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the early system

The hypothesis for the formation of the Solar System starts before the Sun formed. The material that now makes up the Sun was distributed thinly in interstellar space in the form of a large cloud of gas and dust. In astronomical terminology, dust is made of tiny solid particles about 10-4 to 10-5 millimeters across. The Sun began to form a little more than 4.6 billion years ago when this cloud (or part of it) began a process of contraction and flattening. which the planets, moons, asteroids, and other small Solar System bodies formed or more supernovae occurred nearby. A shock wave from a supernova may have triggered the formation of the Sun by creating relatively dense regions within the cloud, causing these little ones to form.