THE EARTH

 “Look deep into nature, and then you will understand everything better.” -- Albert Einstein

Mass: 5,972,190,000,000,000 billion kg

Equatorial Diameter: 12,756 km

Polar Diameter: 12,714 km

Equatorial Circumference: 40,030 km

Known Moons: 1

Notable Moons: The Moon

Orbit Distance: 149,598,262 km (1 AU)

Orbit Period: 365.26 Earth days

Surface Temperature: -88 to 58°C

Earth is the third planet from the Sun and the largest of the four Inner Planets. According to evidence from radiometric dating and other sources, Earth was formed about 4.54 billion years ago. Earth gravitationally interacts with other objects in space, especially the Sun and the Moon.  It is the planet that you live on and is special because it is the only place in the whole Solar System known to support life. It is in the perfect position in the Solar System - not too close to the Sun and not too far away - meaning that it has the right climate for life to exist - not too hot nor too cold. It also has plenty of water, a key ingredient for all living things. In fact most of the Earth's surface (70% of it) is covered by water. Surrounding the planet is a layer of atmosphere which prevents most of the Sun's poisonous rays from reaching the surface. This atmosphere also contains oxygen which many animals (including people!) need to be able to breathe. 

Earth is a planet which orbits the Sun every 365 and a quarter days, taking 23 hours and 56 minutes to turn on its axis. This is the reason that a year is 365 days long and a day is 24 hours long. It has one Moon which orbits the planet every 27 days. It is a geologically active planet, meaning that its surface features and landscapes are constantly being reformed by volcanoes, earthquakes, changes in climate (temperature), and weather. Like other planets and moons, it is a target for asteroids and meteorites travelling through space. Most of these objects burn up in the planet's protective atmosphere, although some do survive and leave huge impact craters. For thousands of years, people believed that Earth was at the center of the universe and that everything else - the Sun, the Moon, the planets and the stars - span around it. It was only about 500 to 600 years ago when astronomers were able to prove otherwise, and it finally became accepted that the Sun was at the center of the Solar System and that Earth orbited it.

                                             FACTS ABOUT EARTH

·    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.

·         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.

·         Earth is the densest planet in the solar system. The density of Earth differs in each part of the planet – the core, for example, is denser than the Earth’s crust – but the average density of the planet is around 5.52 grams per cubic centimeter.

·     The gravity between the Earth and the Moon causes the tides on Earth. This effect on the Moon means it is tidally locked to Earth – its rotation period is the same as its orbit time so it always presents the same face to Earth.

·   The Earth’s rotation is gradually slowing. This deceleration is happening almost imperceptibly, at approximately 17 milliseconds per hundred years, although the rate at which it occurs is not perfectly uniform. This has the effect of lengthening our days, but it happens so slowly that it could be as much as 140 million years before the length of a day will have increased to 25 hours.

·     The first life on Earth developed in the ocean through a process called a biogenesis . This is a natural process in which life grows from non-living matter like simple organic compounds.

·        Earth’s atmosphere is composed of 78% nitrogen, 21% oxygen, and trace amounts of other gases including argon and carbon dioxide.

·   The large amount of oxygen on Earth comes from our plant life’s consumption of carbon dioxide during photosynthesis.

·    Earth has relatively few visible impact craters compared with other solid bodies in our solar system. This is because Earth is geologically active and has processes like tectonics and erosion that reshape its surface.

·       Earth has a powerful magnetic field:This phenomenon is caused by the nickel-iron core of the planet, coupled with its rapid rotation. This field protects the Earth from the effects of solar wind

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·     The Earth has an Ozone Layer which protects it from harmful solar radiation. This shell is a special type of oxygen that absorbs most of the Sun’s powerful UV rays.

·         70% of the Earth’s surface is covered by water – the remainder consists of continents and islands which together have many lakes and other sources of water.

·         Earth’s water was initially trapped within the planet. Over time the Earth’s water was brought to the surface by the planet’s volcanic activity.

·         The highest point found on Earth is Mount Everest which reaches a height of 8.8 km.

·         The lowest point on Earth is called Challenger Deep and at 10.9 km below sea level, it is further than the peak of Mount Everest.

·         Earth has one of the most circular orbits of all the eight planets. Its axis of rotation is tilted 23.4° away from the perpendicular of its orbital plane, which produces the seasons we experience.

·          A year on Earth lasts just over 365 days.  It is actually 1/4 of a day over 365 days which is why we have a leap year every four years.

                                            SAVE MOTHER EARTH