The purpose for which a pedigree chart might be prepared is to identify the pattern of inheritance of a particular trait.
This pedigree chart is created so as to see which traits this new offspring has inherited from its ancestors and which may possibly be transferred onto a new offspring later on in its life. It is formed in order to find patterns of inheritance and see what the most important traits that get inherited are.
A) Earth moon sun
the moon blocks the sunlight from the ground creating a solar eclipse.
This could be the superior and inferior articulate facets