The Universe is all of time and space and its contents. It includes planets, moons, minor planets, stars, galaxies, the contents of intergalactic space, and all matter and energy. The observable universe is about 91 billion light-years in diameter. The size of the entire Universe is unknown.
The word universe derives from the Old French word univers, which in turn derives from the Latin word universum.
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What is a leap Year?It takes the Earth 365 days and six hours to orbit around the Sun. The Six extra hours cannot be counted on the calander. So, to keep an accurate count, an extra day is added at the end of february every four years.
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What are the most precious stones?When the magma cools, the material which it contains solidifies in the form of crystals. Precious stones are crystals with particular characteristics of colour, hardness and the way they can reflect the light. They are used in making jewellery.
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How is the height of a mountain measured?To measure the height of mountain, the surface of the sea is taken as the point of reference. The height of the mountain is the distance between the top of the mountain and the surface of the sea.
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What is an electric current?An electric current is a passage of electrons from one electrified body to another which is less charged. When too many electrons are generated, they can move.
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Why does iron go rusty?Rust forms on the surface of iron objects when they are exposed to the air. It is the product of a chemical reaction called oxidization. The more the object is exposed to the air, the more rapidly rust spreads.
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How fast can a dog run?A Greyhound can run at a speed of 64km per hour, a Weimaraner , once used for hunting wolves and wild boar, can reach speed of up to 56 km per hour in a chase. Many breeds of dog which were once bred for hunting are now more common as pets than hunting Dogs.