https://www.space.com/asteroid-hygiea-may-be-smallest-dwarf-planet.html
The asteroid Hygiea may qualify as a dwarf planet — and it could steal the title of the smallest dwarf planet in the solar system!
Astronomers have captured high-resolution imagery of Hygiea, the fourth largest rock in the Asteroid Belt. And low and behold, Hygiea is spherical in shape. That’s a pretty important dwarf-planet marker, and the only one Hygiea was missing until now.
Asteroids boast a variety of shapes, but the rounded shape of dwarf planets shows that they had enough mass for its own gravity to pull it into this round shape. Hygiea already met the other requirements for dwarf-planet classification since it orbits the sun, is not a moon orbiting another planet and has not cleared other objects out of its own orbit.
