Parts of which ancient planet might be buried inside Earth?
Scientists believe that a really long time ago, a big asteroid, as big as Mars, hit the developing Earth. This crash helped make the Moon. The impact may have left huge remains of the asteroid near the Earth's core.
Scientists also think that Earth was created about 4.5 billion years ago, and not long after that, the Moon formed. They say it happened when two developing planets, one being Earth and the other a Mars-sized rock called Theia, smashed into each other. A new study suggests that some parts of Theia got stuck under Earth's mantle.
Who conducted the study?
A scientist named Qian Yuan and a group of researchers did the study. It was published in the Nature journal. In their study, they found that some of Theia’s material may form two big portions of Earth's mantle today.
Inside Earth, there are layers. There’s the core. Above it is the mantle, and on top is the Earth's outside layer, the crust. Scientists study what's inside our planet for many reasons. They found two heavy masses in the lower mantle near the core’s boundary.
One is under South Africa, and the other is under the Pacific Ocean. They're different from the other materials around them and might have been there for a very long time. Scientists don't know exactly how they got there, but the new study suggests they might have come from Theia.
How did the scientists conduct the study?
The scientists used a simulation to show that a part of Theia's mantle could have transferred into Earth's lower mantle. They also studied how Earth's insides changed over time to find out where we might see clues from Theia and how they might have changed.
The simulations showed that the collision might have created those big chunks and the Moon. Some of Theia's material might have mixed with Earth, while other pieces formed the Moon.
