NASA’s Advanced Composite Solar Sail System (ACS3) spacecraft, designed to test a new type of solar sail capable of propelling spaceships at unprecedented speeds, is experiencing unusual tumbling motion in Earth’s orbit. The spacecraft’s attitude control system, responsible for maintaining its orientation, is currently offline, leading to the wobbling. While NASA confirms the tumbling is part of a planned sail deployment sequence, the exact cause and duration remain unclear. The incident has sparked curiosity among space enthusiasts, with the sail potentially visible to the naked eye over the next few weeks.