Johannes Kepler Research Paper

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Johannes Kepler was a mathematician, astronomer, and an astrologer from Germany. He was born on December 27, 1571 in Weil der Stadt, Germany and later died on November 15, 1630 in Regensburg, Germany.
Kepler has been an influential and important character in history. He introduced various ideas, unknown at the times. For example, in his time, people believed in a geocentric solar system―that planets and sun orbited around the earth in circular paths. Kepler disagreed, instead in a heliocentric model ―that the planets orbited the sun. This belief is represented by his first law. Kepler’s first law is the law of ellipses. It says that “planets move in ellipses with the sun at one focus.” (NASA). This means that the planets move in ellipses
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Kepler’s second law states, “As the planet moves along its path, a line joining the planet to the Sun sweeps out equal areas in equal times.” (plus.math). Due to the planets orbiting in a elliptic motion and sun being one of the foci, not the center, this would mean that the speed of the planet would be faster as it got closer to the sun. As stated in the law, the ellipsis sector would have equal area, but since the radius shortens and lengthen between the horizontal and vertical radii, the lengths of the sector’s sides would also have to lengthen and shorten. Thus, as the planet traveled closer to the sun, one of the foci, the two lengths of the radii would shorten and so expand the arc distance, which would then keep a constant area. The arc distance is the distance the planet travels at one time. If it was to lengthen, the planet would then have to travel farther in the same amount of time, and so travel at an increasing speed nearing the sun to cover an equal amount of area in an amount of time. An alternate way of explaining it, is that the planets speed is directly proportional to the sun gravitational pull. So, the farther the planet is away from the sun, the less pull there is due to the suns gravitational pull, and so causes the planet to move slower. But as the planet begins to travel closer, the gravitational pull from the sun
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