ESO Says That The Asteroid Hygiea Could Be A Dwarf Planet

ESO astronomers have used the SPHERE instrument on the Very Large Telescope to look at the asteroid called Hygiea. The observations have shown that Hygeia could be classified as a dwarf planet. The object is said to be the fourth-largest asteroid in the belts behind Ceres, Vesta, and Pallas.Hygiea is special and may take the crown from Ceres as the smallest dwarf planet in the solar system. The ESO team says that Hygiea meets three of four requirements to be classified as a dwarf planet. Those include that it orbits the sun, it's not a moon, and it hasn't cleared the neighborhood around its orbit as a planet would.

The last of the requirements is that it has enough gravity to pull it into a roughly spherical shape. This is where the SPHERE instrument came in and using it; the team was able to determine that Hygiea is nearly spherical. The instrument also measured the diameter of Hygiea, putting it at just over 430km.

Pluto has a diameter of close to 2400 km, while Ceres is close to 950 km in size. The team didn't find the expected large impact crater on its surface. The crater was expected to be found and to have resulted in from the impact that created Hygiea. It does have two impact craters, but neither is large enough to have created Hygiea.

The team has estimated that Hygiea's spherical shape and the large family of asteroids are likely the results of a major head-on collision with a large projectile of a diameter between 75 and 150 km. The violent impact is thought to have happened about 2 billion years ago.