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Name: Guy
Status: other
Grade: other
Location: NV
Country: N/A
Date: N/A


Question:
Hello! I watched a documentary recently and they mentioned that the sun is decreasing by 5 feet daily, and has been for as long as we have had the knowledge to study the sun. Is this true? Is it really decreasing by 5 feet DAILY and has been for all of its existence (or for as long as we have been able to study it)?


Replies:
Guy,

The Sun is so bright because fusion is occurring in its center. Fusion is the process where two forms of a hydrogen atom (the smallest atom) combine to make a helium atom (the next smallest atom). It would take a very long explanation to describe everything that is going on, but basically, when fusion occurs and you generate a lot of helium at the center of the Sun, the core shrinks. This shrinkage eventually gets to the surface. There will also come a point where the hydrogen in the Sun will run out and fusion stops for a second (or probably much less). When this occurs, the Sun will collapse under its own weight until enough pressure is put on the new Helium core to force the Helium to start the fusion process. When this happens, the collapse will send a shock wave out through the Sun and the Sun will expand just past where the Earth is now! That will be a warm day indeed.

Matt Voss



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