Japan's groundbreaking Hayabusa2 probe is gearing up for a daunting journey as new data reveals its next target asteroid is significantly smaller and spinning much faster than previously thought.

After successfully collecting samples from the asteroid 162173 Ryugu in 2018 and returning them to Earth in 2020, Hayabusa2 was set on an extended mission toward the asteroid 1998 KY26, expected to reach its destination in 2031. However, this mission was already complex, involving a high-speed flyby of another asteroid, 98943 Torifune, which posed a challenge given Hayabusa2’s fixed-camera setup.

New observations have shown that instead of the anticipated 30-meter asteroid, KY26 measures only about 11 meters across. To complicate matters further, it spins much faster—every five minutes instead of the previously estimated ten. Olivier Hainaut from the European Southern Observatory (ESO) notes this realization enhances both the intrigue and difficulty of the mission.

Using the advanced Very Large Telescope in Chile, along with data from other global observatories, scientists have fine-tuned their understanding of this tiny asteroid. The rapid rotation and smaller size raise questions about how Hayabusa2 will execute its landing plans, which originally included firing a tantalum projectile into KY26's surface.

Scientists are eager to observe KY26 further, although they will have to wait for techniques using the James Webb Space Telescope until 2028. If Hayabusa2 can successfully rendezvous with this petite asteroid, it will mark a historic first for space missions—a direct encounter with an object so small.

Astronomer Toni Santana-Ros from the University of Alicante emphasized the remarkable nature of this mission: the asteroid's size is nearly equal to that of the spacecraft itself. He stressed the importance of these methods not only for future asteroid explorations but also for potential asteroid mining and planetary defense strategies.

Hainaut pointed out the critical implications of this research, particularly concerning hazardous asteroids, as they now know they can accurately characterize even the tiniest threats that could impact Earth. With these investigations, the mission promises to unlock new potentials for keeping our planet safe.