The laws of orbital motion are mathematical, and one cannot explore them without some mathematics. ... Straight line : . ... The distance of the line from the origin thus fluctuates between a(1 - e) and a(1 + e) , and the result is a flattened circle or ellipse ; the point O (the origin) is its focus . ... We can now state Kepler's law more precisely as "the square of the orbital period T is proportional to the cube of the semi-major axis of its orbit around the Sun." ... Kepler's first law was: . ...

... 9a. Earth orbits Sun? . ... Kepler's Laws . ... and First Law . ... Such " polar coordinates " ( drawing on the left, below) are the ones best suited for describing planetary motion. ... All planetary orbits resemble ellipses, each with its own value of e or eccentricity : the smaller e is, the closer the shape to a circle. ... We can now state Kepler's law more precisely as "the square of the orbital period T is proportional to the cube of the semi-major axis a of its orbit around the Sun." ...

Jupiter is the largest of the nine planets, more than 10 times the diameter of Earth and more than 300 times its mass. ... The mean density of Earth is 5.245 times that of water. The pull of gravity on Jupiter at the top of the clouds at the equator is 2.4 times as great as gravity's pull at the surface of Earth at the equator. ... It is tipped about 11њ to Jupiter's axis of rotation, similar to Earth's, but it is also offset from the center of Jupiter by about 10,000 kilometers (6,200 miles). ...