29.11.2022

Artemis I – Flight Day 12: Orion Star Trackers, Reaction Control Thrusters Tested 

art001e000479 (Nov. 24, 2022) – On flight day 9, NASA’s Orion spacecraft captured imagery looking back at the Moon from a camera mounted on one of its solar arrays. The spacecraft is enroute to a distant retrograde orbit around the Moon.

On the 12th day of the Artemis I mission, team members conducted another planned test of the star trackers aboard Orion as it continued along a distant retrograde orbit of the Moon, and began another reaction control thruster flight test. 

Engineers hope to characterize the alignment between the star trackers and the Orion inertial measurements units, both of which are part of the guidance, navigation and control system, by exposing different areas of the spacecraft to the Sun and activating the star trackers in different thermal states. Star trackers are navigation tools that measure the positions of stars to help the spacecraft determine its orientation. The inertial measurement units contain three devices, called gyros, used to measure spacecraft body rotation rates, and three accelerometers used to measure spacecraft accelerations.  

Together, the star tracker and inertial measurement unit data are used by Orion’s vehicle management computers to compute spacecraft position, velocity, and attitude. The measurements will help engineers understand how thermal states affect the accuracy of the navigation state, which ultimately affects the amount of propellant needed for spacecraft maneuvers. Read more about Orion’s guidance, navigation, and control system in the Artemis I reference guide. 

Engineers began a development flight test objective today thatchanged the minimum jet firing time for the reaction control thrustersover a period of 24 hours. This test objective is designed to exercise the reaction control system jets in a different configuration to model how thruster jets will be used for the crewed Artemis II mission. 

Teams also activated and interacted with the Callisto payload, a technology demonstration from Lockheed Martin in collaboration with Amazon and Cisco. Callisto is located in the Orion cabin and will test voice activated and video technology in the deep space environment. 

Monday, Nov. 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, cruising at 1,750 miles per hour. 

To follow the mission real-time, you can track Orion during its mission around the Moon and back, and check the NASA TV schedule for updates on the next televised events. The latest imagery and videos can be found on the Johnson Space Center Flickr. 

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Artemis I – Flight Day 11: Orion Surpasses Apollo 13 Record Distance from Earth

On flight day 11, NASA’S Orion spacecraft captured imagery looking back at the Earth from a camera mounted on one of its solar arrays. The spacecraft is currently in a distant retrograde orbit around the Moon.

On day 11 of the Artemis I mission, Orion continues its journey beyond the Moon after entering a distant retrograde orbit Friday, Nov. 25, at 3:52 p.m. CST. Orion will remain in this orbit for six days before exiting lunar orbit to put the spacecraft on a trajectory back to Earth and f a Sunday, Dec. 11, splashdown in the Pacific Ocean.

Orion surpassed the distance record for a mission with a spacecraft designed to carry humans to deep space and back to Earth, at 7:42 a.m. Saturday, Nov. 26. The record was set during the Apollo 13 mission at 248,655 miles from our home planet. At its maximum distance from the Moon, Orion will be more than 270,000 miles from Earth Monday, Nov. 28.

Engineers also completed the first orbital maintenance burn by firing auxiliary thrusters on Orion’s service module at 3:52 p.m. for less than a second to propel the spacecraft at .47 feet per second. The planned orbital maintenance burns will fine-tune Orion’s trajectory as it continues its orbit around the Moon.

Flying aboard Orion on the Artemis I mission is a suited manikin named after a key player in bringing Apollo 13 safely back to Earth. Arturo Campos was an electrical engineer who developed a plan to provide the command module with enough electrical power to navigate home safely after an oxygen tank aboard the service module of the Apollo spacecraft ruptured. Commander Moonikin Campos is outfittedwith sensors to provide data on what crew members may experience in flight, continuing Campos’ legacy of enabling human exploration in deep space.

Artemis builds on the experience of Apollo. With Artemis, humans will return to the lunar surface, and this time to stay. NASA will use innovate technologies to explore the Moon’s South Pole and more of the lunar surface than ever before using the Gateway space station in lunar orbit along with advanced spacesuits and rovers. NASA will lead the way in collaboration with international and commercial partners to establish the first long-term presence on the Moon. Then, we will use what we learn on and around the Moon to take the next giant leap: sending the first astronauts to Mars.

As of 1:16 p.m., Orion was 252,133 miles from Earth and 52,707 miles from the Moon, cruising at 2,013 miles per hour. You can track Orion via the Artemis Real-Time Orbit Website, or AROW.

Learn more about how Apollo builds on Artemis and how Orion is designed for human missions to deep space.

Quelle: NASA

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Screenshots von Artemis-Live-Stream

Quelle: NASA

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Artemis 1 is a triumph for NASA and the world

NASA’s heavy lift Space Launch System (SLS) has certainly faced criticism. It is too expensive and too complex. The SLS is also not a sustainable rocket for sending people back to the moon.

All of those criticisms are valid. However, NASA’s monster rocket has just sent an uncrewed Orion space capsule around the moon. The launch of the Artemis 1 mission is an eloquent answer to the critics, at least in the short term.

NASA Administrator Bill Nelson must feel especially vindicated. He has been instrumental in birthing the Space Launch System as a result of a “Faustian bargain,” as former NASA Deputy Administrator Lori Garver put it, that also birthed the commercial crew program. Over budget and behind schedule, the SLS finally lifted off, powering a mission to the moon.

A few days later, the Orion spaceship performed a rocket burn that sent it just 81 miles over the surface of the moon. A second burn placed it in a distant retrograde orbit around the moon. Finally, the Orion will initiate two more maneuvers that will send it back to a splashdown just off the coast of California.

With the exception of a few anomalies that NASA describes as “benign,” the Artemis 1 mission has been a resounding success. The mission has already received praise from the White House and Congress. The Biden administration decided to continue the program, first started by President Donald Trump. Congress has continued to fund the effort to return astronauts to the moon. Artemis 1 has vindicated both decisions.

The final milestone that Artemis 1 must achieve to make the mission a complete success is the splashdown. The Orion is scheduled to land in the ocean off southern California on Dec. 11. If the mission ends in a successful splashdown, it will lead to future voyages of discovery. Artemis II will send a crew of four around the moon, the Artemis program’s version of Apollo 8.

Artemis III will be the history-making event, the one that, having occurred, will change the world forever. Humans from the planet Earth will land on the moon and walk upon its surface, preparing the way for the Lunar Base Camp. They will travel to the lunar surface on a SpaceX Starship Human Landing System. NASA officials think that people will be living and working on the moon before this decade is out. The moon will have been brought into the sphere of human activity.

By executing the Artemis I mission, NASA has proven that it can do two things. It has proven that it can actually launch the complex Space Launch System successfully, working through last-minute anomalies that always crop up when operating a new rocket. More importantly, the space agency and its international and commercial partners have proven that it can provide just a hint of the awe and inspiration that the Apollo program gave to the world.

The news media has not yet given Artemis the wall-to-wall coverage that it did Apollo. While NASA’s latest mission has certainly been eclipsed by other topics, at least the media has started to cover the mission to the moon, perhaps slowly realizing that something wonderful has started to happen.

Presuming the Artemis I mission ends with a successful splashdown, how does NASA and its partners sustain the program to send astronauts back to the moon?

First, NASA must get a better handle on operating the Space Launch System. The Artemis I launch suffered several delays because of anomalies inherent in a rocket that was designed as much by politicians as engineers. The space agency should also start to explore cheaper, more commercial alternatives to getting astronauts to the moon and back. Just as the commercial crew system replaced the space shuttle, some future spacecraft should, in the fullness of time, replace the SLS.

Finally, NASA and its partners need to continue to educate the public about the benefits of returning to the moon. Apollo petered out because the space agency and its supporters could not articulate a reason for continuing the first moon program. NASA does return quite a bit to the economy. It would be a great tragedy should the space agency fail to convince the people who pay for its budget that returning to the moon is worth the cost.

Quelle: The Hill