Pluto discovered discovered http://www.history.com... Pluto Day Pluto discovered last time they searched for the 9th planet More info Pluto discovered More info http://www.history.com/this-day-in-history/pluto-discovered per this website descubierto More info Percival Lowell postulated source 3 Pluto ebruary 18, 1930: Pluto Discovered Percival Lowell postulated discovered confirmed. confirmed. Pluto Day http://www.history.com...