Such "countdown demonstration tests" have traditionally taken place shortly before launch with the rocket and crew ship ...

A major step toward launch day is complete as NASA's Artemis II astronauts ran through a countdown demonstration test.

The "America 250" logo commemorates the upcoming 250th anniversary of the signing of the Declaration of Independence.

NASA’s launch and mission teams, along with the Artemis II crew, completed a key test Dec. 20, a countdown demonstration test, ahead of the Artemis II flight around the Moon early next year.

NASA’s Artemis II crew boarded the Orion spacecraft on December 20, 2025, for a countdown demonstration test, rehearsing launch-day procedures at Kennedy Space Center’s Vehicle Assembly Building.

NASA’s Artemis II crew completed a launch day rehearsal at Kennedy Space Center, practicing countdown procedures, spacecraft boarding and system checks ahead of their 2026 lunar orbit mission.

The Space Launch System rocket's RS-25 engine was fired up for the “final round of certification testing ahead of production ...

NASA/Adeline Morgan Santa Claus (NASA engineer Guy Naylor) poses with NASA's Artemis II Orion spacecraft and SLS (Space ...

HANCOCK COUNTY, Miss. (WLOX) - NASA and L3Harris Technologies successfully conducted a full-duration hot fire test of a second RS-25 engine at Stennis Space Center in Hancock County. The engine will ...