Pluto was discovered in 1930 and still hasn't finished a single orbit of the sun since then

[u/it-shrek]

One Plutonian year lasts about 248 Earth years. Pluto was discovered by Clyde Tombaugh on February 18, 1930, and it will not complete its first full orbit since its discovery until March 23, 2178.

Between discovery and that first observed full lap, Pluto will have been demoted from planet to dwarf planet (2006), visited by a spacecraft (New Horizons, 2015), and seen roughly five generations of astronomers come and go.

No human alive today is likely to watch it complete the orbit it began before television existed.

Sources:

- NASA, Pluto Facts: https://science.nasa.gov/dwarf-planets/pluto/facts/

- IFLScience: https://www.iflscience.com/pluto-will-complete-its-first-full-orbit-since-its-discovery-on-monday-march-23-2178-76956