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This famous Hubble image of the Eagle Nebula made by NASA scientists was called the Pillar of Creation, as it reflects an area where new stars are forming.

Stars come in all sizes, but those about the size of our sun are the most common. Our sun is a huge droplet of plasma that formed when a giant cloud composed almost entirely of hydrogen gathered and involuted.

The fate of a sun is fixed at its birth.

Inside the sun protons and neutrons fuse, producing helium nuclei and giving off energy in the form of light and heat. The size is determined by the amount of hydrogen it was initially endowed with. Its size is a balance of gravity, pulling its elements together and the outward push from the energy produced during fusion. Our sun began with enough fuel to burn for ten billion years. Gradually the amount of helium grows, while the  hydrogen nuclei are consumed. As the store of hydrogen depletes, the balance of forces that determine the sun's size shift, and some day it will expand into a red giant, consuming its planets. At the center of the red giant the helium will gravitate towards the core and helium nuclei will start fusing, producing carbon and oxygen. Eventually the amount of energy produced will change the balance of forces yet again, and the red giant will collapse into a white dwarf, about the size of the earth.

Stars much larger than our sun burn ten times faster than sol. When enough helium accumulates, it forms a core earlier in the life of a mega star, and helium fusion begins. Soon cores of carbon and  oxygen also form at the center, and, eventually, the star develops an iron core. In the end, the giant star collapses on itself and explodes as a supernova. 

Heavy elements like iron, lead, and gold only appeared in the universe when one of these giant stars explodes.

Thus we and everything on earth is made of star dust. This stars legacy is the substance that gave rise to life, and we are connected with another star from the early universe.

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