Which dwarf planet is the largest object in the asteroid belt?

Ceres, also known as 1 Ceres, is the smallest dwarf planet in the Solar System but the largest object in the asteroid belt. The asteroid belt is a ring of small and large rocks between the planets Mars and Jupiter. It divides the planets of the Solar System into "inner" and "outer" planets. The inner planets: Mercury, Venus, Earth and Mars, are between the Sun and the asteroid belt. The outer planets: Jupiter, Saturn, Uranus and Neptune, are on the other side of the belt.

The dwarf planet was discovered on 1st January 1801 by the Italian astronomer Giuseppe Piazzi, who named it after the Roman goddess Ceres. Ceres was the goddess of agriculture, harvest, and motherly love. Originally, Piazzi claimed Ceres to be an asteroid, but in 2006, the International Astronomical Union (IAU) upgraded Ceres to dwarf planetary status.

With a diameter of about 950 km (590 miles), Ceres is the largest object in the asteroid belt. It makes up approximately a third of the belt's total mass. Whereas the majority of rocks in the asteroid belt are irregular shapes, Ceres is spherical. Despite its size, Ceres is too dim to see with the naked eye.

On 27th September 2007, the National Aeronautics and Space Administration (NASA) launched the Dawn space probe to explore Ceres and Vesta. The latter is the second-largest object in the asteroid belt, yet is brighter than Ceres. In 2015, Dawn became the first spacecraft to visit a dwarf planet.