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→Formation of the Planets
: After a [[nebula]] has collapsed to form a [[protostar]] the [[protostar]] is surrounded by a disk of [[gas]] and dust.
: [[Gravity]] causes the [[gas]] and dust clumps together to form grains, which then come to together to form [[asteroid]]s.
: Over millions of [[year]]s the [[asteroid]]s collide to form bigger and bigger [[asteroid]]s until they are so large that they have enough [[gravity]] to pull their [[matter]] in to a [[sphere|spherical]] shapeand become [[Dwarf Planet|dwarf planets]].: Eventually the [[Dwarf Planet|dwarf planets]] may sweep enough [[material]] out of their [[orbit]]al path that they are considered [[planet]]s.
===Examples===