Cosmology 101: The Death of Pluto

Image via BBC

Ladies and gentlemen. We are gathered here today to commemorate the death of one of ‘The Nine’. He has been apart of our family and in our hearts from the first day we stepped into science class in High School. In science class, our teacher, in trying to help us remember The Nine, would use the famous mnemonic :

My Very Educated Mother, Just Showed Us Nine Planets/Potatoes/Pineapples”

M = Mercury

V = Venus

E = Earth

M = Mars

J = Jupiter

S = Saturn

U = Uranus

N = Neptune

P = Pluto

Sad to say, Pluto is no more! He’s not dead, he’s just not recognized as a planet. Astrophysicist Neil DeGrasse Tyson and the International Astronomical Union decided to strip Pluto of its planetary status based on a new definition of planets.

In essence, a planet is a body that dominates its environment. Which means that it should be the largest body in the area it orbits. Pluto’s moon is half the size of the planet. To put that into perspective, think of Earth’s moon being just half the size of Earth.

My biggest concern though is what will become of the mnemonic we’ve cemented in our minds. ‘My Very Educated Mother Just Showed Us Nine ….’ just seems incomplete. I can see an innocent child waiting in vain for you to complete that sentence :(

Au revoir Pluto. Vous allez nous manquer. (Goodbye Pluto. We will miss you)