SUN AND EARTH

The sun is going to destroy the earth.  Without the sun, however, no life of any sort would exist. It warms our world and provides the energy all living things need to grow.  In the absence of solar energy, Earth would be a dead and barren place.  With it, plants and animals thrive, both above and below the surface of the ocean.
 
The galaxy in which our solar system is located is one of millions of galaxies within our universe.  Our sun is one of billions of stars within our galaxy.  Around this sun rotate some eight or nine planets.  Earth is the only one capable of sustaining life.  On all of the others, temperatures are either too hot or too cold, and their atmospheres are inhospitable or non-existent.

There is a relatively narrow thermal band within which organic life can flourish.  Above a couple of hundred degrees and below a hundred degrees Fahrenheit, very little, if anything, can stay alive.  Should a cataclysmic event occur that would make the Earth significantly hotter or colder, all flora and fauna would be wiped out.

Earth was not always teeming with life.  After it came into being, billions of years elapsed before its surface was stable enough for living cells to generate and propagate.  In addition, a million or so years of continuous rain were needed to produce the global ocean from which continents would eventually emerge.  The energy provided by the sun was a necessary ingredient for living things to develop and reproduce.  Sea life relies on nutrients that are made possible by the sun’s rays. 

Before the earth acquired its current inclination, there were no seasons.  The areas adjacent to the equator were hot all year.  Temperate parts of the world had little variation in temperature.  The poles retained a continuous coverage of ice and snow. 

Due to the sun’s gravitational tugging, the earth gradually shifted its orientation, so that portions of the world were slightly closer to the sun and other parts slightly further away as the earth revolved around its life and death giving star.  This produced the seasons we know today.  In certain latitudes, such as Europe and most of the United States, spring, summer, autumn and winter follow each other with totally predictable regularity.  In other parts of the globe, hundreds of millions of people live in regions that only have two seasons, wet and dry, and have never seen snow.