Formation and evolution of the Solar System  From Wikipedia, the
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navigation, search Artist's conception of a protoplanetary disk
The formation of the Solar System is estimated to have begun
4.6 billion years ago with the gravitational collapse of a small
part of a giant molecular cloud.[1] Most of the collapsing mass
collected in the centre, forming the Sun, while the rest
flattened into a protoplanetary disk out of which the planets,
moons, asteroids, and other small Solar System bodies formed.
Pre-solar nebula[edit]      At this point in its evolution, the
Sun is thought to have been a T Tauri star.[22] Studies of T
Tauri stars show that they are often accompanied by discs of
pre-planetary matter with masses of 0.001–0.1 solar masses.[23]
These discs extend to several hundred AU—the Hubble Space
Telescope has observed protoplanetary discs of up to 1000 AU in
diameter in star-forming regions such as the Orion
Nebula[24]—and are rather coo