LIFE CYCLE OF A STAR

EARLY LIFE

• This clumping is often caused by energy waves from nearby exploding supernovae.
• As they collapse, the molecules that form the clouds compress in upon each other to form helium and hydrogen.
• Once gravity pushes them together strongly enough, nuclear fission will begin to occur in the core of the star.
• This process will continue throughout the life of the star, until all of the fuel is used up.

STAGE 2

• A region of condensing matter will begin to heat up and start to glow forming Protostars
• If a protostar contains enough matter the central temperature reaches 15 million degrees centigrade.

STAGE 3

• At this temperature, nuclear reactions in which hydrogen fuses to form helium can start.
• The star begins to release energy, stopping it from contracting even more and causes it to shine. It is now a Main Sequence Star.

FINAL STAGE

• Eventually the Main Sequence star burns through the hydrogen in its core ending its life cycle. Some stars become white dwarfs after their cycle is over.

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