space Center’s Launch Pad 39B in Florida. NASA will hold a media conference at approximately 8 p.m. to discuss the outcome of the review. Listen live on the agency’s website.
Participants in the teleconference are:
Janet Petro, director, Kennedy Space Center
Bob Cabana, associate administrator, NASA Headquarters
Jim Free, associate administrator for Exploration Systems Development Mission Directorate, NASA Headquarters
Mike Sarafin, Artemis mission manager, NASA Headquarters
Charlie Blackwell-Thompson, Artemis launch director, Exploration Ground Systems Program, Kennedy
Howard Hu, Orion Program manager, Johnson Space Center in Houston
Chris Cianciola, Space Launch System Program deputy manager, NASA’s Marshall Space Flight Center
More details about the mission and Artemis can be found in the press kit, or by following the Artemis blog.
Around 7:30 a.m. EDT the Space Launch System rocket and Orion spacecraft for the Artemis I mission arrived atop Launch Complex 39B at NASA’s Kennedy Space Center in Florida after a nearly 10-hour journey from the Vehicle Assembly Building.
In the coming days, engineers and technicians will configure systems at the pad for launch, which is currently targeted for no earlier than Aug. 29 at 8:33 a.m. (two hour launch window). Teams have worked to refine operations and procedures and have incorporated lessons learned from the wet dress rehearsal test campaign and have updated the launch timeline accordingly.
The Space Launch System rocket and Orion spacecraft for the Artemis I mission are rolling to Launch Complex 39B at the Kennedy Space Center in Florida ahead of launch, currently targeted for Aug. 29. At about 10 p.m. EDT the crawler-transporter began the approximately 4-mile, journey from the Vehicle Assembly Building (VAB) to Launch Pad 39B.
Once outside the VAB high-bay doors, the Moon rocket will make a planned pause allowing the team to reposition the Crew Access Arm before continuing to the launch pad. The journey is expected to take between eight and 12 hours. NASA will provide an update once the rocket has arrived at the launch pad.
Engineers are conducting the last integrated test before the Space Launch System (SLS) rocket and Orion spacecraft roll out to Launch Pad 39B next week for the launch of the Artemis I flight test. This week, teams began the second part of the flight termination system (FTS) test. The first part of the test was conducted earlier this year prior to the wet dress rehearsal.
For safety purposes, all rockets are required to have a system that the Space Launch Delta 45 can use to terminate the flight if necessary. Following completion of the FTS testing, the Eastern Range requires SLS to launch within a certain timeframe. In order to meet the Aug. 29 launch attempt and backup attempts on Sept. 2 and 5, NASA has received an extension from the Space Launch Delta 45 on the validation of the FTS from 20 to 25 days before the system would need to be retested. The waiver will be valid throughout the Artemis I launch attempts.
Once the flight termination system testing is complete, teams will complete final closeouts on SLS and Orion before it rolls out of the Vehicle Assembly Building, including closing out the core stage and solid rocket boosters and retracting the remaining access platforms. The Orion crew module and launch abort system hatches were closed earlier this week, and Orion is in the final preparations for roll.
The Matroshka AstroRad Radiation Experiment torsos, Helga and Zohar, outfitted with sensors to measure radiation levels future crew will be exposed to, have joined Commander Campos and are now installed inside the Orion spacecraft. The final payloads, including the agency’s Biology Experiment-1, will be installed once the rocket and spacecraft are at the pad for launch.
The agency is targeting Thursday, Aug. 18 to roll SLS and the Orion spacecraft to the spaceport’s Launch Pad 39B and will provide a live stream beginning at 6 p.m. EDT Wednesday, Aug. 17 on the NASA Kennedy You Tube channel.
Teams have rescheduled the return of the Space Launch System rocket and Orion spacecraft to the Vehicle Assembly Building (VAB) at NASA’s Kennedy Space Center to Friday, July 1 due a concern with the condition of the crawlerway that leads from Launch Pad 39B to the VAB. First motion is now planned for 6 p.m. EDT.
This afternoon, teams conducted a series of conditioning efforts driving the massive transporter up and down the slope leading to the launch pad. The inclined pathway must be precisely level with an even distribution of the rocks that make up the crawlerway in order to support the load of the mobile launcher and rocket that it will carry.
Teams will continue grating, or sifting, the crawlerway overnight and the rocket and spacecraft remain in a safe configuration.
NASA will roll the Space Launch System rocket and Orion spacecraft for the Artemis I mission from launch pad 39B to the Vehicle Assembly Building (VAB) at the agency’s Kennedy Space Center in Florida beginning Thursday, June 30.
First motion for the rocket and spacecraft atop the mobile launcher is expected to occur at 8 p.m. EDT today. The 4-mile trek atop the crawler transporter from the launch pad to the VAB will take approximately 8-12 hours. The journey previously was expected to begin just after midnight on July 1 but was moved up by several hours due to forecasted weather in the area. Teams will continue monitoring weather in the area and the start of the roll is subject to change.
Teams completed the wet dress rehearsal test campaign for Artemis I on June 20 and have configured the rocket and spacecraft for return to the VAB. Once there, teams will replace a seal on the quick disconnect of the tail service mast umbilical to address a liquid hydrogen leak detected during the rehearsal along with final servicing and checkouts. NASA plans to return the mega Moon rocket to the pad for launch in late August and will set a specific target launch date after replacing hardware associated with the leak.
Over the weekend, teams successfully conducted a test of the thrust vector control system on each of the twin solid rocket boosters of the Space Launch System for Artemis I while the rocket remains at Launch Pad 39B. The test was a follow-on to the wet dress rehearsal test campaign, which was completed last week.
During the test, engineers activated the booster hydraulic power units (HPU), which are hydrazine-powered turbines attached to hydraulic pumps that provide pressure to move the hydraulic actuators that gimbal the booster nozzles. The test verified the normal startup, operations, and shutdown of a fully integrated thrust vector control system, which controls the movement of the nozzles on each of the boosters during ascent. It also verified the rocket’s avionics system using both flight and ground software for the first time. The boosters were not ignited during the test.
The test was part of the objectives that were not completed during the wet dress rehearsal demonstration, as the rehearsal test ended at T-29 seconds during the terminal countdown. During launch, the automated launch sequencer gives the command to activate the HPUs at T-28 seconds.
Teams will drain the hydrazine from the boosters and are in the process of configuring the rocket and Orion spacecraft for their return to the Vehicle Assembly Building (VAB) at the end of the week. Once there, teams will replace a seal on the quick disconnect of the tail service mast umbilical to address a liquid hydrogen leak detected during the rehearsal. NASA plans to return the mega Moon rocket to the pad for launch in late August and will set a specific target launch date after replacing hardware associated with the leak.