Life Cycle of Stars
What is a star?
A star is a luminous globe of gas producing its own heat and light by nuclear reactions (nuclear fusion). They are born from nebulae and consist mostly of hydrogen and helium gas. Surface temperatures range from 2000C to above 30,000C, and the corresponding colors from red to blue-white.
Life Cycle of Stars Compared to Humans
A celestial object in a late stage of star formation in which the central condensation resulting from the collapse of a dense, interstellar cloud core has become a sphere that is opaque so that it has a luminous surface like a star, but has yet to sustain nuclear fusion of hydrogen in its core.
Main sequence stars are stars that are fusing hydrogen atoms to form helium atoms in their cores.
The Origin of the Elements
Elements are formed through Nuclear Fusion. Nuclear fusion is a nuclear reaction in which two light nuclei (such as hydrogen) combine to form a heavier nuclei (such as helium). The process releases excess binding energy from the reaction, based upon the binding energies of the atoms involved in the process. The formation of helium from hydrogen is an example of Nuclear Fusion.