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franky1

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Artemis I — I Flight Day 14: Deep Space Testing Continues


(Nov. 24, 2022) On flight day 9, the inside of Orion shows the display of the Callisto payload. Callisto is Lockheed Martin’s technology demonstration in collaboration with Amazon and Cisco, testing voice-activated and video technology that may assist future astronauts on deep space missions.


Engineers continued with the jet firing development flight test objective that began on flight day 12. Today, teams demonstrated the “low” portion of the reaction control thruster firing time range. This test objective is designed to exercise the reaction control system jets in a different configuration to model how thruster jets will be used during the Artemis II mission, furthering our understanding of spacecraft operations before we have crew onboard.


As part of planned testing throughout the mission, the guidance, navigation, and control officer, also known as GNC, performed the sixth of eight planned tests of the star trackers that support Orion’s navigation system. Star trackers are a navigation tool that measure the positions of stars to help the spacecraft determine its orientation. The star trackers continue to provide excellent data to develop our required navigation solutions.


Engineers will characterize the alignment between the star trackers that are part of the guidance, navigation and control system and the Orion inertial measurements units, by exposing different areas of the spacecraft to the Sun and activating the star trackers in different thermal states to determine if the temperature differences induce any changes. The inertial measurement units contain three devices, called gyros, used to measure spacecraft body rotation rates, and three accelerometers used to measure spacecraft accelerations.


A new flight test objective was added to flight day 14 to collect additional information on the thermal characterization of Orion. During a majority of the mission Orion is typically in a tail-to-sun attitude, meaning that the solar arrays face toward the sun to generate power. This flight test objective purposefully orients Orion outside of a perfect tail-to-sun attitude by up to 20 degrees in order to evaluate the spacecraft and gather additional data. Currently, when Orion is out of the tail-to-sun attitude for more than three hours, a ten-hour tail-to-sun recovery period is required. This additional flight test objective will help engineers understand the range of Orion’s thermal performance to incorporate into Artemis II and beyond.


Time in distant retrograde orbit allows engineers to test the spacecraft and its systems in a deep-space environment ahead of future missions with crew. Distant retrograde orbit is a highly stable orbit where little fuel is required to stay for an extended period. While visiting a distant retrograde orbit allows engineers to capitalize on an orbit that was comprehensively studied as part of mission planned for earlier agency efforts, future Artemis mission will visit different orbits.


On Artemis II, four astronauts in Orion will travel around the Moon and fly several thousand miles above the lunar far side before trekking back to Earth. On Artemis III, the first Artemis mission to the lunar surface, Orion will venture to near-rectilinear halo orbit, an orbit balanced between the Earth’s and Moon’s gravity that hangs almost like a necklace from the Moon. The orbit provides access to the Moon’s South Pole, where 13 candidate landing regions have been identified for future Artemis missions.  


Just after 4 p.m. CST, Orion was over 264,000 miles from Earth and nearly 46,000 miles from the Moon, cruising at 1,790 mph.


Watch the latest episode of Artemis All Access to learn more about Orion’s journey so far.


On Wednesday, Nov. 30 at 5 p.m. EST, NASA will host a briefing to preview distant retrograde departure on Thurs., Dec. 1 and how the recovery teams are preparing for entry and splashdown. The briefing will be live on NASA TV, the agency’s website, and the NASA app.
 

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Artemis I Flight Day 16 – Orion Successfully Completes Distant Retrograde Departure Burn


Dec. 1, 2022): On flight day 16, a camera mounted on one of Orion’s solar arrays snapped this image of our Moon as the spacecraft prepared to exit distant retrograde orbit during the Artemis I mission.


Orion has left its distant lunar orbit and is on its return journey home. The spacecraft successfully completed the distant retrograde departure burn at 3:53 p.m. CST, firing its main engine for 1 minute 45 seconds to set the spacecraft on course for a close lunar flyby before its return home.


The burn changed Orion’s velocity by about 454 feet per second and was performed using the Orion main engine on the European Service Module. The engine is an orbital maneuvering system engine modified for use on Orion and built by Aerojet Rocketdyne. The engine has the ability to provide 6,000 pounds of thrust. The proven engine flying on Artemis I flew on 19 space shuttle flights, beginning with STS-41G in October 1984 and ending with STS-112 in October 2002.


The burn is one of two maneuvers required ahead of Orion’s splashdown in the Pacific Ocean on Dec. 11. The second will occur on Monday, Dec. 5, when the spacecraft will fly 79.2 miles above the lunar surface and perform the return powered flyby burn, which will commit Orion on its course toward Earth.


Teams also continued thermal tests of the star trackers during their eighth and final planned test. Star trackers are a navigation tool that measure the positions of stars to help the spacecraft determine its orientation. In the first three flight days of the mission, engineers evaluated initial data to understand  star tracker readings correlated to thruster firings.


A trajectory correction burn is planned for approximately 9:53 p.m. CST today, when Orion’s auxiliary thrusters will fine-tune the spacecraft’s path.


Just after 4:30 p.m. CST on Dec. 1, Orion was traveling 237,600 miles from Earth and 52,900 miles from the Moon, cruising at 2,300 mph.


Images are available on NASA’s Johnson Space Center Flickr account and Image and Video Library. When bandwidth allows, views of the mission are available in real-time.
 

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Artemis I – Flight Day 17: Orion Fine-tunes Trajectory, Downlinks Data, Continues Test Objectives


Orion’s optical navigation camera captured this image of the Moon on flight day 16 of the Artemis I mission. Orion uses the optical navigation camera to capture imagery of the Earth and the Moon at different phases and distances, providing an enhanced body of data to certify its effectiveness under different lighting conditions as a way to help orient the spacecraft on future missions with crew.


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.


Images from the mission are available on NASA’s Johnson Space Center Flickr account and Image and Video Library. When bandwidth allows, live views from Orion are available in real-time.
 

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Artemis I – Flight Day 18: Orion Re-enters Lunar Sphere of Influence


(Dec. 2, 2022) A camera mounted on one of Orion’s four solar arrays captured this image of the Moon on flight day 17 of the 25.5-day Artemis I mission from a distance of more than 222,000 miles from Earth. Orion has exited the distant lunar orbit and is heading for a Dec. 11 splashdown in the Pacific Ocean.


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.


Images from the mission are available on NASA’s Johnson Space Center Flickr account and Image and Video Library. When bandwidth allows, live views from Orion are available in real-time.
 

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Artemis I – Flight Day 20: Orion Conducts Return Powered Flyby


On Dec. 5, 2022, Orion completed the return powered flyby burn, committing the spacecraft to a Dec. 11 splashdown in the Pacific Ocean.


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 a collaboration 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.
 

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