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  • Billions of years ago,

  • another planet smashed into Earth.

  • An event of this epicness

  • could have created our Moon.

  • It also could have brought

  • alien life to our planet.

  • Four and a half billion years ago,

  • Theia, a protoplanet the size of Mars,

  • struck our young Earth.

  • This collision scattered pieces

  • of both planets into space.

  • And many scientists argue

  • that these pieces

  • eventually coalesced into our Moon.

  • But what happened to the rest of Theia

  • is still a mystery.

  • The existence of blobs of material inside

  • Earth's mantle,

  • known as low sheer velocity provinces,

  • could be evidence

  • that parts of Theia fused with Earth.

  • These chunks are up to 1,000 km (621 mi)

  • in height and several times that in width.

  • They sit below Africa

  • and the Pacific Ocean,

  • straddling Earth's core

  • like a pair of headphones.

  • But other theories,

  • some dating back centuries,

  • suggest a completely different

  • explanation of what exists

  • under the surface.

  • A lush tropical paradise for aliens.

  • The Earth consists of four layers.

  • The crust, the mantle

  • and the outer and inner core.

  • But there hasn’t been any

  • successful exploration below the crust.

  • So there is much we don’t know

  • about the realities below the surface.

  • This has led to spectacular speculation,

  • like the Hollow Earth theory.

  • According to this theory,

  • our planet could be

  • a series of nested spheres,

  • centered around a central core.

  • In between these shells,

  • atmospheres could exist

  • that are capable of supporting life.

  • In the 17th century,

  • Edmond Halley,

  • the scientist who discovered

  • Halley's Comet, backed this theory.

  • Many others have added to it,

  • suggesting a small Sun

  • could be hanging

  • in the center of the Earth.

  • And plants, animals and humans

  • could be living there.

  • And not just humans,

  • but a race of superhumans.

  • Immortals who possess

  • sophisticated technology

  • to build hundreds of subterranean cities.

  • But if there were

  • aliens inside the Earth,

  • what would the conditions for life be?

  • Could the inside of our planet

  • be a luscious paradise?

  • Or a hot, hellish dump?

  • If you were to visit one

  • of the low-sheer velocity provinces,

  • you'd have to go 2,900 km (1,800 mi)

  • below the surface.

  • Here, you'd be surrounded

  • by magma, or liquid rock,

  • with temperatures

  • as high as 3,700 °C (6,692 °F).

  • And the weight of the crust

  • and mantle above you

  • would increase the pressure to over

  • 237,000 times

  • the atmospheric pressure,

  • you know, on the surface of the Earth.

  • Whatever life you find here

  • would need to exist

  • in these extreme conditions.

  • And these life forms would need

  • to evolve to extract oxygen

  • directly from the magma.

  • Or live without it.

  • They'd need to survive

  • without any sunlight.

  • Radiation would be

  • the primary energy source.

  • And lucky for them, the radioactive decay

  • of uranium, thorium and potassium

  • in the Earth's crust and mantle

  • already account for the primary source of heat

  • in the Earth's interior.

  • There could be all kinds of undiscovered

  • creatures down there.

  • But until you could

  • withstand the pressure

  • and heat to find out,

  • we'll never know.

  • And as for the Hollow Earth,

  • it's nice to imagine

  • a paradise world underneath our feet

  • instead of layers

  • upon layers of hot molten rock.

  • And who knows, maybe there is alien

  • life down there.

  • Just like all those underwater aliens

  • hiding in the world's deepest lake.

  • Oh, wait.

  • That's a story for another WHAT IF.

Billions of years ago,

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What If Aliens are Living Inside Earth?

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    たらこ posted on 2022/03/10
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