Thursday, February 9, 2012

Can an average star become a neutron star?

The whole question is:



Could an average star, such as our sun, become a neutron star? Explain your answer.



Please help me out.Can an average star become a neutron star?Basically it all depends on how the star will die.



Our Sun, and other stars like it, burn hydrogen at their cores through nuclear fusion. This process is powered by the Sun's gravity. The sun is so massive that the core reaches over 10 million degrees through sheer pressure. At that temperature, hydrogen nuclei can fuse into helium nuclei. This releases energy and keeps the pressure of gravity balanced with an internal force.



Once there gets to be enough helium at the sun's core, the balance is disrupted, and the Sun will expand into a red giant star. At that point, enough pressure will be created at the Sun's core to allow the helium to burn, and the sun will reach a new balance. But when helium fuses it turns into carbon, ad eventually there will be a lot of carbon that has built up at the Sun's core. This will cause another imbalance, but the Sun isn't big enough to create enough pressure for the carbon to burn. So instead the outer layers of the sun will blow off into what is called a planetary nebula, leaving a hot core of carbon remaining. This is called a white dwarf star, but since fusion isn't happening any more it is really a dead star, and it gradually loses heat until it doesn't shine any more.



But bigger stars have enough mass to get the carbon burning, and they go through a whole bunch of "stages" as one element creates another. The carbon turns to neon and oxygen, the neon turns to magnesium, the oxygen turns to sulfur and silicon, and in this way heavier and heavier elements are created. But once the star starts producing iron, the star is in trouble, because unlike other fusion reactions, which create energy, any fusion reaction involving iron causes the star to *lose* energy. The iron sucks the life out of the star, causing it to collapse, and then explode.



The core of such a star gets crushed to the point that all electrical charge is "squeezed" out, so that all that is left are neutrons (the part of atoms that don't have an electric charge). Basically the star becomes one gigantic atomic nucleus composed of neutrons, and that's what a neutron star is. It is completely solid.



If the star is even bigger, even the neutrons get crushed, and a black hole results.



So no, our sun won't become a neutron star; it's not massive enough.



By the way, the sun is not an "average star." It is actually well above average. In fact, the star is larger and brighter than over 90% of the stars in our galaxy. Most of the stars are smaller, dimmer, and redder than our Sun.



PeetCan an average star become a neutron star?
The sun will quietly die as a 0.51 solar mass white dwarf. For a neutron star it still needs as much as 0.44 solar masses. However, to produce a neutron star, you need to have a progenitor mass of 5 times more than the Chandrasekhar limit of 1.38 solar masses. There is one possible way, if a star can steal mass from a massive companion. However at only 1 solar mass, it needs more than 7 more solar masses to rob. That would mean to literally gobble mass from the companion since there is no such accretion rate possible. So the possible way breaks down and becomes impossible. I can think of another way. Let 2 low mass white dwarfs of less than 0.7 solar masses collide!



Clear skies!Can an average star become a neutron star?Neutron stars are basically leftovers of supernovas, or white dwarves growing in mass by a special scale called the Chandresekhar Limit. In most cases, it's from the leftovers of supernovas. But it's possible, however very likely. The sun, however, is not likely because it's too small to have a supernova--which is good for us.Can an average star become a neutron star?
No. Neutron stars are the remnants of very large stars that have supernova'd. Anything below 1.44 solar masses becomes a dwarf, anything above 5 solar masses becomes a black hole. Everything in between becomes a neutron star (or quark star, but it's not proven).Can an average star become a neutron star?Average is a dangerous word to use, it lacks definition. Our own Sun doesn't have enough mass to become a neutron star and it is far from 'average'. Most stars in the universe are cool, red dwarf stars that will quietly fade away as white dwarfs.

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