Understanding how stars evolve requires both observation and ideas from physics

Understanding how stars evolve requires both observation and ideas from physics

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Understanding how stars evolve requires both observation and ideas from physic s Stellar evolution – how stars are born, mature and die or how stars form and change during that life spa Because stars shine by thermonuclear reactions, they have a finite life span What are the ingredients needed for the creation of a star? Interstellar gas and dust pervade the Galaxy Interstellar gas and dust, which make up the interstellar medium , are concentrated in the disk of the Galaxy Clouds within the interstellar medium are called nebulae There are three types of nebulae Dark nebulae are so dense that they are opaque. They appear as dark blots against a background of distant stars. An example is the Horse-Head Nebula.
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Unformatted text preview: Emission nebulae , or H II regions , are glowing, ionized clouds of gas and dust grains . Emission nebulae are powered by ultraviolet light that they absorb from nearby hot stars. Recombination the process in which free electrons and free protons combine to form Hydrogen also generates light in the visible spectrum. Reflection nebula e are produced when starlight is reflected from dust grains in the interstellar medium, producing a characteristic bluish glow. Interstellar Extinction the process in which the intensity of light from distance stars is reduced as it passes through material in interstellar space. Interstellar Reddening...
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This note was uploaded on 12/15/2011 for the course AST AST1002 taught by Professor Emilyhoward during the Fall '10 term at Broward College.

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