who first figured out the size of the earth?
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Eratosthenes Eratosthenes of Cyrene was a Greek mathematician, geographer, poet, astronomer, and music theorist. He was a man of learning, becoming the chief librarian at the Library of Alexandria. He invented the discipline of geography, including the terminology used today. He is best known for being the first person to calculate the circumference of the Earth, which he did by comparing altitudes of the mid-day sun at two places a known North-South distance apart. His calculation was remarkably accurate. H
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Busting a myth about Columbus and a flat Earth As early as the sixth century B.C., Pythagoras — and later Aristotle and Euclid — wrote about the Earth as a sphere. Ptolemy wrote “Geography” at the height of the Roman Empire, 1,300 years before Columbus sailed, and considered the idea of a round planet as fact.
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Flat Earth Belief in a flat Earth continued into the 5th century BC. Anaxagoras (c. 450 BC) agreed that the Earth was flat, and his pupil Archelaus believed that the flat Earth was depressed in the middle like a saucer, to allow for the fact that the Sun does not rise and set at the same time for everyone.
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- seismic waves and the layers of the earth Three hundred years ago the famous scientist Isaac Newton calculated, from his studies of planets and the force of gravity, that the average density of the Earth is twice that of surface rocks and therefore that the Earth's interior must be composed of much denser material.
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- Nicolaus  Copernicus, a Polish mathematician and astronomer, is the man who  realized that all the planets orbit around the sun. He got most of  that thought from the fact that the ancient Greeks discovered that  the Earth was round.
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Who Was Eratosthenes? The circumference of the Earth around the poles is now measured at around 40,008 km. Eratosthenes result is not bad at all. Very interesting is that the measurement of the distance between Alexandria and Syene is based on the estimated average speed of a caravan of camels that traveled this distance(!).
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Pangaea The concept that the continents once formed a continuous land mass was first proposed by Alfred Wegener, the originator of the theory of continental drift, in his 1912 publication The Origin of Continents (Die Entstehung der Kontinente).
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Age of the Earth In 1862, the physicist Lord Kelvin published calculations that fixed the age of Earth at between 20 million and 400 million years. He assumed that Earth had formed as a completely molten object, and determined the amount of time it would take for the near-surface to cool to its present temperature.
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- join brainly today. _______ was the first person to propose the idea of moving continents as a scientific hypothesis. A. Alfred Wegener B. Antonio Snider-Pelligrini C. Abraham Ortelius D. Charles Richter.
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Who discovered that the Earth moves around the Sun? The first person to do so ever was as early as the 3rd century BC by Aristarchus of Samos. Unfortunately, his notion gained only few supporters and was summarily rejected. Later in the 16th century, Nicholas Copernicus presented a mathematical model. In the next century, Johannes Kepler made inclusions of elliptical orbits, and Galileo Galilei presented supporting observations made using a telescope.
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How Science Figured Out the Age of Earth Editor’s note: The following is the introduction to a special e-publication called Determining the Age of the Earth (click the link to see a table of contents). Published earlier this year, the collection draws articles from the archives of Scientific American. Aristotle thought the earth had existed eternally.
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Flat Earth Several pre-Socratic philosophers believed that the world was flat: Thales (c. 550 BC) according to several sources, and Leucippus (c. 440 BC) and Democritus (c. 460 – 370 BC) according to Aristotle. Thales thought the earth floated in water like a log.
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Eratosthenes Finds Diameter of Earth! He found that at the same time, in Alexandria, Egypt, approximately 787 km due north of Syene (now Aswan), the angle of inclination of the sun s rays was about 7.2. With these measurements he computed the diameter and circumference of the earth as we will do.
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Eratosthenes' Calculation of Earth's Circumference The actual polar circumference of Earth is just a bit over 40 thousand km (about 24,860 miles). Eratosthenes was a talented mathematician and geographer as well as an astronomer. He made several other important contributions to science.
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"Fake ""History"" That Is Flatly Wrong" The writers of Prentice Hall Earth Science say, on page 213: For thousands of years, most people thought that the earth was flat. But as early as 300 B.C., the ancient Greeks theorized that the earth was round. Yet they still drew maps of a flat earth. As people explored more of the world, they were able to map large areas of it. In 150 A.D., the famous Greek astronomer Ptolemy made maps that included Europe, Africa, and most of Asia.
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Excerpt: 'Who Was First?' Like most educated people at the time, Columbus believed that the Earth was round—not flat, as some ignorant folks still insisted. The Ocean Sea was seen as a great expanse of water surrounding the land mass of Eurasia and Africa, which stretched from Europe in the west to China and Japan in the far distant east.
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Measuring the Size of Earth 1 The Earth is too big. 2  To measure the size of the Earth accurately, this can be done with the help of mathematics. 3  One way of doing it is to look at a star from two places on Earth. 4  If the distance is known between these two places, we can get answers to how big the Earth really is.
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Who discovered that the Earth moves around the Sun? The first person known to have proposed a heliocentric system, however, was Aristarchus of Samos (c. 270 BC). Like Eratosthenes, Aristarchus calculated the size of the Earth, and measured the size and distance of the Moon and Sun, in a treatise which has survived.
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Galaxy The first project to describe the shape of the Milky Way and the position of the Sun was undertaken by William Herschel in 1785 by counting the number of stars in different regions of the sky. He produced a diagram of the shape of the galaxy with the Solar System close to the center.
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Eratosthenes' Calculation of Earth's Circumference By noting the angles of shadows in two cities on the Summer Solstice, and by performing the right calculations using his knowledge of geometry and the distance between the cities, Eratosthenes was able to make a remarkably accurate calculation of the circumference of Earth.
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Who proved the Earth is round? Eratosthenes, calculated the Earth's radius around 1700 BC.He used the distance between two cities and the angle of the sun's rays made at midsummer at noon. His measurement turned out to be 15 percent too large, but still impressive, considering it was done over 2600 years ago.
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Flat Earth Several pre-Socratic philosophers believed that the world was flat: Thales (c. 550 BC) according to several sources, and Leucippus (c. 440 BC) and Democritus (c. 460 – 370 BC) according to Aristotle. Thales thought the earth floated in water like a log. It has been argued, however, that Thales actually believed in a round Earth.
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Hipparchus Hipparchus of Nicaea (/hɪˈpɑːrkəs/; Greek: ἵππαρχος, Hipparkhos; c. 190 – c. 120 BC) was a Greek astronomer, geographer, and mathematician. He is considered the founder of trigonometry but is most famous for his incidental discovery of precession of the equinoxes.
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(8) The Round Earth and Christopher Columbus if of the more recent measurements of the Earth, the one which makes the Earth smallest in circumference be introduced--I mean that of Posidonius who estimates its circumference at about 180,000 stadia, then.
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Approximations of Ï Archimedes, in his Measurement of a Circle, created the first algorithm for the calculation of π based on the idea that the perimeter of any (convex) polygon inscribed in a circle is less than the circumference of the circle, which, in turn, is less than the perimeter of any circumscribed polygon.
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Measuring the Size of an Earthquake The Richter Scale. Although similar seismographs had existed since the 1890's, it was only in 1935 that Charles F. Richter, a seismologist at the California Institute of Technology, introduced the concept of earthquake magnitude.