As NASA's Artemis II mission roared to life earlier today, spectators noticed something: shortly after clearing the tower, the massive Space Launch System (SLS) rocket began to tilt.

Instead of piercing a straight line into the sky, it leaned over, tracing a long, graceful arc toward the horizon. To the untrained eye, it looks like a steering error. But actually it is a precision maneuver known as a "gravity turn."