This is an image of the solar system.
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The Beginning of the Solar System
Scientists believe that the solar system was formed when a
cloud of gas and dust in space was disturbed, maybe by the expl
osion of a nearby star (called a
This explosion made waves in space which squeezed the cloud of gas and dust.
Squeezing made the cloud start to collapse, as gravity pulled
the gas and dust together.
Just like a dancer that spins faster as she pulls in her arms, the cloud began to spin as it collapsed. Eventually, the cloud grew hotter and denser in the center, with a disk of gas and dust surrounding it that was hot in the center but cool at the edges.
As the disk got thinner and thinner, particles began to stick together and form clumps. Some clumps got bigger, as particles and small clumps stuck to them, eventually forming planets or moons .
Near the center of the cloud, where planets like Earth formed, only rocky material could stand the great heat. Icy matter settled in the outer regions of the disk, where the giant planets like
As the cloud continued to fall in, the center eventually got so hot that it became a star, the Sun, and blew most of the gas and dust of the new solar system. By studying fragments of rock left over from this early phase of the solar system, scientists have found that the solar system is about 4600 million years old!
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