The historic Artemis II launch of the second mission under NASA's multibillion-dollar Artemis program is set to take place on April 1 at the Kennedy Space Center near Cape Canaveral, Florida, with four astronauts expected to be sent towards the moon's orbit. The launch window for Artemis II is limited to specific dates and hours due to what's called an "orbital window" which can only be shortened due to Earth's rotational motion. If bad weather or other issues arise, NASA may attempt another two-hour launch window between April 2 and 6 and also on April 30. The mission's launch window is subject to various constraints based on the type of space vehicle launching and where it's intended to go, and NASA has several backup launch opportunities.