It's time for Artemis II to break Apollo 13's distance record. What to know about the moon flyby

HOUSTON (AP) — The Artemis II astronauts are already the champions of a fresh new era of lunar exploration. Now it’s time to set a new distance record.

Launched last week on humanity’s first trip to the moon since 1972, the three Americans and one Canadian are chasing after Apollo 13’s maximum range from Earth. That will make them our planet’s farthest emissaries as they swing around the moon without stopping on Monday and then hightail it back home.

Their roughly six-hour lunar flyby promises views of the moon’s far side that were too dark or too difficult to see by the 24 Apollo astronauts who preceded them. A total solar eclipse also awaits them as the moon blocks the sun, exposing snippets of shimmering corona.

“We’ll get eyes on the moon, kind of map it out and then continue to go back in force,” said flight director Judd Frieling. The goal is a moon base replete with landers, rovers, drones and habitats.

A look at Artemis II's up-close and personal brush with another world — our constant companion, the moon.

Apollo 13 holds the distance record from Earth

Apollo 13’s astronauts missed out on a moon landing when one of their oxygen tanks ruptured on the way there in 1970.

With the three lives in jeopardy, Mission Control pivoted to a free-return lunar trajectory to get them home as fast and efficiently as possible. This routing relies on the gravity of Earth and the moon, and minimal fuel.

It worked for Apollo 13, turning it into NASA’s greatest “successful failure.” (For the record, flight director Gene Kranz never uttered “Failure is not an option.” The line is pure Hollywood, originating with the 1995 biopic starring Tom Hanks.)

How Artemis II will surpass Apollo 13

Commander Jim Lovell, Fred Haise and Jack Swigert reached a maximum 248,655 miles (400,171 kilometers) from Earth before making their life-saving U-turn on Apollo 13.

Artemis II’s astronauts are following the same figure-eight path since they are neither orbiting the moon nor landing on it. But their distance from Earth should exceed Apollo 13’s by about 4,000 miles (, 6400 kilometers).

Artemis II’s Christina Koch said late last week that she and her crewmates don’t live on superlatives, but it’s an important milestone “that people can understand and wrap their heads around,” merging the past with the present and even the future when new records are set.

Artemis II astronauts take shifts for prime lunar views

During the flyby, the astronauts will split into pairs and take turns capturing the lunar views out their windows with cameras.

Because they launched on April 1, the rendezvous won’t have as much of the far lunar side illuminated as other dates would have. But the crew still will be able make out “definite chunks of the far side that have never been seen” by humans, said NASA geologist Kelsey Young, including a good portion of Orientale Basin.

They’ll call down their observations as they photograph the gray, pockmarked scenes. There's a suite of professional-quality cameras on board, and each astronaut also has an iPhone for more informal, spur-of-the-minute picture-taking.

Young’s team made lunar geography flashcards for the astronauts to study before the flight. “They’ve practiced for many, many, many months on visualizations of the moon,” she said over the weekend, “and getting their eyes on the real thing, I’m really, really looking forward to them bringing the moon a little closer to home on Monday.”

A total solar eclipse is in store during the moon flyby

The upside of the April 1 launch is a total solar eclipse. The eclipse won’t be visible from Earth — only from the Orion capsule — treating the astronauts to several minutes’ worth of views of the sun's outermost, radiating atmosphere, the corona.

The astronauts will be on the lookout for any unusual solar activity during the eclipse, Young said, and will use their “unique vantage point” to describe the features of the solar corona, or crown.

All four astronauts packed eclipse glasses to protect their eyes.

How long the brief blackout behind the moon lasts

Orion will be out of contact with Mission Control for nearly an hour when it’s behind the moon. The same thing happened during the Apollo moonshots.

NASA is relying on its Deep Space Network to communicate with the crew, but the giant antennas in California, Spain and Australia won’t have a direct line of sight when Orion disappears behind the moon for approximately 40 minutes.

These communication blackouts were always a tense time during Apollo although, as Frieling points out, “physics takes over and physics will absolutely get us back to the front side of the moon.”

It's homeward bound for Artemis II after the moon flyby

Once Artemis II departs the lunar neighborhood, it will take four days to return home. The capsule will aim for a splashdown in the Pacific near San Diego on April 10, nine days after its Florida launch.

During the flight back, the astronauts will link up via radio with the crew of the orbiting International Space Station. This is the first time that a moon crew has colleagues in space at the same time and NASA can’t pass up the opportunity for a cosmic chitchat. The conversation will include both members of the first all-female spacewalk in 2019: Koch aboard Orion and Jessica Meir, on the station.

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