What prevents a star from collapsing under its own gravitational attraction?

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Stars resist collapsing under their own gravitational attraction due to several counteracting forces. In the sun, nuclear fusion generates heat and radiation pressure that maintain equilibrium against gravity. White dwarfs rely on electron degeneracy pressure, a quantum effect that prevents electrons from occupying the same space. Neutron stars experience a similar phenomenon known as neutron degeneracy pressure. These mechanisms are crucial for the stability of stars throughout their life cycles.
nlink1979
According to Newton's Law of Gravitation, all objects with mass attract one another. This law implies that all of the atoms that make up a star, such as our sun, are gravitationally attracted to one another. How is a star able to resist collapsing under its own gravitational attraction?

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Nicole
 
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There are numerous interactions that counteract gravity, preventing such a collapse. In our sun, the process of nuclear fusion creates large amounts of heat and radiation; this radiation pressure keeps the star in equilibrium. In stars like white dwarfs, something called electron degeneracy pressure keeps the star from collapsing. This is a quantum effect that restricts the number of electrons we can squish into a certain volume, and acts to keep them apart. In neutron stars, a similar pressure arises from neutron degeneracy.
 
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