Billions of years ago, our planet, Earth, collided with another planet-like object. Scientists have nicknamed it "Theia". This event is what was believed to have changed our Earth into a molten ball of rock. However, geochemist Sujoy Mukhopadhyay and his team have discovered, through isotopes recovered from deep inside the Earth's mantle, that some of the Earth material has survived to this day,
Though the energy released from the impact of Theia was great, they believe that it was not evenly distributed throughout the Earth. This means a big part of the hemisphere that was hit would be completely vaporized, but the opposite side would be somewhat shielded. This would make it possible for the ancient Earth to have survived all these years.
I think it's amazing that it's been millions and billions of years and yet we can still trace the chemical history of our planet today. The fact that these traces are even still here to be analyzed is incredible. When you compare this amount of time to an average human lifespan, it makes our lives seem so small.
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