When were the dwarf planets discovered?

Answer 1

The asteroid Ceres was discovered in 1801; the planet Pluto was discovered in 1930.

In 2006, the International Astronomical Union decided to formally define a "planet"; this had never been formally done before. The discoveries of other distant objects beyond Pluto caused the IAU to finally come up with a rule.

According to the new rule, Pluto, Ceres, and Eris (a newly discovered "tenth planet") were all classified as "dwarf planets".

Answer 2

The first dwarf planet to be discovered was Ceres in 1801. However, the classification of dwarf planets was not formally established until 2006 by the International Astronomical Union (IAU). Subsequent dwarf planets like Pluto and Eris were discovered before this classification.

Answer 3

Of the five dwarf planets, as they are classified today, Ceres was the first to be discovered on 1 January 1801 by Giuseppe Piazzi. For half a century it was classified as the eighth planet.

Answer 4

By Giuseppe Piazzi a italian astronomer