Around 1.5 million years after the big bang the clumps of hydrogen and helium that had just been made broke up to make huge galaxy-sized clouds. In the dark wells of the universe matter fell together. Some places were denser than others and after almost 30 million years clumps of gas and dust fell in on each other, crushing under their own weight. As these giant gas clouds spun they became denser and denser causing objects to collide more and more warming up everything around them.

Most of these balls of gas remained unchanged, making brown dwarfs, which are about the size of Jupiter, the heavier ones pushed at the hydrogen atoms in their centre so much that they eventually ignited. The atoms deep inside fell into their constituent parts again, but higher up more and more protons were pushed onto the neutrons making new elements. Alchemy began in the stars as hydrogen atoms fused together to make more helium. As with all cases of nuclear fusion huge amounts of energy is released exploding in a fire strong enough to keep the star burning for millions more years. After all of the hydrogen is used up stars can then burn helium to create heavier elements, this releases less energy as less mass is lost. The stars then loose some of their thermal pressure and they collapse a little. This can ignite them again and give them enough energy to keep burning, making heavier atoms and causing the star to swell, shedding its skin in a giant red cloud. These are known as red giants. Some stars stop here, leaving a core as small as the Earth made of heavily compressed carbon, the same thing as diamonds, and weighing as much as the Sun. This is known as a white dwarf.

The more massive a star is the hotter, and bluer, it is. The cooler a star gets the redder it becomes, going down the rainbow through green, yellow and orange. Hotter stars can burn more elements it can burn into existence but live significantly shorter lives. All of the natural elements burn into existence inside the most massive stars. Lastly, they grow a skin of iron which sets off a nuclear fission reaction resulting in a supernova. The star explodes with the power of a trillion nuclear bombs, splashing the natural elements all around them. Sometimes after these explosions the core is so heavy that all of the electrons are released from their atoms creating an electronic sea. In heavier stars still the electrons and protons melt together creating neutrons once again. These are known as neutron stars.

The largest stars leave ashes so heavy that they fall in on each other, stretching space into a black hole. Black holes are wells in spacetime so deep that even light cannot escape. Black holes can be as massive as 250 million Suns, these are so heavy that they bent space all around the newly formed galaxy, they pulled at the stars out of reach just enough to ignite the sky around them. Some produce screaming bursts of light away from its edges becoming a quasar.

Over 8 billion years ago one of these supernova explosions created a cloud of dust and gas so heavy that almost all of this fell back together again, and after another 3 billion years it began to glow as a dull yellow star. A tiny amount of matter was left swirling around the valley of space created by the weight of what was to be called the Sun, some parts were denser than others and so they fell together making larger and larger clumps. After a few tens of thousands of years the planets took their shape. Our Earth is just part of the debris of a huge stellar explosion, and from these ashes humans grew.

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