Comet impacts formed continents when Solar System entered arms of Milky Way
The conventional wisdom regarding the genesis of our planet has been turned on its head by new study from Curtin University that suggests the early continents of Earth were formed as a result of comet impacts as our Solar System entered and exited the spiral arms of the Milky Way Galaxy. A new perspective on Earth's early history and our place in the universe is provided by the new research, which was published in Geology and challenges the conventional wisdom that the planet's crust was only created by internal processes. Studying minerals in the Earth's crust revealed a rhythm of crust production every 200 million years or so, Professor Chris Kirkland, the study's principal investigator, from Curtin's School of Earth and Planetary Sciences, said. This rhythm matched our Solar System's transit through regions of the galaxy with a higher density of stars. Every 200 million years or so, the Solar System passes between the spiral arms of the Milky Way as it revolv...