Question

How to make Magazine on Life cycle of a Star?

Answer 1

The Life Cycles of Stars
I. Star Birth and Life
Imagine an enormous cloud of gas and dust many light-years across. Gravity, as it always
does, tries to pull the materials together. A few grains of dust collect a few more, then a few
more, then more still. Eventually, enough gas and dust has been collected into a giant ball
that, at the center of the ball, the temperature (from all the gas and dust bumping into each
other under the great pressure of the surrounding material) reaches 15 million degrees or so.
A wondrous event occurs.... nuclear fusion begins and the ball of gas and dust starts to glow.
A new star has begun its life in our Universe.
So what is this magical thing called “nuclear fusion” and why does it start happening inside
the ball of gas and dust? It happens like this..... As the contraction of the gas and dust
progresses and the temperature reaches 15 million degrees or so, the pressure at the center of
the ball becomes enormous. The electrons are stripped off of their parent atoms, creating a
plasma. The contraction continues and the nuclei in the plasma start moving faster and faster.
Eventually, they approach each other so fast that they overcome the electrical repulsion that
exists between their protons. The nuclei crash into each other so hard that they stick together,
or fuse. In doing so, they give off a great deal of energy. This energy from fusion pours out
from the core, setting up an outward pressure in the gas around it that balances the inward
pull of gravity. When the released energy reaches the outer layers of the ball of gas and dust,
it moves off into space in the form of electromagnetic radiation. The ball, now a star, begins
to shine.
New stars come in a variety of sizes and colors. They range from blue to red, from less than
half the size of our Sun to over 20 times the Sun’s size. It all depends on how much gas and
dust is collected during the star’s formation. The color of the star depends on the surface
temperature of the star. And its temperature depends, again, on how much gas and dust were
accumulated during formation. The more mass a star starts out with, the brighter and hotter it
will be. For a star, everything depends on its mass.
Throughout their lives, stars fight the inward pull of the force of gravity. It is only the
outward pressure created by the nuclear reactions pushing away from the star's core that
keeps the star “intact”. But these nuclear reactions require fuel, in particular hydrogen.
Eventually the supply of hydrogen runs out and the star begins its demise.