How was the sun formed?
(Lansing State Journal, October 11, 1995)

Our sun began it's life as a rotating cloud of interstellar dust and gas.  Associated with all matter is the force of gravity, and this stellar nursery was no exception.  Matter began a gravitational collapse.

Because of the rotation, the cloud flattened and much of the matter became concentrated at its center.  Gravity fundamentally depends upon mass and distance; the more massive an object, the stronger the attractive force it exerts on other objects.

At the center, strong gravitational forces confined particles to a relatively small space.  As a result, temperatures increased.

Over time, enough matter collapsed upon the center that it was heated to the point where nuclear reactions could begin.  A star was born.

Nuclear reactions within the core of a star release enormous amounts of energy and create an outward pressure that prevents further collapse.

It is this balance between pressure and gravity that keeps a star like our sun stable.

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