SLS began its slow and deliberate journey to Launch Pad 39B from the Vehicle Assembly Building (VAB) early on January 17 at Kennedy Space Center, marking a major milestone in the agency’s quest to return astronauts to the Moon for the first time in more than half a century.

The 322-foot-tall rocket emerged from the cavernous Vehicle Assembly Building at 7:04 a.m. EST, carried atop Crawler-Transporter 2 for the four-mile trek to the historic launch complex. The combined stack — rocket, Orion capsule, and mobile launcher — weighs approximately 11 million pounds and is traveling at a top speed of just under one mile per hour.