How did Galileo realize that the Earth orbits the sun? He realized it when he observed the orbit of Venus. Galileo was born in 1564 in Pisa, Italy. Galileo is famous for saying that the Earth orbits the sun rather than the sun orbits the Earth, but he was not the first person to come […]
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How was the Great Pyramid at Giza built? There are several theories, but no one knows for definite. The Great Pyramid of Giza is the largest of the three pyramids in Giza and it was the first to be built. It was the oldest of the original seven wonders of the world and the only
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When was the first subway built? The first subway was the Metropolitan Railway line in London, opened on January 10, 1863. The city of London mostly sprung up when the Romans settled it in about 43 AD. They made their capital city in Colchester (Camulodunum), and London (Londinium) was a convenient place for them to
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When were glasses invented? The first wearable glasses were invented in Italy in the 13th century, but the Romans were using spheres of glass for magnification thirteen hundred years earlier. There are two types of eye problem that require correction with glasses. These are myopia (near-sightedness) and hyperopia (far-sightedness). When you are myopic, the light from
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Why do we say “born to the purple”? What is Tyrian purple? We say that someone who is born into a royal or powerful family is “born to the purple” because Tyrian purple was an incredibly expensive color that only wealthy and powerful people could afford. The dye for Tyrian purple was made from the
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When did people start using glass for windows? The Romans were the first people to have glass in their windows, but it wasn’t a common practice to have glass windows until the 17th century. There have been window holes since there have been houses because it is necessary to let the light in during the day.
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When were sunglasses invented? The first sunglasses were used by the Inuit people tens of thousands of years ago. The Inuit people lived, and still live, on the Arctic regions of Greenland, Canada, and Alaska. Snow blindness is a problem that they have always had to deal with. Snow blindness is not caused by the
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What were the moa and what happened to them? The South Island Giant Moa was a 3.6 m tall bird that were hunted to extinction by 1445. The Moa were flightless birds that lived in New Zealand. They were very similar to ostriches, but about a meter taller. When they stretched their necks up, the
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Why is oil measured in barrels? Oil is measured in barrels because that was the size of a wine barrel in 1866. Nobody really knows when barrels were invented, but there is a picture of a wooden barrel made to measure wheat on the wall of the tomb of the Egyptian high official, Hesy-Ra, from about
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Why is Christmas on December 25th? No one really knows, but there are several theories. Christmas is the day to celebrate the birth of Christ in a lot of the world. It is traditionally celebrated on December 25th, but there is no actual evidence for this date. The only accounts for the birth of Jesus
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