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We Asked a NASA Scientist: Where Did Our Moon Come From?

Artist’s impression of the Moon-forming event. Numerous moon formation theories have been suggested by researchers. Nonetheless, the most widely-accepted explanation, backed by the available evidence, posits that the moon resulted from a massive collision between the proto-Earth and another protoplanet approximately the size of Mars, often referred to as “Theia.” Credit: NASA/JPL-CalTech/T. Pyle

Where did our Moon come from?

Well, actually, there have been several theories over many decades. Earlier versions of lunar formation theories included capture, where the Moon would have been a strayed planetoid. Another version was fission, where the Earth was spinning so fast that it would have ejected out of the Earth and then formed its own body.

This led to our current theory, the giant impactor theory. So this collision was during the late stages of planetary formation throughout our entire solar system, when planets were still very new and very much forming. So this happened when Earth was just an embryo — a baby planet, and this was actually in a crash course collision with Theia, which is a MarsMars is the second smallest planet in our solar system and the fourth planet from the sun. It is a dusty, cold, desert world with a very thin atmosphere. Iron oxide is prevalent in Mars' surface resulting in its reddish color and its nickname "The Red Planet." Mars' name comes from the Roman god of war.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]”>Mars-size planetoid. And this collision ripped apart early Earth’s crust. And that crust then coalesced. It snowballed into a wholly separate entity, which we now call the Moon.

So where did our Moon come from? Well, currently, our understanding is that the Earth had collided with a Mars-sized object named Theia. But once we send future astronauts to the lunar surface again, who knows? We may actually have a whole new theory in the coming decades.

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Where did our Moon come from? Over the years, there have been several theories, but most scientists think it’s likely that a Mars-sized object smashed into Earth, creating what we now see in the sky. NASAEstablished in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. Its vision is "To discover and expand knowledge for the benefit of humanity." Its core values are "safety, integrity, teamwork, excellence, and inclusion." NASA conducts research, develops technology and launches missions to explore and study Earth, the solar system, and the universe beyond. It also works to advance the state of knowledge in a wide range of scientific fields, including Earth and space science, planetary science, astrophysics, and heliophysics, and it collaborates with private companies and international partners to achieve its goals.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]”>NASA scientist Caitlin Ahrens shines a light on the Moon’s mysterious origins. Credit: NASA

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Source: SciTechDaily