Develop a model based on evidence to illustrate the life span of the sun and the role of nuclear fusion in the suns core to release energy that eventually reaches Earth in the form of radiation. [Clarification Statement: Emphasis is on the energy transfer mechanisms that allow energy from nuclear fusion in the suns core to reach Earth. Examples of evidence for the model include observations of the masses and lifetimes of other stars, as well as the ways that the suns radiation varies due to sudden solar flares (space weather), the 11- year sunspot cycle, and non-cyclic variations over centuries.] [Assessment Boundary: Assessment does not include details of the atomic and sub-atomic processes involved with the suns nuclear fusion.]