Overview

• Traveling faster than 200 000 km/h, the object’s unbound path through the inner Solar System confirms its origin beyond the Sun’s gravity.
• More than 100 observations, including initial detections by NASA’s ATLAS survey in Hawaii, have helped refine its estimated diameter at 10–20 km.
• A11pl3Z will skim just inside Mars’s orbit before swinging around the Sun in October 2025 and then departing back to interstellar space.
• Once the IAU Minor Planet Center formalizes its status, A11pl3Z will join ʻOumuamua and 2I/Borisov as the third confirmed interstellar visitor.
• Astronomers will continue tracking it through next year and expect next-generation telescopes like the Vera C. Rubin Observatory to increase detections of such objects.