A picture of the Earth taken by the Apollo 17 Lunar Mission

The Earth formed around 4.54 billion years ago by asteroids colliding together, which also created what we know today as the Sun. The energy created by these collisions was stored as heat in the centre of the Earth. But the first life forms didn't appear until 3.8 billion years ago. These life forms are graphite found in metasedimentary rocks, discovered in Western Greenland. 1 billion years ago the Earth cooled, and volcanic eruptions are less common. Water then started to settle, forming oceans. Green algae then started to form in the water, which photosynthesises and produces oxygen, which is put into the air. The oxygen then formed a layer of ozone around the Earth, which protects it from poisonous ultraviolet rays from the Sun. And then land started to drift apart, forming Pangaea.


A map of Pangaea but with modern countries

Pangaea was a supercontinent that existed during the late Paleozoic and early Mesozoic eras. It formed approximately 300 million years ago and then began to break apart after about 100 million years. Unlike the present Earth, much of the land mass was in the southern hemisphere. Pangaea was the first reconstructed supercontinent and it was surrounded by a super ocean, known as Panthalassa. Pangaea was made up of what we know today as the 7 continents; Europe, Asia, North America, South America, Australia, Africa and Antartica. The reason for the continents splitting up is because of tectonic plates moving underneath Pangaea, causing earthquakes that split apart Pangaea.


All of the major tectonic plates

Plate tectonics is the theory that Earth's outer shell is divided into several plates that glide over the mantle, the rocky inner layer above the core. The plates act like a hard and rigid shell compared to Earth's mantle. This strong outer layer is called the lithosphere. The driving force behind plate tectonics is convection in the mantle. Hot material near the Earth's core rises, and colder mantle rock sinks. The convection drive plates tectonics through a combination of pushing and spreading apart at mid-ocean ridges and pulling and sinking downward at subduction zones, researchers think. Scientists continue to study and debate the mechanisms that move the plates.


There is a possibilty that the continents will re-join, forming a second supercontinent. The name for this is Pangaea Ultima, and could happen in the next 250 million years. It would look completely different to Pangaea, as the tectonic plates are still moving away from each other, but because the Earth is a sphere, they will eventually join together again. At 250 million years in the future, the Atlantic and Indian oceans are predicted to have closed. North America is predicted to have already collided with Africa, but be in a more southerly position than where it drifted. South America is predicted to be wrapped around the southern tip of Africa, with Patagonia in contact with Indonesia, enclosing a remnant of the Indian Ocean (called the Indo-Atlantic Ocean). Antarctica would then once again be at the South Pole and the Pacific will have grown wider, encircling half the Earth.

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