`implies` Law of Orbits :
`implies` All planets move in elliptical orbits with the sun situated at one of the foci of the ellipse.
`implies` An ellipse traced out by a planet around the sun. The closest point is P and farthest point is A. P is called the Perihelion and A the aphelion. The semi major axis is half the distance AP.
`implies` This law was a deviation from the Copernican model which allowed only circular orbits. (The ellipse of which the circle is a special case is a closed curve).
