The Origin of the Universe

All the stars in the universe started off as a dense cloud of gas called a nebula. Amongst these gases a protostar is born. Compared to other stars, a protostar is a smaller and colder star. Depending on how large the protostar is will determine whether the star grows into a large star or a small star. Both stars will then grow into either a red giant or a super red giant. The next stage in star development is when a red giant can no longer support its self just by nuclear fusion and the core heats up. As the core heats up it forces the outer part of the star to blow away. The hot core makes the outer region of the star (the part which has been blown away) glow. This is now called a planetary nebula. The hot core continues to heat up until it becomes a white dwarf. It shrinks to about the size of the earth. It is extremely dense as the white dwarf's mass does not change. Though when a red super giant cannot support itself, it explodes into the form of a supernova. The remnants can sometimes form a protostar or a black hole.

A red giant is a large, old, luminous star. It has a relatively low surface temperature and a diameter considerably larger than the sun.The Red Giants produce a large amount of light because of their great size The Red Giant is usually 10-1500 times the size of our sun’s current size.When the hydrogen atoms in a star fuse together, the amount of hydrogen begins to reduce as the amount of helium increases. As the hydrogen burns inside the red giant, the amount of energy produced decreases over time.A super red giant is formed from a large star. All stars are expected to pass through the red giant phase at some time in their lifetime.Most red giants are actually red but some vary in colour from red, orange or even yellow. This is due to the different chemicals inside it.As the outer shell of a super red giant expands, the core shrinks and heats up. When the temperature gets too high the helium atoms come together to create carbon. The core is now stabilised. Then at the end of a red giant’s life, it explodes in the form of a supernova.