Why have astronomers decided that pluto should be reclassified as a dwarf planet?

what happens to most meteors when they enter earth's atmosphere?

There is a new standard of planets that the IAU set in 2006 and Pluto did not pass it. The new qualification is that a planet must be free of debris around it.

Most meteors are small enough to be burned by friction once it enters the Earth's atmosphere. They are also called 'shooting stars'.

They agreed a new definition of a planets and created "dwarf planets" as a separate type of object. Pluto qualified only as a "dwarf planet", because it is not the dominant object in the neighbourhood of its orbit ...