March 28, 2024

NASA Artemis I – Flight Day 12: Orion Tests Star Trackers and Reaction Control Thrusters

View of the Moon seen from ESAs European Service Module that is powering NASAs Orion spacecraft to the Moon and back, on flight day 9 of the Artemis I mission, on November 24, 2022. At the time the spacecraft was en route to a remote retrograde orbit around the Moon. The inertial measurement units contain three gadgets, called gyros, utilized to measure spacecraft body rotation rates, and three accelerometers utilized to determine spacecraft accelerations.
Artists impression of Orion over the Moon.

View of the Moon seen from ESAs European Service Module that is powering NASAs Orion spacecraft to the Moon and back, on flight day 9 of the Artemis I mission, on November 24, 2022. At the time the spacecraft was en path to a distant retrograde orbit around the Moon. Credit: NASA
As Orion continued along a remote retrograde orbit of the Moon on the 12th day of the Artemis I objective, employee carried out another planned test of the star trackers aboard the spacecraft. They also started another reaction control thruster flight test.
Engineers hope to define the alignment in between the star trackers and the Orion inertial measurement systems by exposing various areas of the spacecraft to the Sun and triggering the star trackers in different thermal states. Both of these are part of the navigation, assistance, and control system. Star trackers are navigation tools that measure the positions of stars to assist the spacecraft determine its orientation. The inertial measurement systems include three devices, called gyros, used to determine spacecraft body rotation rates, and 3 accelerometers used to determine spacecraft accelerations.
Together, the star tracker and inertial measurement system information are used by Orions vehicle management computer systems to compute spacecraft mindset, velocity, and position. The measurements will help engineers understand how thermal states impact the precision of the navigation state, which eventually affects the amount of propellant needed for spacecraft maneuvers. Check out more about Orions control, navigation, and guidance system in the Artemis I reference guide.

Artists impression of Orion over the Moon. Orion is NASAs next spacecraft to send out human beings into space.
Engineers began an advancement flight test goal today that changed the minimum jet firing time for the response control thrusters over a duration of 24 hours. This test goal is developed to work out the response control system jets in a different configuration to design how thruster jets will be used for the crewed Artemis II mission.
Teams also triggered and engaged with the Callisto payload, an innovation demonstration from Lockheed Martin in partnership with Amazon and Cisco. Callisto lies in the Orion cabin and will evaluate voice activated and video innovation in the deep space environment.
Monday, November 28, Orion will reach its farthest distance from Earth when it is nearly 270,000 miles from our home planet.
As of 4:30 p.m. CST, Orion was over 264,000 miles from Earth and 45,600 miles from the Moon, travelling at 1,750 miles per hour.
To follow the objective real-time, you can track Orion throughout its objective around the Moon and back, and check the NASA TV schedule for updates on the next televised events.