NASA’s crawler-transporter carries the powerful SLS (Space Launch System) rocket and Orion spacecraft on the Mobile Launcher from the Vehicle Assembly Building to Launch Pad 39B at Kennedy Space Center in preparation for the Artemis II mission on ## Jan. 17 , 2026. Credit: NASA/Brandon Hancock Before NASA sends its astronauts Reid Wiseman, Victor Glover, Christina Koch, and CSA (Canadian Space Agency) astronaut Jeremy Hansen on their Artemis II mission around the Moon, the launch team at NASA’s Kennedy Space Center in Florida and teams across the country will begin counting down about two days before liftoff. A launch countdown contains “L Minus” and “T Minus” times. The “L minus” indicates how far away liftoff is in hours and minutes. The “T minus” time is a sequence of events built into the launch countdown.…