Canvis en el concepte de sistema solar

Our knowledge of the solar system is constantly expanding. Ideas that initially are accurate become uncertain and/or obsolete because they evolve and they need to be revised. The planets of the solar system havent always been the neither the same nor the same number. The concept of planet has also changed. This fact becomes a tool to work in the classroom. Our proposal is based on two texts: The first one, which we date approximately in 1850, presents the Planetary System made up by 23 planets; the second includes resolutions 5 and 6 in which the IAU General Assembly in Prague passed a new definition of planet, on August 24 of 2006