Calculate Your Planet's

                                             Year Length                                          

This third law will allow you to figure out how long your planet's year will be.


 The Life Cycles of Stars

     As time passes, changes occur in the natural world around us. Some changes are easily noticed, such as flowers going from bud to blossom to the formation of seeds. People and animals have life cycles, moving from birth to maturity and eventually to death.  The seasons change, and every day brings its familiar changes. However, there are other changes that take longer periods of time, and humans do not notice them during their lifetimes.

    Geological events on earth, such as mountain formation or the slow drift of the continents, take place over eons. Changes in climate, vegetation, and the dominant species of animals occur over long periods of time. Scientists find evidence of these changes in the geologic and fossil record. They are not noticed in a single life time.

     However, there are changes that occur on an even slower scale. Astronomers observing the sky notice that even stars have life cycles. Stars are born, mature, change, and die. This page will tell you about the life cycles of stars.

Birth: How Stars Begin to Form