![]() ![]() An example is the case of a satellite revolving around Earth. ![]() It is assumed that the gravitational effect of the lighter object on the heavier one is negligible. The laws are applicable whenever a comparatively light object revolves around a much heavier one because of gravitational attraction. From this one can show that the larger the orbit is, the slower the average speed of the orbiting object will be. The larger the distance from the Planet to the Sun, a, the longer the sidereal period. During this day, an imaginary line from the Sun to the planet will sweep out an area. Suppose a planet takes 1 day to travel from point A to B. This is also known as the law of equal areas. A planet moves most slowly when it is farthest from the Sun, or at aphelion. As a planet travels in its elliptical orbit, its distance, from the Sun, and speed vary.Ī planet moves most rapidly when it is nearest the Sun, or at perihelion. The semimajor axis, a, of an orbit is the average distance between the planet and the Sun. There is no object at the other focus of a planet’s orbit. ![]() Kepler’s Third Law (1618): The square of the sidereal period of a planet is directly proportional to the cube of the semimajor axis of the orbit. Kepler’s Second Law (1609): A line joining a planet and the Sun sweeps out equal areas in equal intervals of times. Kepler’s First Law (1609): The orbit of a planet about the Sun is an ellipse with the Sun at one focus. Isaac Newton was later able to derive the laws from his laws of motion and gravity, thereby producing strong evidence in favor of Newton’s inverse-square gravitational law. He found the first two laws in 1609 and the third one in 1618. Kepler found these laws empirically by studying extensive observations recorded by Tycho Brahe. Kepler’s Laws of Planetary Motion - The astronomer Johannes Kepler’s main contribution to astronomy was his three laws of planetary motion. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |