After its flyby of the Moon, Orion is preparing to join its retrograde orbit scheduled for Friday. It will move away from the Moon by several tens of thousands of kilometers, which will allow NASA and ESA to ensure that this vehicle is suitable for human spaceflight. During its closest approach to the Moon, several dozen images were acquired.
Unsurprisingly, the overviewoverview of the MoonMoon by the Orion vehicle went off without a hitch. The spacecraft, piloted from Earth, passed just 128 kilometers from the surface of the Moon! At this distance, the Orion models were able to enjoy a beautiful panorama that very few humans have had the opportunity to contemplate.
This low-hanging land closer to the Moon was obviously not a joke by NASA to please its models. It was only intended to take advantage of the strength of gravitygravity moon to help OrionOrion to bounce back to orbitorbit far retrograde. This is different from the one used during the program ApolloApollowhere the craft and its crew had a more circular orbit and much closer to the lunar surface.
But, as strong as it was, this force was not enough to get Orion where NASA wanted it to be. During its passage behind the Moon — during which communications radioradio between Orion and Earth, and vice versa, were impossible for 34 minutes — Orion performed one of the main maneuvers of his mission. While it was some 530 kilometers from the Moon and flying at more than 8,000 km/h, the main engine of the European service module ignited for 2 minutes and 30 seconds in order to accelerate the machine and achieve the targeted far retrograde orbit. Once again, the maneuver went well.
However, to reach this retrograde orbit, a second ignition of the main engine will be necessary. It will take place on Friday, November 25 and will bring Orion as far as 92,134 kilometers from the Moon, which will also be its farthest point from the Moon. As for Orion’s greatest distance from Earth, it will be reached on Monday, November 28 at 3:05 p.m. CST, at over 432,108 kilometers.
This far retrograde orbit is said to be distant » in the sense that it is very far from the surface of the Moon, and ” retrograde » because Orion will travel around the Moon in the opposite direction as the Moon travels around the Earth.
A week to verify that Orion is suitable for human spaceflight
The absence of astronauts on board Orion will allow the vehicle to remain in this orbit for several days, which should allow NASA and ESA to learn how it reacts in an environment so far from Earth and from the Moon in order to verify its ability to carry out manned flights within the framework of the Artemis program but also to learn and prepare for more distant trips to Mars and asteroids.
Concretely, since its launch the vehicle has been tested inside its flight envelope, in order to see under what conditions and how it can operate in various configurations. The propulsion system of theEuropean service module (ESM) is at the heart of these tests and the maneuvers necessary to bring Orion into this retrograde orbit are scrutinized with great care. Verification of the performance and correct operation of the propulsion system, which are one of the main objectives of Artemis 1, are not the only ones. Guidance, navigation, communication, thermal control and a host of other systems and subsystems are also tested and monitored to ensure the vehicle is ready for its future manned missions.
Orion’s return to Earth is scheduled for December 11.
This flyby of the Moon is an opportunity to introduce you to the book Apollo Remastered (Oak Editions) by Andy Saunders, science writer and one of the world’s leading restoration specialists digitaldigital images from NASA. Andy Sanders has selected and digitally reworked 300 of these images, many of which are unpublished, which trace the history of all the missions of the Apollo program; they are presented for the first time in this book. The result is stunning.
Article of Daniel ChristianDaniel Christian published on 21/11/2022
The Orion spacecraft is completing its approach to the Moon and is about to make a first flyby less than 130 kilometers above the surface. During this flyby, the spacecraft will carry out its maneuvers to take the road to a retrograde lunar orbit. We give you the addresses to follow this event.
As of this writing, Orion is less than 15,000 kilometers from the Moon and moving at almost 450 km/h (280 mph). The flyover is scheduled for today, November 21, at 1:30 p.m. Paris time. Starting at 1:44 p.m., the spacecraft’s European service module will turn on its main engine while the closest passage to the surface will take place at 1:57 p.m., at an altitude of 128 kilometers (80 miles). You can follow his movements live on Nasa-TV Or on Tracking’s official website.
Artemis I, closest to the Moon. © Nasa
However, Orion will not be in direct contact with Earth for some time: between 1:25 p.m. and 1:59 p.m., the ship will be behind the Moon in relation to us, and will therefore be left to its own devices. This is the importance of the test maneuvers, which must be used to qualify the vessel, in particular for the first manned mission Artemis II.
Minor technical issues
Following the great success of the SLS launch that propelled it into space, the Orion spacecraft successfully completed the three planned orbit correction maneuvers during its route to the Moon. However, the NASA teams have noted a few problems, considered minor thanks to the various redundancies: one of the trackers ofstarsstars (star tracker) is not working properly, and neither is a power supply subsystem (using solar panels). Teams work there.
Orion’s maneuvers that will be carried out during this first lunar flyby will help him land on a trajectory of transittransit. It is only at the end of this transit, on November 25, that the ship will place itself in retrograde lunar orbit.