Solar nebula

In cosmogony, the nebular hypothesis is the currently accepted argument about how Earth's Solar System formed. It was first proposed in 1734 by Emanuel Swedenborg. In 1755 Immanuel Kant, who was familiar with Swedenborg's work, developed the theory further. He argued that nebulae slowly rotate, gradually collapsing and flattening due to gravity and eventually forming stars and planets, in a process of planetary formation. A similar model was proposed in 1796 by Pierre-Simon Laplace. These can be considered early theories of cosmology.
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The solar system formed from a cloud of material known as the solar nebula. The trigger for the collapse of the solar nebula into the solar system is thought to have been the explosion of a nearby supernova just over 4.6 billion years ago. The material remaining after formation dissipated when the Sun passed through the T Tauri phase.