How was the Earth formed? About one hundred billion years ago the Earth, the Sun, and

all the planets of the Solar System were nothing but a cloud of cold dust particles swirling through empty space. Gradually, these particles were attracted to each other and came together to form a huge spinning disk.

By Luis Andrés Manchado

As it spun, the disk separated into rings and the motion

made the particles white-hot. The center of the disk became

the sun, and the particles in the outer rings turned into

large balls of gas and molten-liquid that cooled and

condensed to take on solid form. Four or five billion years

ago, they turned into the planets that we know today as

Earth, Mars, Venus, and the outer planets.

Giant impact theory The Giant Impact Theory says that Earth’s moon was created in an apocalyptic

collision between a planetary body the size of Mars called Theia and the early Earth. According to the theory, the planet smashed up against Earth, releasing so much energy that it melted and vaporized Theia and much of the proto-Earth’s mantle. The Moon then condensed out of the cloud of rock vapor, some of which also re-accreted to the Earth.

Without the moon, planetary scientists believe the Earth would spin more rapidly, making days shorter, weather more violent, and climate more chaotic, which they believe would have also resulted in humans not coming to existence.

The Earth became a planet with a hard crust about 4000 million years ago. Even though it was a much cooler place by then, it was still too hot to support any forms of life. The Earth did not have any water or air. Earthquakes, volcanic eruptions and meteorites were common events at that time. The eruption of volcanoes created our actual atmosphere and oceans (the atmosphere has prevented most of the meteorites to hit Earth ever since). Meteors also hit the Moon, that’s why we can see large craters when we look at it.