NASA astronaut Christina Koch, Artemis II mission specialist, peers out of one of the Orion spacecraft’s main cabin windows on Saturday, April 4, 2026, looking back at Earth, as the crew travel toward the Moon.

NASA

Editor’s Note: This article was updated at 5:50 p.m. EDT on Monday, April 6, 2026, to update the times for lunar flyby activities.

Editor’s Note: This article was updated at 1:40 p.m. EDT on Sunday, April 5, 2026, to correct the time for the distance record , and adjust other times for lunar flyby activities.

The first crewed test flight under NASA’s Artemis program is underway. Four Artemis II astronauts are flying aboard NASA’s Orion spacecraft around the Moon and back, as they test how the spacecraft’s systems operate in a deep space environment.

NASA astronauts Reid Wiseman, Victor Glover, and Christina Koch, and CSA (Canadian Space Agency) astronaut Jeremy Hansen lifted off at 6:35 p.m.…