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For many years, kids in science class at school have used cute little mnemonic devices to remember the names of the nine planets of the solar system. For instance “My Very Eager Mother Just Served Up Nutty Peanutbutter” was one that helped kids remember. But in recent years, the list of planets has decreased by one, dropping the “P” from Pluto. Because Pluto has been demoted! 

History of Pluto Demoted Day

Many people are fascinated by outer space and its many mysteries. Earth’s own solar system went through an important and, for some people, very dramatic change in classification in 2006. This was the time when Pluto was demoted from being considered as a full sized planet to being a dwarf planet.

The process of demoting Pluto began in 2005 when a dwarf planet named Eris was discovered in a region outside of Neptune’s orbit in the same belt as Pluto. Because this dwarf planet, Eris, was actually larger than Pluto, it created complications with classification. This was when the International Astronomical Union (IAU) decided officially that Pluto needed to be downgraded from a full sized planet, which took place on August 24, 2006 in Prague, Czech Republic.

This reclassification decision was highly disputed by a number of astronomers, claiming that there were not enough representatives at the convention. Only some 5% of the world’s astronomers voted on the reclassification project. One influential astronomer claimed that if Pluto was reclassified, then Earth, Mars, Jupiter and Neptune all have their own nearby asteroids and this is a contradiction.

Even with the controversy that surrounds the reclassification of this planet to a dwarf planet, Pluto Demoted Day now takes place every year to mark that very occasion. While sad for fans of the former ninth planet of the solar system, Pluto Demoted Day is an important day for our scientific history and is important to remember.

Marking the day itself is a good way to remember Pluto’s former status as a planet, from its discovery in 1930 to its demotion in 2006.

Another related day that can be celebrated for fans of planets or, in this case, dwarf planets, is to celebrate Pluto Day in February.

How to Celebrate Pluto Demoted Day

Show some appreciation and enjoy Pluto Demoted Day by celebrating with some of these delightful ideas:

Learn More About Pluto’s Demotion

Pluto Demoted Day is a great opportunity for study into space and our solar system in general, as well as the history of Pluto itself. Children will be interested to learn about the composition and nature of planets, and Pluto is a fascinating subject for science projects, making it a perfect project for parents and teachers alike to get involved with their kids.

Listen to a Pluto Themed Playlist

Pluto Demoted Day is a great time to create a playlist of tunes and songs that are fun to listen to in honor of this tiny little dwarf planet who has made a huge impact. Enjoy some of these songs when compiling a playlist on Spotify, Apple Music or another platform:

  • Pluto by Bjork (1997)
  • Come Back to Earth by Mac Miller (2018)
  • To Pluto’s Moon by My Brightest Diamond (2008)
  • Pluto by Sufjan Stevens (2017)
  • I’m Your Moon by Jonathan Coulton (2006)

Watch a Space Documentary

Those who want to learn more about not only Pluto, Eris and other dwarf planets, but also about a wide variety of scientific discoveries related to space can take a little time on Pluto Demoted Day to watch some educational shows. Try out some of these titles:

  • NOVA: Pluto and Beyond (2019)
  • The Year of Pluto (2015)
  • The Planets (2019)
  • Exoplanets: Thousands of New Worlds (2019)

Host a Pluto Demoted Day Party

Have a few friends and family members over to celebrate the legacy of this dwarf planet by hosting a gathering for Pluto Demoted Day. Decorate with a space theme, make snacks in the shape of small planets or stars, watch a documentary, or listen to a playlist that centers around the space theme!

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