Moon fly-by sees astronauts regain contact with Earth

Q: Why did the Artemis II astronauts lose contact with Earth near the Moon?

They lost contact because Orion passed behind the Moon, which blocked its radio and laser links to Earth. The blackout was expected and lasted about 40 minutes.

Q: How far did Orion travel, and did it break a record?

Orion traveled farther from Earth than any other human crewed mission. It broke the previous record of 248,655 miles, set by Apollo 13 in 1970.

Q: What did the astronauts see during the lunar fly-by?

They saw the Moon’s far side, including cratered terrain and lava plains, and also witnessed a total eclipse of the Sun from the Moon’s perspective. Nasa said this was the first time such a sight had been seen from that viewpoint.

Q: What kind of photos and recordings did the crew make?

They used several cameras, including two professional digital SLRs, a mirrorless camera, video cameras mounted on Orion’s solar array wings, and smartphones. They also made sketches and recorded audio descriptions of what they saw.

Q: What happens to Artemis II after the Moon fly-by?

The crew will spend several quieter days doing checks and experiments before returning to Earth. The mission ends with a high-speed atmospheric re-entry and a parachute splashdown in the Pacific to test Orion’s heatshield and recovery systems.

Four astronauts on Nasa's Artemis II mission are on their way back home after a dramatic lunar fly-by that saw them travel further from Earth than any other humans.

The crew lost contact with the Earth, as expected, for 40 minutes as they travelled behind the Moon.

With communications re-established, astronaut Christina Koch said: "It's so great to hear the Earth again."

Soon afterwards the spacecraft dipped to within a few thousand miles of the lunar surface and the crew witnessed a total eclipse of the Sun as the Moon blocked out its light - the first time such a sight has been seen from the Moon's perspective.

The Artemis II mission's spacecraft, Orion, broke the record for human travel at about 13:56 EDT (18:56 BST) on Monday, beating a record of 248,655 miles (400,000km) held since 1970 by the Apollo 13 mission.

Canadian astronaut Jeremey Hansen acknowleged the achievement with humility.

"As we surpass the furthest distance humans have ever traveled from planet Earth, we do so in honoring the extraordinary efforts and feats of our predecessors in human space exploration," he said.

As the spacecraft approached and the Moon swelled in its windows, the astronauts began working through a checklist of things to record on its surface, taking images with an array of digital cameras and, as Nasa had briefed, making sketches and recording their own audio descriptions of what they saw.

The spacecraft was not planning to land on the Moon but fly around its far side, the side which is never visible from Earth. Satellites have photographed the far side before, but the astronauts were the first human eyes to see some parts of the far side's surface and its vast craters and lava plains.

The crew's kit included two professional digital SLR cameras – one fitted with a wide‑angle lens to capture the whole scene, another with a powerful zoom to pick out fine detail on the lunar surface – plus a mirrorless camera with a standard‑view lens designed to produce images with a perspective close to that of the human eye.

Small, rugged video cameras mounted on the tips of each of Orion's four solar array wings recorded smooth, continuous views as the spacecraft swept over the Moon's cratered landscape, while each astronaut also carried a smartphone to film and photograph everyday life inside the capsule.

Nasa says it plans to share much of the imagery, either later in the mission or when the spacecraft returns to Earth.

During the six hour flyby, the crew dimmed Orion's internal lights to reduce reflections on the windows and improve their view.

Nasa's science team say the audio will matter as much as the imagery: as the astronauts "say what they see" while looking out, trained human eyes can sometimes pick out subtle colours, contrasts and textures that do not stand out in spacecraft images alone.

Dr Kelsey Young, the agency's lunar science lead, told BBC News that a well trained observer could detect faint shades in the landscape – the nuances of colour, texture and geological features on the far side – that became clearer the longer they stared at the Moon from close up.

"Human eyes and brains are highly sensitive to subtle changes in color, texture, and other surface characteristics," she said.

The night's most nerve-jangling phase came as the Orion craft slipped behind the bulk of the Moon. Its radio and laser connections to Earth were cut off, leaving the four astronauts alone on the lunar far side for about 40 minutes.

Just before this "loss of signal", Pilot Victor Glover had a message for the people of Earth.

"As we prepare to go out of radio communication, we're still going to feel your love from Earth. And to all of you down there on Earth and around Earth, we love you, from the Moon. We will see you on the other side."

For the next 40 minutes, mission controllers, the astronauts' friends and families, and those watching the live stream waited anxiously as the mission clock ticked down to the moment when contact should have been restored.

When the signal finally did flicker back into life there was a long silence before the voice of Christina Koch crackled back to mission control, evoking memories of the Apollo era.

"We will explore. We will build ships. We will visit again. We will construct science outposts. We will drive rovers, we will do radio astronomy, we will found companies. We will bolster industry, we will inspire.

"But ultimately, we will always choose Earth. We will always choose each other".

From about 20:35 (01:35 BST Tuesday) the Sun as seen from the capsule began to change as the Moon moved to eclipse it. What was left was a portion of the Sun's shimmering atmosphere, called the corona, poking out from the lower portion of the Moon. which is usually drowned in glare.

Glover was moved by what he saw: "It is amazing the brightness where the sunset is still bright and you still have a distinct Earth shine."

For Nasa, "Moon Day" was not just theatre. It was about putting the Orion spacecraft through its paces and to see if it could cope for future missions.

Artemis II is a test flight ahead of more ambitious goals, including landing humans on the Moon for the first time since 1972, and ultimately sending humans to Mars.

Sensors on Orion recorded how its power and thermal systems coped for nearly an hour without direct sunlight and with rapid swings in heating and cooling as it moved through the eclipse.

Orion had made its closest sweep past the Moon, endured its spell of isolation, watched an eclipse in the black and then let lunar gravity bend its path back towards Earth.

The crew now face several quieter days of checks and experiments before a final ordeal: a fiery plunge through the atmosphere at nearly 25,000mph and a parachute splashdown into the Pacific that will test the capsule's heatshield and recovery systems.