EVIDENCE OF ACCRETION-GENERATED X-RAYS IN THE YOUNG ...

CHAPTER I
INTRODUCTION
Why should we be interested in star formation? The obvious answer is that in
several ways we owe our existence to stars. One reason is that our very own star, the
Sun, makes its appearance each day in our lives. For humans, the direct, everyday
influence of the Sun comes in the form of literally lighting our path, providing a
warm environment in which we live our lives and giving us a source of power. The
Sun drives Earth’s climate and local weather patterns, indirectly providing us with
necessities like food and water. This seemingly ordinary star is important to every
living creature on Earth in one way or another. This alone is reason enough to ponder
the mysteries of this star as well as the rest of the stars that we gaze at each night
or observe with a telescope.
We also owe a debt of gratitude to other stars, specifically the stars that are
no more – the previous generations of stars that long ago died out even before our
solar system began to take shape. These stars forged the heavier elements in the
nuclear furnaces of their cores or in the explosive processes that took place when they
died. At the ends of their lives, they either obliterated themselves in the spectacular
cataclysms of supernovae or swelled into large planetary nebulae of sublime beauty.
In their death throws, they expelled into space the building blocks that ultimately
led to our existence: the oxygen that we breathe, the phosphorus that forms the
backbone of our DNA, and the silicates that form the crust of our planet. All life
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