Earth, also called the world and, less frequently, Gaia is the third planet from the Sun, the densest planet in the Solar System, the largest of the Solar System’s four terrestrial planets, and the only astronomical object known to accommodate life.
Fast Facts about Earth
1. One day on Earth takes 24 hours (this is the time it takes the Earth to rotate or spin once). Earth makes a complete orbit around the sun (a year in Earth time) in about 365 days.
2. Of all the planets in our solar system, the Earth has the greatest density. This varies according to the part of the planet; for example, the metallic core is denser than the crust. The average density of the Earth is approximately 5.52 grams per cubic centimetre.
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3. Earth is a rocky planet, also known as a terrestrial planet, with a solid and dynamic surface of mountains, valleys, canyons, plains and so much more. What makes Earth different from the other terrestrial planets is that it is also an ocean planet: 70 percent of the Earth’s surface is covered in oceans.
4. The Earth’s atmosphere is made up of 78 percent nitrogen (N2), 21 percent oxygen (O2) and 1 percent other ingredients — the perfect balance for us to breathe and live. Many planets have atmospheres, but only Earth’s is breathable.
5. Earth has one moon. Another name for a moon is satellite.
6. Earth is the only planet not named after a god. The other seven planets in our solar system are all named after Roman gods or goddesses. Although only Mercury, Venus, Mars, Jupiter and Saturn were named during ancient times, because they were visible to the naked eye, the Roman method of naming planets was retained after the discovery of Uranus and Neptune.
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7. Earth is the perfect place for life.
8. Earth’s atmosphere protects us from incoming meteoroids, most of which break up in our atmosphere before they can strike the surface as meteorites.
9. The Earth was once believed to be the centre of the universe. Due to the apparent movements of the Sun and planets in relation to their viewpoint, ancient scientists insisted that the Earth remained static, whilst other celestial bodies travelled in circular orbits around it. Eventually, the view that the Sun was at the centre of the universe was postulated by Copernicus, though this is also not the case.
10. The name ‘Earth’ is derived from the Old English word “ertha” and the Anglo-Saxon word “erda” which means ground or soil.
References: Space Facts Wikipedia
