Currently Accepted Hypotheses
The most widely accepted theory of planetary formation, known as the nebular hypothesis, maintains that 4.6 billion years ago, the Solar System formed from the gravitational collapse of a giant molecular cloud which was light years across. Several stars, including the Sun, formed within the collapsing cloud. The gas that formed the Solar System was slightly more massive than the Sun itself. Most of the mass collected in the centre, forming the Sun; the rest of the mass flattened into a protoplanetary disc, out of which the planets and other bodies in the Solar System formed.
Just as the Sun and planets were born, so they will eventually die. As the Sun begins to age, it will cool and bloat outward to many times its current diameter, becoming a red giant, before casting off its outer layers (forming what is misleadingly called a planetary nebula) and becoming a stellar corpse known as a white dwarf. The planets will follow the Sun's course; some will be destroyed, others will be ejected into interstellar space, but ultimately, given enough time, the Sun's retinue will disappear.
Read more about this topic: History Of Solar System Formation And Evolution Hypotheses
Famous quotes containing the words accepted and/or hypotheses:
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