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Stars
form in nebulae, which are clouds of gas (mostly hydrogen) and dust. A
nebula can also be called a stellar nursery. There are many stellar
nurseries in galaxies.
Stars begin as clouds of gas and dust, composed of 97% of hydrogen and
3% of helium. They collect more as they grow. When enough gas and dust
is collected into a giant ball, the temperature inside it reaches 15
million degrees. It becomes a giant ball because the gas and dust
collapse under its own gravity and weight. At this point, nuclear
fusion begins to occur and the ball of gas and dust start to glow. A
new star is born.
As the
formation of the gas and dust progresses and the temperature reaches 15
million degrees, the pressure at the center becomes great. As the
contraction continues, the nuclei in the plasma move faster. The nuclei
crash into each other so hard that they fuse together or attach.
Electromagnetic Radiation forms when energy reaches the outer layers of
the ball of gas and dust, and moves into space. The ball, which is now
a star, starts to glow. That is how stars are born.
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