UNIVERSE
PLANETARY FORMATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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4.6 million years ago.
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14.6 million years ago.
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4.6 billion years ago.
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14.6 billion years ago.
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Detailed explanation-1: -The Sun and the planets formed together, 4.6 billion years ago, from a cloud of gas and dust called the solar nebula. A shock wave from a nearby supernova explosion probably initiated the collapse of the solar nebula. The Sun formed in the center, and the planets formed in a thin disk orbiting around it.
Detailed explanation-2: -Formation. When the solar system settled into its current layout about 4.5 billion years ago, Earth formed when gravity pulled swirling gas and dust in to become the third planet from the Sun. Like its fellow terrestrial planets, Earth has a central core, a rocky mantle, and a solid crust.
Detailed explanation-3: -The time frame of the Solar System’s formation has been determined using radiometric dating. Scientists estimate that the Solar System is 4.6 billion years old. The oldest known mineral grains on Earth are approximately 4.4 billion years old.
Detailed explanation-4: -4.5 billion years ago: Mercury, Venus, Earth, and Mars form.