Pluto did not blow up. This myth is one of several that have emerged since the International Astronomical Union designated Pluto as a dwarf planet under new labeling guidelines. Schools have adapted by teaching students that the solar system has just eight planets instead of the previously taught nine.
The 2006 change resulted in Pluto being too small to meet the criteria for a planet. Prior to 2006, any large celestial body that orbited the sun was considered a planet. Though Pluto still meets this standard, it also carries small elements called planetesimals during its orbit. The eight remaining planets in the solar system do not.