This drawing shows how forming planets drew gas to themselves.
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Image from: The New Solar System
As shown in this picture, while they were forming in the flattened disc of the solar nebula, the nucleii of the planets-to-be (called proto-planets) drew material to themselves from the cloud of gas and dust around them. The bigger protoplanets were able to attract even more gaseous material unto themselves.
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Shop Windows to the Universe Science Store!
Learn about Earth and space science, and have fun while doing it! The games
section of our online store
includes a climate change card game
and the Traveling Nitrogen game