When a white dwarf exceeds the Chandrasekhar limit, it can no longer support itself against its own gravity and undergoes a catastrophic collapse, resulting in a Type Ia supernova. Here's a breakdown of what happens:

The Chandrasekhar Limit

* This limit represents the maximum mass a white dwarf can have while remaining stable. It's approximately 1.44 solar masses.

* This limit arises from the balance between the outward pressure generated by degenerate electron gas within the white dwarf and the inward pull of gravity.

Exceeding the Limit

* If a white dwarf accretes enough mass from a companion star (either a normal star or another white dwarf) to exceed the Chandrasekhar limit, the degenerate electron pressure can no longer support the star's weight.

* This causes a runaway nuclear fusion reaction in the core of the white dwarf.

The Supernova Explosion

* The core of the white dwarf suddenly ignites, fusing carbon and oxygen into heavier elements in a rapid and violent process.

* This process releases an immense amount of energy, causing the white dwarf to explode as a Type Ia supernova.

* The explosion is so powerful that it can outshine entire galaxies for a short period.

* The explosion completely disrupts the white dwarf, leaving behind no remnant.

Consequences of the Supernova

* The supernova explosion creates a shock wave that can trigger star formation in nearby regions.

* The heavy elements synthesized during the explosion are scattered throughout the universe, contributing to the chemical enrichment of interstellar gas clouds.

* These supernovae play a crucial role in the evolution of galaxies and the distribution of elements in the universe.

Key Points:

* Type Ia supernovae are important tools for astronomers to study distances in the universe.

* The brightness of Type Ia supernovae is relatively consistent, allowing them to be used as "standard candles" to measure distances.

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