Cosmic Exploration · discovery

Pluto

1930 · Clyde Tombaugh

Year
1930

Description

Tombaugh blinked photographic plates for a year looking for a predicted ninth planet. He found one — though far too small to be the object the prediction called for, which was an error.

Discoverer

Referenced by

researcher

Open on the Cosmic Exploration shelf — the interactive card, the filters, and everything alongside it.

From the Discoveries database in Notion, last edited 2026-08-15. This page is the row, rendered by the build; nothing on it is written by hand.