HOUSTON—Following a record-setting, seven-hour pass beyond the far side of the Moon, NASA’s Artemis II astronauts returned into the gravitational sphere of Earth April 7 as they continued a free-return trajectory that will bring their nine-day mission to a close with a splashdown in the Pacific Ocean on April 10.

Prior to the crew waking up to begin their seventh day in space, the first images and recorded audio notes from their science observations during the lunar flyby were transmitted back to Earth for analysis.

The downlink, much of which was via an optical communications link, included pictures of the lunar terrain, showing color, brightness, surface textures and other features intended to give scientists a better understanding of the composition and evolutionary history of the Moon. Some of the far-side features were seen by human eyes for the first time, as the Artemis II Orion spacecraft soared 4,000-6,000 mi. beyond the lunar surface, a span that far exceeded the distance of the Apollo capsules’ orbits during the agency’s first forays to the Moon between 1968-72.

“What you did yesterday really made a difference scientifically,” Kelsey Young, the Artemis II lunar science lead, radioed to the astronauts April 7. “Our whole lunar science team and the broader science community have been pouring out positive feedback and gratitude.”

The observations by Orion astronauts Reid Wiseman, Victor Glover and Christina Koch, all with NASA, and Canadian Space Agency astronaut Jeremy Hansen included 4-6 bright flashes from micrometeorites that were visible during the final hour of the flyby when the Sun was eclipsed by the Moon.

“I don’t know if I expected to have the crew see any on this mission,” Young told reporters April 7. “I was not in the science evaluation room [at the time], but I heard there were audible screams of delight.”

With the  optical communications link, NASA was able to download 20 gigabytes of data in a little more than 45 min. “That’s orders of magnitude more than we get via our S-band telemetry system,”  flight director Rick Henfling told reporters. “Optical comm has been working really well, and hopefully we can take what we learned on Artemis II and expand its operational capability and implementation for future missions.”

The Orion capsule, named Integrity, left the Moon’s sphere of gravitational influence and fell back in the gravitational embrace of Earth at 1:23 p.m. EDT when Integrity was 41,072 mi. from the Moon. The transition was a seamless phase of the capsule’s “free return” trajectory provided by orbital mechanics, rather than chemical propulsion.

The Artemis II mission lifted off  April 1 from NASA’s Kennedy Space Center. Following a 25-hr. checkout in high-Earth orbit, Orion’s European Space Agency-provided service module performed a 5 min. 50 sec. engine burn to begin the eight-day loop around the Moon and return to Earth. Integrity’s splashdown off the coast of San Diego on April 10 is expected at 8:06 p.m. EDT.

Integrity’s closest approach to the Moon—4,067 mi. — occurred at 7:02 p.m. EDT April 6 with the ship flying 3,138 mph relative to the lunar surface,

The first of three planned thruster firings to tweak Orion’s return trajectory was expected about 9 p.m. on April 7.

Earlier in the day, Wiseman, Glover, Koch and Hansen participated in a ship-to-ship call with astronauts aboard the International Space Station (ISS) to discuss their lunar flyaround.

“We know how fortunate all of us are to come up here and look down at the Earth from above. Every astronaut who comes to space remarks on that. We really wanted to hear how different that felt now from your new perspective around the Moon,” astronaut Jessica Meir radioed to the Artemis II crew from aboard the ISS.

“The thing that changed for me looking back at Earth was that I found myself noticing not only the beauty of the Earth, but how much blackness there was around it. It just made it even more special,” Koch replied.

“It truly emphasized how alike we are, how the same thing keeps every single person on planet Earth alive. We evolved on the same planet. We have some shared things about how we love and live that are just universal, and the specialness and preciousness of that is really emphasized when you notice how much else there is around it,” she said.

On a lighter note, Koch told Meir, “Jessica, I always hoped we would be in space again together, but I never thought it would be like this.”

The women flew together on the ISS from September 2019-April 2020.

At the time of the ship-to-ship, the ISS was orbiting 267 mi. above Earth south of Africa, and Orion was 231,793 mi. away from Earth.

Quelle: AVIATION WEEK

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How the Artemis II crew trained to observe and photograph the moon: A NASA science team geologist explains

The Artemis II crew has now broken the record — previously held by Apollo 13 — for the farthest distance any humans have ever travelled from Earth. The crew also completed a flyby of the moon’s far side and sent back some amazing images of the lunar surface.

I am a professor, an explorer and a planetary geologist, specializing in the study of meteorite impact structures. I am also a member of the First Artemis Lunar Surface Science Team and have been supporting NASA in developing the geology training for Artemis astronauts.

The flyby was particularly exciting as it offered a stunning new perspective of the lunar surface. It also provided the first operational test of a new science team and evaluation room at Mission Control in NASA’s Johnson Space Center in Houston, Texas.

And it was fantastic to see the Artemis II crew conduct observations and take photographs of geological landforms on the moon’s surface — putting their training with me at the Kamestastin Lake impact structure, on the territory of the Mushuau Innu First Nation in northern Labrador, into practice.

A new view of the moon

Unlike the Apollo missions, that orbited at approximately 110 kilometres above the surface of the moon, Artemis II was at a much higher altitude — around 6,545 kilometres above the lunar surface.

This greater distance allowed the crew to view the moon as a full disk, including regions near both the North Pole and South Pole.

The moon, viewed from Earth and by Artemis II crew. T marks the Tycho crater; O marks the Orientale crater. (G. R. Osinski using NASA images

The crew was also able to take targeted photographs of various geological landforms on the lunar surface as part of the Artemis II science program. One of the primary goals of these investigations is to inform future missions, including the planned first journey back to the lunar surface with Artemis IV as soon as 2028.

A new science team

One of the highlights of NASA’s livestream during the mission has been the direct conversations between two good friends: Canadian astronaut Jeremy Hansen and science officer Kelsey Young.

Science officers are the senior flight controllers responsible for lunar science and geology objectives during Artemis missions.

They act as the main interface between the wider Mission Control team and the Artemis II science team, which is located in a totally separate room called the Science Evaluation Room (SER).

Both science officers and the evaluation room are brand new for NASA’s Artemis program; they did not exist during the Apollo program.

We have been developing the structure and defining roles in the SER for the first Artemis mission to the moon’s surface. But there is nothing like a real mission to test and refine how the science team should work.

Artemis science officers, from left, Kelsey Young, Trevor Graff, and Angela Garcia stand at the new SCIENCE console in the Mission Control Center at NASA’s Johnson Space Center in Houston.(NASA/Josh Valcarcel)

A crash course in lunar geology

If you listened in to NASA’s livestream and heard any of the geological descriptions the astronauts were giving, I hope you were impressed — I certainly was!

Their knowledge is a testament to the geology training that NASA has provided the crew in the months and years since they were selected for the Artemis program.

Artemis II Pilot Victor Glover, Commander Reid Wiseman, and Mission Specialist Jeremy Hansen configure their camera equipment shortly before beginning their lunar flyby observations. (NASA)

First, the crew participated in a crash course in lunar geology called “Lunar Fundamentals.” This weeklong, classroom-based training offered them the basics to understand lunar geology and the processes that shape the moon’s surface — primarily impact cratering and volcanism.

However, as somebody who has been teaching for more than 20 years, I know the best place to learn about geology is in the field. That’s why NASA also took the Artemis astronauts to a series of field sites in the United States, Iceland and Canada.

Early in their training, in September 2023, three of the crew members — Hansen, Christina Koch and back-up crew Jenni Gibbons — undertook geology training at the Kamestastin Lake impact structure in northern Labrador. Then the entire crew travelled to Iceland in August 2024.

Kamestastin Lake training expedition

I was honoured to play a leading role in the Kamestastin Lake training. This location was chosen because it offers a similar landscape to the surface of the moon.

Gordon Osinski (centre) explains the processes that formed the 28-kilometre diameter Kamestastin Lake impact structure to Canadian Space Agency astronauts Jeremy Hansen (left) and Jenni Gibbons (right). (Canadian Space Agency)

The Kamestastin Lake crater was formed approximately 35 million years ago by the impact of an asteroid between one and two kilometres in diameter. Not only are rocks like breccias and impact melt rocks produced by the asteroid’s impact well preserved here, but the crater also formed in a rock called anorthosite — the exact same rock that makes up the lunar highlands.

In addition to participating in the geology training itself, I was largely responsible for the logistics for this expedition.

Kamestastin is in a remote part of northern Labrador, so we flew in via Twin Otter aircraft and established a temporary base camp. From tents to pots and pans and food for 16 people, there was a lot to take care of. We then used zodiac boats to travel around the crater.