In grade school I learned “My Very Educated Mother Just Served Us Nine Pizzas.” This served me well and good for decades until they decided to muddy the water with this whole dwarf planet business.
So what’s a better one with these four other additions?
Edit: Bah, that should be “mnemonic”.
My Very Educated Mother Just Served Us Nachos
Did you forget the correct spelling? 
There are lists where I can see the point in a mnemonic, but this isn’t one of them. It’s not like anyone goes through an extended stage of having a hard time learning the names of the planets. The Firebug knows most of their names at the age of four and a half, and I remember knowing them all (including former planet Pluto), their order from the sun, and the number of then-known moons of each one, when I was six.
Without Pluto it’s “My very extroverted maid just served us naked.”
I learned “M VEM J SUN P” pronounced “Em Vem Jay Sun Pea”
But not everyone thinks like you and I think it’s rather silly to suggest that people don’t need mnemonics for things that you don’t need them for. I’m sure you might have little memory tricks that others think are silly or unnecessary, but it would be rather bizarre to judge you on that.
Perhaps unsurprisingly, I like mnemonics, and this one is useful because it’s very easy to remember and simultaneously contains not only the names but the order of the planets without having to learn those facts separately. I remember random things from school over the years that I never have to work with or use ever again - because I created a good enough mnemonic that 10, 15 years later I can still recall and apply.
Many Very Early Men Ate Juicy Steaks Using No Plates.
Ate - is for the asteriod belt between Mars and Jupiter.
Plates - is for Pluto. If it was a planet when i learned about planets, it’s still a planet god damn it! I’m not letting this new fangled lurnin tell me different.
My Never Educated Mother Offers Nachos In Cups.
When I was a five I had A Child’s Introduction To Outer Space, which included a song called The Wandering Stars.
*Mercury
Venus
Earth and Mars
Jupiter, Saturn, Uranus
Neptune and Pluto!
The wandering stars *
I played it incessantly (on my little ‘suitcase-style’ record player), and it drove my older sister nuts. But she got an answer right on a test once, because the song was firmly lodged in her head. 
Somehow this Saved By the Bell episode has stuck in my head all of these years:
“Meh-vem-juh-sunp.”
In the 1950s I learned the planets from this song from a popular children’s record, music by Raymond Scott: Raymond Scott - By Rocket To The Moon (good sound quality) - YouTube
Interestingly, there are women on the first rocket to the Moon!
My very educated mother just served us nothing.
I like the maid one better.
I don’t use mnemonics, I just make up songs. You should really pity my wife, as she has to hear them. I’m personally proudest of a song I wrote for the Salem Witch Trials…for my upper division history class.
Mnemonics!, Vicullum Entreated. Make Jumbled Sentences Up Now (Please)
I learned a slight variation on these, based on a noenclature that seems now to have been abandoned.
Earth = the world we’re living on. If you’re writing a SF story set on Gamma Velarum II, “Where on Earth…?” is still valid. The planet our species evolved on, where we all still live as of now, is the Latin for Earth, Terra, as a proper name. Likewise the bright globe in the sky during the daytime is the sun; Earth’s Sun, the single star 4.3 light years from the Alpha Centauri complex. is Sol, a proper name. And the satellites of said planet are its moons, our own being named Luna.
Mr Vorlon Expects More Juicy Satire Using Nouns Please.
I think the OP was calling for the new mnemonic to include Ceres, Haumea, Makemake and Eris. So in order, I think that would be: M V E M J S U N C P H M E
Ceres is between Mars and Jupiter. So that would be MVEMCJSUNPHME. And I’m not sure of the order of H, M, and E.
Here’s an attempt.
“My very energetic mother cooks juicy sauces now. Pity her meal eaters!”
I learned it as:
“My Very Elderly Mother Just Shot Uncle Ned’s Parrot”
A quick adjustment would make it homocide rather than bird-murder.
