How many ice ages have there been? There have been five major ice ages through the history of our planet, but there have been several smaller ones as well. What is an ice age? An ice age is a period in time where the global temperature falls to the point where water freezes and ice […]
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What is a theodolite? A theodolite is a precision instrument used in surveying. Without it, people wouldn’t have known how tall our mountains were. Theodolites are still used for surveying today, but they have changed a lot to the earlier ones used. These days, theodolites are digital. The theodolite became common in surveying in the
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What is the albedo effect? The albedo effect is how much a surface is able to reflect sunlight. Light colored surfaces reflect more, and dark colored surfaces reflect more. The word “albedo” comes from the Latin word “albus”, which means “whiteness”. It is a way of measuring how much sunlight an object can reflect, and
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Why is the Mariana Trench so deep? The Mariana Trench is so deep because it has formed where the dense Pacific Plate has sunk underneath the less dense Philippine Sea Plate. The Mariana Trench is well known as the deepest point on Earth. Its deepest point is 10,984 meters. The pressure at that depth is
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Why is the border of Western Australia not straight? The border of Western Australia isn’t straight because they marked the border from the north and from the south at the same time and missed by 127 meters. If you zoom in on a Google map of Australia and look at the point where the borders
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Why were India, Pakistan, and Bangladesh split? India, Pakistan, and Bangladesh were split at the end of British rule in 1947, and they were split along religious grounds. Although, it was not a simple process and it has caused numerous problems. India became a colony of Britain in 1857. Queen Victoria I was proclaimed Empress
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What is the Anthropocene? The Anthropocene is the geologic age that we are in at the moment, although it is not agreed upon by experts. Geologic periods are a way of dividing the Earth up into chunks that cover different stages in the life of the Earth. It is a little like breaking a human
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When was the first world map made? The first world map was made in the 6th century BC, but it was very limited. The first map that is close to a modern map, i.e. having all of the continents on it, was probably made in the late 19th century. The problem with maps is that
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When was the compass invented? The compass was invented in China in the 4th century BC. However, it wasn’t used for navigation until over a thousand years later, also in China. A compass works because our planet has a magnetic field. The magnetic field is generated by the spinning ball of iron at the center
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What caused the US dust bowl? The dust bowl was caused by a combination of factors including bad farming practices, drought, high winds, and the economy. The dust bowl was named in 1935 by a reporter called Robert Geiger, but it was a phenomenon that had started in 1930, with causes going back long before
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