Pluto Day 2023 is observed yearly on February 18 to mark the 1930 anniversary of Pluto’s discovery.
Pluto was named after the Roman deity of the underworld and on the name of the founder of the observatory where it was discovered.
The International Astronomical Union reclassified it as a ‘dwarf’ planet because it does not match the standards for a full-sized planet and is only one-third the size of the earth.
The planet was discovered by American astronomer Clyde Tombaugh in 1930 and until 2006,
was considered one of the nine planets in the solar system, along with Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
The American astronomer Clyde Tombaugh (born 4 Feb 1906) discovered Pluto on 18 Feb 1930,
by comparing photographic plates taken 23 & 29 Jan, at the Lowell Observatory, in Flagstaff, Arizona. He died 17 Jan 1997 and since then this day is called the Pluto Day.
Pluto has five known moons: Charon, the largest, whose diameter is just over half that of Pluto; Styx; Nix; Kerberos; and Hydra.
The majority of Pluto’s atmosphere is reportedly composed of nitrogen gas.
Pluto is 40 times further from the sun than the earth, which causes its orbit to be sluggish
; it requires 6.4 Earth days or 153.3 hours to complete one round.