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The Origin of the Ocean - Stars from Seas - Stars make Heavy Elements form Lighter Ones

6 important questions on The Origin of the Ocean - Stars from Seas - Stars make Heavy Elements form Lighter Ones

What is the 'condensation theory'?

A theory based on this interference explains how stars and planets are believed to form.

How does the life of a star begin?

A diffuse area of a spinning nebula begins to shrink and heat up under the influence of its own weak gravity. The sphere flattens and condenses at the center in a knot of gasses (now called a 'protostar'). This huge star is contracted and the internal temperature is raised. Then, hydrogen atoms begin to fuse to form helium.

How does a star arise from a protostar?

When nuclear fusion begins at a temperature of about 10 million degrees Celcius, a lot of energy is released, which marks the protostar to be a star when shrinking is stopped. The star is now stable, neither expanding or shrinking.

When is a star called a 'red giant'?

The life of a star depends on its initial mass. When a medium-mass star (like our sun) begins to consume carbon and oxygen atoms, its body swells due to increased energy output. The dying giant throws off gas and heavier elements. But most of the carbon and oxygen stays trapped inside the star's heart.

What about the lives of stars heavier than our sun?

These lives are a lot shorter, as the fusion of elements happens at a much faster rate as they are larger and hotter. They can now make elements up to the mass of iron. The star dies when the center collapses and when the material can no longer be kept together, a super nova happens.

What is a 'super-nova'?

The energy of the inward falling material is converted into a cataclysmic explosion of about 30 seconds. The energy released by the gas layers falling towards the center, produces a shock wave, which 'blows' the outer layers of the star. This happens very suddenly and sprays all sorts of elements (including gold, mercury and uranium) into space.

The question on the page originate from the summary of the following study material:

Oceanography: An Invitation to Marine Science | 9781305480575 | Tom S Garrison

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