The four astronauts aboard NASA's Artemis II mission broke the record for the farthest distance from Earth ever traveled by humans on Monday, surpassing a milestone set more than half a century ago by the Apollo 13 crew in April 1970.

The record fell at 1:57 pm Eastern Time, as the Orion spacecraft exceeded the 400,171-kilometer mark set by the Apollo 13 mission. The Artemis II crew reached their maximum distance of 406,771 km from Earth at approximately 7:02 pm ET, according to NASA. This milestone places the crew 6,616 km farther from Earth than the Apollo 13 mission.

The four crew members — NASA Commander Reid Wiseman, Pilot Victor Glover, Mission Specialist Christina Koch and Canadian Space Agency Mission Specialist Jeremy Hansen — have completed the mission's lunar observation period and begun the return trip home aboard the Orion spacecraft. Orion will exit the lunar sphere of influence at approximately 1:25 pm on Tuesday.

The mission lifted off from Kennedy Space Center in Florida on Wednesday, beginning a 10-day journey. The crew spent approximately 25 hours in Earth orbit before Orion departed on Thursday evening. Early Monday, they entered the lunar sphere of influence, where the Moon's gravitational pull exceeds that of Earth.

During the flyby of the Moon, the spacecraft reached its closest approach to the Moon, passing within 6,550 kilometers of the lunar surface. The lunar observation period lasted nearly seven hours, during which the astronauts had the opportunity to study the Moon's terrain, including features of the far side that are invisible from Earth and have never been observed by human eyes.

As the spacecraft passed behind the Moon from Earth's perspective at approximately 6:44 pm ET on Monday, the crew experienced a communications blackout with mission control. The blackout, which was expected as the lunar surface blocks the radio signals from an Earth-based communications system, lasted about 40 minutes.

Like Apollo 13, Artemis II follows a free-return trajectory around the Moon. The Apollo 13 crew was forced onto that path after an oxygen tank rupture aborted their planned lunar landing in 1970.

The Artemis II mission does not include a lunar landing. The crew is expected to return to Earth on Friday evening, splashing down in the Pacific Ocean off San Diego, California.

The Artemis II mission aims to demonstrate a broad range of capabilities required for deep space exploration, including validating Orion's life-support systems and allowing astronauts to practice operations critical to future lunar missions.

It marks NASA's first crewed flight under its Artemis lunar exploration program, which was announced in 2019 with the original goal of landing astronauts on the Moon by 2024. NASA conducted Artemis I, an uncrewed lunar-orbiting mission, in November 2022.

In February, NASA revised the Artemis program timeline, inserting an additional mission and pushing the crewed lunar landing back from 2027 to 2028. Under the updated plan, Artemis III will focus on testing systems and operational capabilities in low Earth orbit in 2027, ahead of the Artemis IV lunar landing mission in 2028.