Life cycle of a star
Created | Updated Dec 5, 2002
Birth
Imagine, if you will, a vast cloud of deuterium*, many light years across. now, something happens which causes a ripple, in turn causing the deuterium to collapse in on itself, forming vast spheres called globules. These in turn collapse even further, and the globule becomes a protostar. The protostar emits infra-red and red light waves. Some parts of the globule may break off and form planets, moons, and asteroids. As the protostar cotracts nuclear fusion takes place, as the deuterium is convereted to helium. The protostar emits increasingly shorter wanelengths, until it becomes a true star.
Life
The star is divided into layers like a planet. From the centre outwards, they are: core, mantle, and corona. Within these, the deuterium ions move so fast that the kinetic energy overrides the charges, and forces the nuclei together to form helium. This releases a positron, which then collides with a wandering electron, releasing vast amounts of heat and nutrinos.
Death
White Dwarf
The star simply expends all it's energy and frizzles down to a tiny (for a star) white dwarf. This may exist for centuries bofore finally dying altogether.
Supernova
Energy increases, causing the star to expand. If this happens to ours, it will engulf mercury alogether and burn off all life left no Earth (and maybe Mars, if we've gotten that far). It's gravity will cause it to collapse again, but then energy will increase and it eill go through this cycle again, until it finally explodes.
Neutron Stars, Pulsars, an Black Holes
When it shrinks back, the protons and electons may be forced together to form neutrons. This neutron star may emit radio waves; those that do so are called pulsars. However, the neutron star may even continue to collapse until it reaches critical density and forms a black hole (more on this elsewhere in the guide).
