Pow! Zap! (Big) Bang?! (Introduction)

by David Turell @, Monday, September 27, 2010, 17:45 (5171 days ago) @ Balance_Maintained
edited by unknown, Monday, September 27, 2010, 17:50

Supernovas are much larger than our sun with its 10 billion year lifetime. Being bigger they blow up much sooner. If the potential supernova is 20 times the mass of our sun it will blow up rougly 20 times sooner. Your formula is completely wrong.
> > 
> > http://imagine.gsfc.nasa.gov/docs/teachers/lessons/xray_spectra/background-lifecycles.h... 
> Supernovae is not a type(classification) of a star, it is the action of a larger star that sheds mass once it reaches a certain point in its life cycle. What you are referring to is the Red Giant phase. However, your reference to 20xmass=1/20th of the lifespan is not mentioned anywhere in that article. Do you have a reference for that?-Cannot find exact reference I saw a couple days ago but try these:-http://imagine.gsfc.nasa.gov/docs/teachers/lessons/xray_spectra/background-lifecycles.html--
http://aspire.cosmic-ray.org/labs/star_life/starlife_equilibrium.html-
In contrast with our sun, which is really a main sequence star, massive stars live very short lives, perhaps only millions of years, before they develop dead iron cores and explode as a supernova. The core of a dying massive star may form a neutron star or black hole, but the outermost parts of the exploded star return to the interstellar medium from which they came.-http://www.telescope.org/pparc/res8.html-
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 2000�C to above 30,000�C, and the corresponding colours from red to blue-white. The brightest stars have masses 100 times that of the Sun and emit as much light as millions of Suns. They live for less than a million years before exploding as supernovae. The faintest stars are the red dwarfs, less than one-thousandth the brightness of the Sun. -http://map.gsfc.nasa.gov/universe/rel_stars.html-Since stars have a limited supply of hydrogen in their cores, they have a limited lifetime as main sequence stars. This lifetime is proportional to f M / L, where f is the fraction of the total mass of the star, M, available for nuclear burning in the core and L is the average luminosity of the star during its main sequence lifetime. Because of the strong dependence of luminosity on mass, stellar lifetimes depend sensitively on mass. Thus, it is fortunate that our Sun is not more massive than it is since high mass stars rapidly exhaust their core hydrogen supply. Once a star exhausts its core hydrogen supply, the star becomes redder, larger, and more luminous: it becomes a red giant star. This relationship between mass and lifetime enables astronomers to put a lower limit on the age of the universe.-Quotes are from sites above. I was NOT discussing red giants. Supernovae are of two types. They have their own sequences. Your formula is of no value.-Read in Wikipedia for overall view:-http://en.wikipedia.org/wiki/Stellar_evolution


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