giant impact theory

1. A theory that explains the origins of Earth's moon, postulating that an asteroid roughly the size of Mars impacted the Earth during its formation. This impact resulted in rocky surface material being blown outward from the Earth, some of which accreted to form the Moon. This theory explains the similar oxygen isotope ratios between the Earth and the Moon as well as the Moon's lack of an iron core. It also accounts for the angular momentum that was necessary for the Moon to reach its current position.

Example Sentences

And this is kind of where the Giant Impact Theory comes along, supported, as you say, entirely on the back of theory.

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Giant Impact Theory is really you know a story of science following what the computers tell us.

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What’s more, not only is the chemistry of the giant impact theory flawed, but also so is the physics.

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One stumbling block of the giant impact theory of moon formation has been the incredible isotopic similarities between the Earth and the moon.

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Astrochemist Richard Starr of NASA's Goddard Space Flight Center in Greenbelt, Maryland, and physicist Patrick Peplowski of the Johns Hopkins University's Applied Physics Laboratory in Laurel, Maryland, both gave talks at the conference yesterday announcing the death of the giant impact theory for Mercury.

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