On Oct. 19, the Orion crew and service modules for the Artemis II mission were joined together inside the Neil Armstrong Operations and Checkout Building at NASA’s Kennedy Space Center in Florida.
After successfully completing hardware installations and testing over the past several months, engineers connected the two major components of Orion that will fly NASA astronauts Reid Wiseman, Victor Glover, and Christina Koch, along with CSA (Canadian Space Agency) astronaut Jeremy Hansen on a mission around the Moon and bring them home safely.
Now that the crew and service modules are integrated, the team will power up the combined crew and service module for the first time. After power on tests are complete, Orion will begin altitude chamber testing, which will put the spacecraft through conditions as close as possible to the environment it will experience in the vacuum of deep space.
Technicians at NASA’s Michoud Assembly Facility in New Orleans have installed the first of four RS-25 engines on the core stage of the agency’s SLS (Space Launch System) rocket that will help power NASA’s first crewed Artemis mission to the Moon. During Artemis II, NASA astronauts Reid Wiseman, Victor Glover, Christina Koch, and CSA (Canadian Space Agency) astronaut Jeremy Hansen will launch on SLS and journey around the Moon inside the Orion spacecraft during an approximately 10-day mission in preparation for future lunar missions.
The Sept. 11 engine installation follows the joining of all five major structures that make up the SLS core stage earlier this spring. NASA, lead RS-25 engines contractor Aerojet Rocketdyne, an L3 Harris Technologies company, and Boeing, the core stage lead contractor, will continue integrating the remaining three engines into the stage and installing the propulsion and electrical systems within the structure.
All four RS-25 engines are located at the base of the core stage within the engine section, which protects the engines from the extreme temperatures during launch and has an aerodynamic boat tail fairing to channel airflow. During launch and flight, the four engines will fire nonstop for over eight minutes, consuming propellant from the core stage’s two massive propellant tanks at a rate of 1,500 gallons (5,678 liters) per second.
Each SLS engine has a different serial number. The serial number for the engine installed Sept. 11 in position two on the core stage is E2059. It along with the engine in position one, E2047, previously flew on space shuttle flights. E2047 is the most veteran engine of the entire set flying on Artemis II with 15 shuttle flights, including STS-98, which delivered the Destiny Laboratory Module to the International Space Station in 2001. The engines installed in positions three and four (E2062 and E2063) are new engines that include previously flown hardware.
NASA is working to land the first woman and first person of color on the Moon under Artemis. SLS is part of NASA’s backbone for deep space exploration, along with Orion and the Gateway in orbit around the Moon, and commercial human landing systems. SLS is the only rocket that can send Orion, astronauts, and supplies to the Moon in a single mission.
On Aug. 13, engineers and technicians inside the high bay of the Neil Armstrong Operations and Checkout Building at NASA’s Kennedy Space Center in Florida successfully completed a series of acoustic tests to ensure the Orion spacecraft for NASA’s Artemis II mission can withstand the speed and vibration it will experience during launch and throughout the 10-day mission around the Moon, the first Artemis mission with astronauts.
During the testing, engineers surrounded the crew module with large stacks of speakers, and attached microphones, accelerometers, and other equipment to measure the effects of different acoustic levels. Engineers and technicians will now analyze the data collected during the tests.
Prior to testing, the four Artemis II astronauts visited the high bay and viewed their ride to the Moon. With this test complete, technicians at Kennedy are on track to integrate Orion’s crew and service modules this fall.
The Artemis II crew – NASA astronauts Reid Wiseman, Victor Glover, Christina Hammock Koch, and Canadian Space Agency astronaut Jeremy Hansen – visited Naval Base San Diego on July 19 ahead of the first Artemis II recovery test in the Pacific Ocean, Underway Recovery Test-10. The test will build on the success of Artemis I recovery and ensure NASA and the Department of Defense personnel can safely recover astronauts and their Orion spacecraft after their trip around the Moon on the first crewed Artemis mission.
The crew met with recovery team members from NASA’s Exploration Ground Systems Program and the Department of Defense to learn more about the recovery process for their mission, which includes being extracted from the spacecraft after splashing down in the Pacific Ocean and being lifted via helicopter to the recovery ship where they will undergo routine medical checks before returning to shore.
The visit included a walkdown of the ground equipment and facilities the team uses to practice recovery procedures along with a walkthrough of the recovery ship. The crew will participate in full recovery testing at sea next year.
On June 25, 2023, teams completed installation of the heat shield for the Artemis II Orion spacecraft inside the high bay of the Neil Armstrong Operations and Checkout Building at NASA’s Kennedy Space Center in Florida.
The 16.5-foot-wide heat shield is one of the most important systems on the Orion spacecraft ensuring a safe return of the astronauts on board. As the spacecraft returns to Earth following its mission around the Moon, it will be traveling at speeds of about 25,000 mph and experience outside temperatures of nearly 5,000 degrees Fahrenheit. Inside the spacecraft, however, astronauts will experience a much more comfortable temperature in the mid-70s thanks to Orion’s thermal protection system.
Up next, the spacecraft will be outfitted with some of its external panels ahead of acoustic testing later this summer. These tests will validate the crew module can withstand the vibrations it will experience throughout the Artemis II mission, during launch, flight, and landing.
Once acoustic testing is complete, technicians will attach the crew module to Orion’s service module, marking a major milestone for the Artemis II mission, the first mission with astronauts under Artemis that will test and check out all of Orion’s systems needed for future crewed missions.
The Orion spacecraft is on its last full day in space with splashdown off the Baja Coast near Guadalupe Island targeted for 11:39 a.m. CST (12:39 p.m. EST) on Sunday, Dec. 11.
Engineers conducted the final Artemis I in-space developmental flight test objective to characterize temperature impacts on solar array wings from plumes, or exhaust gases. Once the solar array wing was in the correct test position, flight controllers fired the reaction control system thrusters using opposing thrusters simultaneously to balance the torque and test a variety of firing patterns. Engineers will perform several additional flight test objectives after Orion splashes down in the water and before powering down the spacecraft.
The fifth return trajectory correction burn occurred at 2:32 p.m. CST, Saturday, Dec. 10. During the burn the auxiliary engines fired for 8 seconds, accelerating the spacecraft by 3.4 mph (5 feet per second) to ensure Orion is on course for splashdown. The sixth and final trajectory correction burn will take place about five hours before Orion enters Earth’s atmosphere.
On Orion’s return to Earth, NASA’s Tracking and Data Relay Satellite (TDRS) will facilitate communications for the final return trajectory correction burn, spacecraft separation, re-entry through the Earth’s atmosphere and splashdown. Shortly before the service module separates from the crew module, communication will be switched from NASA’s Deep Space Network to its Near Space Network for the remainder of the mission. Located in geosynchronous orbit about 22,000 miles above Earth, TDRS are used to relay data from spacecraft at lower altitudes to ground antennas. During re-entry, the intense heat generated as Orion encounters the atmosphere turns the air surrounding the capsule into plasma and briefly disrupts communication with the spacecraft.
Recovery forces have arrived on location off the coast of Baja where they will stand by to greet the spacecraft after its re-entry back into the atmosphere at 25,000 mph. On the ship, personnel are running through preparations and simulations to ensure the interagency landing and recovery team, led by Exploration Ground Systems from Kennedy Space Center in Florida, is ready to support recovery operations. The team consists of personnel and assets from the U.S. Department of Defense, including Navy amphibious specialists and Space Force weather specialists, and engineers and technicians from Kennedy Space Center in Florida, Johnson Space Center in Houston, and Lockheed Martin Space Operations.
Teams will recover Orion and attempt to recover hardware jettisoned during landing, including the forward bay cover and three main parachutes. A four-person team of engineers from Johnson will be aboard the U.S. Navy recovery ship using “Sasquatch” software to identify the footprint of hardware released from the capsule. The primary objective for the Sasquatch team is to help the ship get as close as possible to Orion for a quick recovery. A secondary objective is to recover as many additional elements as possible for analysis later.
Just after 2 p.m. CST Dec. 10, Orion was 113,453 miles from Earth and 239,432 miles from the Moon, cruising at 3,375 miles per hour.
Live coverage of Orion’s reentry and splashdown will begin at 11 a.m. EST on NASA TV, the agency’s website, and the NASA app. A post-splashdown briefing is scheduled for about 3:30 p.m.
NASA’s Orion spacecraft is on course for its return to Earth on Sunday, Dec. 11. The spacecraft made its second and final close approach to the Moon at 10:43 a.m. CST Monday, Dec. 5, just before its return powered flyby burn, passing 80.6 miles above the lunar surface.
The burn, which used the spacecraft’s main engine on the European-built service module, lasted 3 minutes, 27 seconds, and changed the velocity of the spacecraft by about 655 mph (961 feet per second). It was the final major engine maneuver of the flight test.
“Orion is heading home! Today the team achieved another momentous accomplishment, flying Orion just 80 miles from the surface of the Moon. The lunar flyby enabled the spacecraft to harness the Moon’s gravity and slingshot it back toward Earth for splashdown,” said Administrator Bill Nelson. “When Orion re-enters Earth’s atmosphere in just a few days, it will come back hotter and faster than ever before – the ultimate test before we put astronauts on board. Next up, re-entry!”
Several hours before the lunar flyby, the spacecraft performed a trajectory correction burn at 4:43 a.m. CST using the reaction control system thrusters on the service module. The burn lasted 20.1 seconds and changed the velocity of the spacecraft by 1.39 mph (2.04 feet per second).
The mission management team convened and polled “go” to deploy recovery assets off the coast of California ahead of Orion’s splashdown on Dec. 11. As soon as Orion splashes down, a team of divers, engineers, and technicians will depart the ship on small boats and arrive at the capsule. Once there, they will secure it and prepare to tow it into the back of the ship, known as the well deck. The divers will attach a cable to pull the spacecraft into the ship, called the winch line, and up to four additional tending lines to attach points on the spacecraft. The winch will pull Orion into a specially designed cradle inside the ship’s well deck and the other lines will control the motion of the spacecraft. Once Orion is positioned above the cradle assembly, the well deck will be drained and Orion will be secured on the cradle.
“Last week, we completed our final rehearsal with the USS Portland, which will be our recovery ship for Artemis I,” said Melissa Jones, landing and recovery director, NASA’s Kennedy Space Center. “We had a great three days working with them to refine our procedures and integrate our teams so we can meet the objectives of recovering the Orion spacecraft.”
Orion has used approximately 8,050 pounds of propellant during Artemis I, which is 180 pounds less than expected prelaunch. There are 2,075 pounds of margin available over what was planned for the mission, a 165-pound increase.
As of 5:29 p.m. CST on Dec. 5, Orion was traveling 244,629 miles from Earth and 16,581 miles from the Moon, cruising at 668 mph.
NASA Television and the agency’s website will resume live coverage of Orion’s journey at 9 a.m. Tuesday.
As Orion leaves the lunar sphere of influence for the final time, watch NASA astronaut Thomas Marshburn read the children’s book Goodnight Moon from space during his expedition aboard the International Space Station as part of acollaboration with Crayola Education to bring stories and the unique teachings of space to life with art and creativity.
Images are sent down to Earth, and uploaded to NASA’s Johnson Space Center Flickr account and Image and Video Library. When bandwidth allows, views of the mission will be available in real-time via video stream.
Orion performed the second return trajectory correction burn on Sunday, Dec. 4, at 10:43 a.m. CST, using the auxiliary thrusters and increasing the spacecraft’s velocity by 1.16 mph (1.71 feet per second).
Shortly after acquiring signal with the Deep Space Network’s Canberra ground station at 12:41 a.m. CST, Orion experienced an issue with a power conditioning distribution unit (PCDU), in which four of the latching current limiters responsible for downstream power were switched off. These lower-level switches connect to the propulsion and heater subsystems. Teams confirmed the system was healthy and successfully repowered the downstream components. There was no interruption of power to any critical systems, and there were no adverse effects to Orion’s navigation or communication systems.
Teams are examining whether a potential contributor to this issue is related to a power configuration test implemented by the flight teams to investigate previous instances in which one of eight units opened without a command. The umbilical was successfully commanded closed each time and there was no loss of power flowing to avionics on the spacecraft.
The spacecraft obtained additional data using its optical navigation system, which is a sensitive camera to take images of the Moon and Earth to help orient the spacecraft by looking at the size and position of the celestial bodies in the images. Engineers also continue to work plans to accomplish several additional test objectives during Orion’s journey back to Earth. A host of test objectives provide information to engineers about how Orion operates in space, allowing them opportunities to validate performance models and learn as much as possible about the spacecraft.
In preparation for Orion’s return to Earth, the team from NASA’s Exploration Ground Systems Program and the U.S. Navy, who will recover Orion from the Pacific Ocean, completed its final training day at sea, using a mock capsule in the water for divers and small boats to practice open water recovery procedures.
On Monday, Dec. 5, Orion will make its closest approach to the Moon, flying 79.2 miles above the lunar surface. It will perform the return powered flyby burn at 10:43 a.m. CST, which will last about 3 minutes and 27 seconds, changing the velocity of the spacecraft by approximately 655 mph (961 feet per second). The return powered flyby is the last large maneuver of the mission, with only smaller trajectory corrections to target Earth remaining.
Live coverage of the close lunar flyby and burn will begin at 8 a.m. CST on NASA TV, the agency’s website, and the NASA app. During the coverage, lighting will be different than it was during Orion’s initial close lunar flyby on Nov. 21. The spacecraft will lose communications with Earth for approximately 31 minutes beginning at 10:40 a.m. CST, as it flies behind the far side of the Moon.
At 4 p.m. CST on Dec. 5, NASA leaders will discuss the results of the return powered flyby burn and the deployment of recovery assets to sea ahead of Orion’s splashdown on Dec. 11. Live coverage will be available on all NASA channels.
Just after 4:30 p.m. CST on Dec. 4, Orion was traveling 222,213 miles from Earth and 23,873 miles from the Moon, cruising at 3,076 mph.
Orion re-entered the lunar sphere of influence at 4:45 p.m. CST Saturday, Dec. 3, making the Moon the main gravitational force acting on the spacecraft. Entry into the lunar sphere of entry occurred when the spacecraft was about 39,993 miles from the lunar surface. It will exit the lunar sphere of influence for a final time on Tuesday, Dec. 6, one day after the return powered flyby about 79 miles above the lunar surface.
On Flight Day 18, engineers also performed a development flight test objective that changed the minimum jet firing time for the reaction control thrusters over a period of 24 hours. This test objective is designed to exercise the reaction control system jets in a pre-planned sequence to model jet thruster firings that will be incorporated into the crewed Artemis II mission.
The test used the reaction control system (RCS) thrusters, built by ArianeGroup, on the European Service Module. All firings of RCS thrusters during the flight test to date have used those on the service module. Another set of 12 RCS thrusters, built by Aerojet Rocketdyne, are located on the crew module.
While the crew module thrusters will be tested a few days before Orion’s splashdown on Earth, their primary role takes place in the final hour before splashdown in the Pacific Ocean. After the crew module and service module separate the crew module’s RCS thrusters will be used to ensure the spacecraft is properly oriented for re-entry, with its heat shield pointed forward, and stable during descent under parachutes.
Orion will be out of communication with NASA’s Deep Space Network for about 4.5 hours from 7:40 p.m. to 12:00 a.m. while network teams reconfigure ground stations. The flight control team has adjusted the activity timeline, and there is no impact to the mission’s trajectory. Automated commands will guide the spacecraft during this period, and Orion will reacquire signal as it passes within range of the Canberra ground station.
Just after 4:30 p.m. on Dec. 3, Orion was traveling 221,630 miles from Earth and 40,086 miles from the Moon, cruising at 2,777 miles per hour.
After departing distant retrograde orbit the afternoon of Thursday, Dec. 1, Orion completed a planned trajectory correction burn to fine-tune its course toward the Moon. The five-second burn occurred at 9:54 p.m. CST Thursday, and changed the spacecraft’s velocity by about 0.3 mph or less than half a foot per second.
Dec. 2, teams collected additional images with Orion’s optical navigation camera and downlinked a wide variety of data files to the ground, including data from the Hybrid Electronic Radiation Assessor, or HERA. The radiation detector measures charged particles that pass through its sensors. Measurements from HERA and several other radiation-related sensors and experiments aboard Artemis I will help NASA better understand the space radiation environment future crews will experience and develop effective protections. On crewed missions, HERA will be part of the spacecraft’s caution and warning system and will sound a warning in the case of a solar energetic particle event, notifying the crew to take shelter. NASA is also testing a similar HERA unit aboard the International Space Station.
Orion carries other experiments to gather data on radiation, including several radiation area monitors about the size of a matchbox that record the total radiation dose during the mission, dosimeters provided by ESA (European Space Agency) mounted inside the cabin to collect radiation data with time stamps to allow scientists to assess dose rates during various mission phases, and three “purposeful passengers” collecting additional information on what crews will experience during future missions. Four space biology investigations, collectively called Biology Experiement-1, are examining the impact of deep space radiation on seeds, fungi, yeast, and algae.
Orion will reenter the lunar sphere of influence on Saturday, Dec. 3, making the Moon the main gravitational force acting on the spacecraft. It will exit the lunar sphere of influence for a final time on Tuesday, Dec. 6, one day after its return powered flyby about 79 miles above the lunar surface.
A total of about 7,940 pounds of propellant has been used, which is about 150 pounds less that the amount expected before launch. Approximately 2,040 pounds of margin is available beyond what flight controllers plan to use for the remainder of the mission, which is nearly 130 pounds more than expected amounts before launch. About 97 gigabytes of data have been sent to the ground by the spacecraft.
Just after 1 p.m. CST on Dec. 2, Orion was traveling 229,812 miles from Earth and 50,516 miles from the Moon, cruising at 2,512 miles per hour.