On August 24, 2006, prompted by the earlier discovery of a similar and even larger Kuiper Belt object named Eris beyond Pluto, scientists voted on a new definition of the word planet that would deny both of them its use.
When Pluto was downsized to the status of dwarf planet, admirers stuck notes and tokens (a folded crane, some paper flowers) to the former ninth planet's plaque at the Voyage Scale Model Solar System. There's a picture in my astronomy textbook of this and, leaning in close, you can just barely read some of the eulogies.
Rest in peace, Pluto, says one note.
Pluto will always be a planet in my heart, adds another.
My favorite, a large sheet of paper, reads: We'll miss you, signed Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.