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The Planet Earth
Have you ever imagined what Earth looked like in the beginning? It was once
different than it is now. Our Earth didn't exist yet in 4.6 billion years ago. There
was only a newly formed proto sun, and a ring of gas and dust. Our planet was
formed in 4.54 billion years ago. Back then, it was about as far inhabitable as
possible. The conditions of Earth were really hellish. There were no landscapes
yet, but a sea of fire in molten rock. The surface temperature reached 4700
degrees Celsius. Some time later, the temperature of the Earth slowly decreased.
There was still no oxygen during this time, so no life can survive yet.
About 650 million years ago, according to a popular theory, our planet was a
snowball. Scientists assumed that the planet was completely covered with ice. The
equator was even as cold as the modern Antarctica. Even so, no ice age can kill
volcanoes. The eruptions melted the glaciers. About 450 million years ago, plants
and arthropods began to actively conquer the land, and around 419 million years
ago, the first insects appeared.
