The Orion spacecraft for Artemis 1 was stacked on October 20, 2021, marking the first time a super-heavy-lift vehicle has been stacked inside NASA's Vehicle Assembly Building (VAB) since the final Saturn V in 1973. On August 17, 2022, the fully stacked vehicle was rolled out for launch after a series of delays caused by difficulties in pre-flight testing. The first two launch attempts were canceled due to a faulty engine temperature reading on August 29, 2022, and a hydrogen leak during fueling on September 3, 2022.
Once in orbit, the ICPS fired its engine to perform a trans-lunar injection (TLI) burn, which placed the Orion spacecraft and ten CubeSats on a trajectory to the Moon. Orion then separated from the ICPS and continued its coast into lunar space. Following Orion separation, the ICPS Stage Adapter deployed ten CubeSats for conducting scientific research and performing technology demonstrations.
The Orion spacecraft is expected to spend approximately three weeks in space, including six days in a distant retrograde orbit (DRO) around the Moon. It is expected to come within approximately 130 km (80 mi) of the lunar surface (closest approach) and to have a maximum distance from Earth of 480,494 km (298,565 mi).
In January 2013 it was announced that the Orion spacecraft's service module was to be built by the European Space Agency and named the European Service Module. In mid-November 2014 construction of the SLS core stage began at NASA's Michoud Assembly Facility (MAF). In January 2015 NASA and Lockheed Martin announced that the primary structure in the Orion spacecraft used on Artemis 1 would be up to 25% lighter compared to the previous one (EFT-1). This would be achieved by reducing the number of cone panels from six (EFT-1) to three (EM-1), reducing the total number of welds from 19 to 7 and saving the additional mass of the weld material. Other savings would be due to revising its various components and wiring. For Artemis 1, the Orion spacecraft was to be outfitted with a complete life support system and crew seats but would be left uncrewed.
Block 1 variant of SLS rocket
In February 2017, NASA began investigating the feasibility of a crewed launch as the first SLS flight. It would have had a crew of two astronauts and the flight time would have been shorter than the uncrewed version. However, after a months-long feasibility study, NASA rejected the proposal, citing cost as the primary issue, and continued with the plan to fly the first SLS mission uncrewed.
In March 2019, then-NASA administrator Jim Bridenstine proposed moving the Orion spacecraft from SLS to commercial rockets, either the Falcon Heavy or Delta IV Heavy, to comply with the schedule. The mission would require two launches: one to place the Orion spacecraft into orbit around the Earth, and a second carrying an upper stage. The two would then dock while in Earth orbit, and the upper stage would ignite to send Orion to the Moon. The idea was eventually scrapped. One challenge with this option would be carrying out that docking, as Orion is not planned to carry a docking mechanism until Artemis 3. The concept was shelved in mid-2019, due to another study's conclusion that it would further delay the mission.
First static-fire attempt of the core stage performed on January 16, 2021
The core stage for Artemis 1, built at Michoud Assembly Facility by Boeing, had all four engines attached in November 2019 and was declared finished one month later. The core stage left the facility to undergo the Green Run test series at Stennis Space Center, consisting of eight tests of increasing complexity:
The first test was performed in January 2020, and subsequent Green Run tests proceeded without issue. On January 16, 2021, a year later, the eighth and final test was performed, but the engines shut down after running for one minute. This was caused by pressure in the hydraulic system used for the engines' thrust vector control system dropping below the limits set for the test. However, the limits were conservative – if such an anomaly occurred in launch, the rocket would still fly normally. The static fire test was performed again on March 18, 2021, this time achieving a full-duration eight-minute burn. The core subsequently departed the Stennis Space Center on April 24, 2021, on route to the Kennedy Space Center.
The Interim Cryogenic Propulsion Stage was the first part of the SLS to be delivered to the Kennedy Space Center in July 2017. Three years later, all of the SLS's solid rocket booster segments were shipped by train to the Kennedy Space Center on June 12, 2020, and the SLS launch vehicle stage adapter (LVSA) was delivered by barge one month later on July 29, 2020. The assembly of the SLS took place at the Vehicle Assembly Building's High Bay 3, beginning with the placement of the two bottom solid rocket booster segments on November 23, 2020. Assembly of the boosters was temporarily paused due to the core stage Green Run test delays before being resumed on January 7, 2021, and the boosters' stacking was completed by March 2, 2021.
The SLS core stage for the mission, CS-1, arrived at the launch site on the Pegasus barge on April 27, 2021, after the successful conclusion of Green Run tests. It was moved to the VAB low bay for refurbishment and stacking preparations on April 29, 2021. The stage was then stacked with its boosters on June 12, 2021. The stage adapter was stacked on the Core Stage on June 22, 2021. The ICPS upper stage was stacked on July 6, 2021. Following the completion of umbilical retract testing and integrated modal testing, the Orion stage adapter with ten secondary payloads was stacked atop the upper stage on October 8, 2021.
The Artemis 1 Orion spacecraft began fueling and pre-launch servicing in the Multi-Payload Processing Facility on January 16, 2021, following a handover to NASA Exploration Ground Systems (EGS). On October 20, 2021, the Orion spacecraft, encapsulated under the launch abort system and aerodynamic cover, was rolled over to the VAB and stacked atop the SLS rocket, finishing the stacking of the Artemis 1 vehicle in High Bay 3. During a period of extensive integrated testing and checkouts, one of the four RS-25 engine controllers failed, requiring a replacement and delaying the first rollout of the rocket.
First rollout of SLS in March 2022; it was then rolled back in for repairs
On March 17, 2022, Artemis 1 rolled out of High Bay 3 from the Vehicle Assembly Building for the first time to perform a pre-launch wet dress rehearsal (WDR). The initial WDR attempt, on April 3, was scrubbed due to a mobile launcher pressurization problem. A second attempt to complete the test was scrubbed on April 4, after problems with supplying gaseous nitrogen to the launch complex, liquid oxygen temperatures, and a vent valve stuck in a closed position.
During preparations for a third attempt, a heliumcheck valve on the ICPS upper stage was kept in a semi-open position by a small piece of rubber originating from one of the mobile launcher's umbilical arms, forcing test conductors to delay fueling the stage until the valve could be replaced in the VAB. The third attempt to finish the test did not include fueling the upper stage. The rocket's liquid oxygen tank started loading successfully. However, during the loading of liquid hydrogen on the core stage, a leak was discovered on the tail service mast umbilical plate, located on the mobile launcher at the base of the rocket, forcing another early end to the test.
NASA elected to roll the vehicle back to the VAB to repair the hydrogen leak and the ICPS helium check valve while upgrading the nitrogen supply at LC-39B after prolonged outages on the three previous wet dress rehearsals. Artemis 1 was rolled back to the VAB on April 26. After the repairs and upgrades were complete the Artemis 1 vehicle rolled out to LC-39B for a second time on June 6 to complete the test.
During the fourth wet dress rehearsal attempt on June 20, the rocket was fully loaded with propellant on both stages. Still, due to a hydrogen leak on the quick-disconnect connection of the tail service mast umbilical, the countdown could not reach the planned T-9.3 seconds mark and was stopped automatically at T-29 seconds. NASA mission managers soon determined they had completed almost all planned test objectives and declared the WDR campaign complete.
On July 2, the Artemis 1 stack was rolled back to the VAB for final launch preparations and to fix the hydrogen leak on the quick disconnect ahead of a launch targeted in two launch windows: August 29 and September 5. The SLS passed flight readiness review on August 23, checking out five days before the first launch opportunity.
Initial launch attempts
Fueling was scheduled to commence just after midnight on August 29, 2022, but was delayed an hour due to offshore storms, only beginning at 1:13 am EDT. Before the planned launch at 8:33 am, Engine 3 of the rocket's four engines was observed to be above the maximum allowable temperature limit for launch. Other technical difficulties involved an eleven-minute communications delay between the spacecraft and ground control, a fuel leak, and a crack on the insulating foam of the connection joints between the liquid hydrogen and liquid oxygen tanks. NASA scrubbed the launch after an unplanned hold and the two-hour launch window expired. An investigation revealed that a sensor not used to determine launch readiness was faulty, and displayed an erroneously high temperature for Engine 3.
Following the first attempt, a second launch attempt was scheduled for the afternoon of September 3. The launch window would have opened at 2:17 pm EDT (18:17 UTC), and lasted for two hours. The launch was scrubbed at 11:17 am EDT due to a fuel supply line leak in a service arm connecting to the engine section. The cause of the leak was uncertain. Mission operators investigated whether an overpressurization of the liquid hydrogen line of the quick-disconnect interface during the launch attempt may have damaged a seal, allowing hydrogen to escape.
Launch operators decided on the date for the next launch attempt; the earliest possible opportunity was September 19 until mission managers declared that September 27, and then September 30, would be the absolute earliest date, NASA having successfully repaired the leak. A launch in September would have required that the Eastern Range of the United States Space Force agree to an extension on certification of the rocket's flight termination system, which destroys the rocket should it move off-course and towards a populated area; this was carried out on September 22. However, unfavorable forecasts of the trajectory of then-Tropical Storm Ian led launch managers to call off the September 27 launch attempt and begin preparations for the stack's rollback to the VAB. On the morning of September 26, the decision was made to roll back later that evening.
On November 12, following another delay due to Hurricane Nicole, NASA launch managers decided to request launch opportunities for November 16 and 19. They initially requested an opportunity for the 14th but were prevented by then-Tropical Storm Nicole. As the storm approached, NASA decided to leave the rocket at the launch pad, citing a low probability that wind speeds would exceed the rocket's design limits. Wind speeds were expected to reach 29 mph (47 km/h), with gusts up to 46 mph (74 km/h). Nicole made landfall as a category one hurricane on November 9, with sustained wind speeds at Kennedy Space Center reaching 85 mph (137 km/h), and gusts up to 100 mph (160 km/h), exceeding the rocket's design specifications. After the storm cleared, NASA inspected the rocket for physical damage and conducted electronic health checks. On November 15, the mission management team gave a "go" to begin fully preparing for launch, and the main tanking procedures began at 3:30 pm EST (20:30 UTC).
Launch of Artemis 1
At 6:47:44 UTC (1:47:44 am EST) on November 16, 2022, Artemis 1 successfully launched from Launch Complex 39B at the Kennedy Space Center. It was the first time in nearly 50 years that NASA has launched a rocket intended to travel to the moon, the last time being Apollo 17. This launch also marks the first time since Ares I-X that a rocket has launched from Launch Complex 39B. The Orion spacecraft and ICPS were both placed into a nominal orbit after separating from the Space Launch System, achieving orbit approximately 8 minutes after launch.
The Moon, as seen from Orion, while the spacecraft performed a close flyby of the satellite
Eighty-nine minutes after liftoff, the ICPS fired for approximately eighteen minutes for a trans-lunar injection (TLI) burn. After that, Orion separated from the expended stage and fired its auxiliary thrusters to move safely away as it started its journey to the Moon. The ICPS then deployed 10 CubeSats as secondary payloads from the Orion Stage Adapter. A final burn was completed at three and a half hours after launch to dispose itself into a heliocentric orbit.
On November 20, 2022, at 19:09 UTC, the Orion spacecraft entered the lunar sphere of influence, thus the Moon's gravitational force became stronger than Earth's relative to the spacecraft.
The Moon as seen from Orion on the sixth day of the mission
On November 21, 2022, Orion lost communication with NASA as it passed behind the Moon from 12:25 through 12:59 UTC. There, during an automatically controlled maneuver, the first of a pair of trajectory-altering burns, called "outbound powered flyby burn(s)", to transition Orion to a distant retrograde orbit began at 12:44 UTC. The orbital maneuvering system engine fired for two minutes and thirty seconds. While still autonomous, Orion made its closest lunar approach of approximately 130 km (81 mi) above the surface at 12:57 UTC. The spacecraft performed the second and final outbound powered flyby burn on November 25, firing the orbital maneuvering system for one minute and twenty-eight seconds, propelling Orion to 363 ft/s (398 km/h). On November 26, at 13:42 UTC, Orion broke the record for the farthest distance from Earth traveled by an Earth-returning human-rated spacecraft, at about 270,000 mi (430,000 km). The record was formerly held by the Apollo 13 mission.
On November 30, 2022, the Orion spacecraft performed a maintenance burn to maintain its trajectory and decrease its velocity for a planned burn on December 1, at 21:53 UTC, to depart its distant retrograde orbit around the Moon, beginning its journey back to Earth.
The Orion spacecraft is carrying three astronaut-like mannequins equipped with sensors to provide data on what crew members may experience during a trip to the Moon. The first mannequin, called "Captain Moonikin Campos" (named after Arturo Campos, a NASA engineer during the Apollo program), occupies the commander's seat inside Orion and is equipped with two radiation sensors in his Orion Crew Survival System suit, which astronauts will wear during launch, entry, and other dynamic phases of their missions. The commander's seat also has sensors to record acceleration and vibration data during the mission.
Alongside Moonikin are two phantom torsos: Helga and Zohar, who will take part in the Matroshka AstroRad Radiation Experiment (MARE), in which NASA, together with the German Aerospace Center and the Israel Space Agency, will measure the radiation exposure during the mission. Zohar is shielded with the Astrorad radiation vest and equipped with sensors to determine radiation risks. Helga does not wear a vest. The phantoms will measure the radiation exposure of body location, with both passive and active dosimeters distributed at sensitive and high stem cell-concentration tissues. The test is to provide data on radiation levels during missions to the Moon while testing the effectiveness of the vest. In addition to the three mannequins, Orion carries a plush doll of NASA's Snoopy and a Shaun the Sheep toy representing the ESA's European Service Module contribution to the mission.
Besides these functional payloads, Artemis 1 also carries commemorative stickers, patches, seeds, and flags from contractors and space agencies worldwide. A technology demonstration called Callisto, named after the mythical figure associated with Artemis, developed by Lockheed Martin in collaboration with Amazon and Cisco, is also in flight aboard Orion on Artemis 1. Callisto will use video conferencing software to transmit audio and video from mission control and use the Alexa virtual assistant to respond to the audio messages. In addition, as of August 2022, the public could submit messages to be displayed on Callisto during the Artemis 1 mission.[needs update]
Orion spacecraft's stage adapter with nine out of ten CubeSats installed
Another three CubeSats were originally planned to launch on Artemis 1 but missed the integration deadline, and will have to find alternative flights to the Moon. The stage adapter contains thirteen CubeSat deployers in total.
Lunar Flashlight is a lunar orbiter that would seek exposed water ice and map its concentration at the 1–2 km (0.62–1.24 mi) scale within the permanently shadowed regions of the lunar south pole. Remanifested on Hakuto-R Mission 1 on a Falcon 9.
Sample souvenir boarding pass for those who registered their names to be flown aboard the Artemis 1 mission
The Artemis 1 mission patch was created by NASA designers of the SLS, Orion spacecraft and Exploration Ground Systems teams. The silver border represents the color of the Orion spacecraft; at the center, the SLS and Orion are depicted. Three lightning towers surrounding the rocket symbolize Launch Complex 39B, from which Artemis 1 will launch. The red and blue mission trajectories encompassing the white full Moon represent Americans and people in the European Space Agency who work on Artemis 1.
The Artemis 1 flight is frequently marketed as the beginning of Artemis's "Moon to Mars" program, though there is no concrete plan for a crewed mission to Mars within NASA as of 2022. To raise public awareness, NASA made a website for the public to get a digital boarding pass of the mission. The names submitted were written to a flash drive stored inside the Orion spacecraft. Also aboard the capsule is a digital copy of the 14,000 entries for the Moon Pod Essay Contest hosted by Future Engineers for NASA.
^Artemis: brand book (Report). Washington, D.C.: NASA. 2019. NP-2019-07-2735-HQ. MISSION NAMING CONVENTION: While Apollo mission patches used numbers and roman numerals throughout the program, Artemis mission names will use a roman numeral convention. This article incorporates text from this source, which is in the public domain.
^Berger, Thomas (October 11–12, 2017). Exploration Missions and Radiation(PDF). International Symposium for Personal and Commercial Spaceflight. Las Cruces, New Mexico: ISPCS. Archived from the original(PDF) on June 22, 2018. Retrieved June 22, 2018.
^"Lunar Flashlight". Solar System Exploration Research Virtual Institute. NASA. 2015. Archived from the original on September 13, 2016. Retrieved May 23, 2015. This article incorporates text from this source, which is in the public domain.
Launches are separated by dots ( • ), payloads by commas ( , ), multiple names for the same satellite by slashes ( / ). Crewed flights are underlined. Launch failures are marked with the † sign. Payloads deployed from other spacecraft are (enclosed in brackets).