14-1 Origin of the law of gravitation 1. In 16th century Copernicus(1473v 1543) proposed a heliocentric( sun-centered )scheme, in which the earth and other planets move about sun 2. Kepler(1571v1630) proposed three law which we discuss in Section 14-7) that describe Planet's motions However, Keplers Laws were only empirical without any basis in terms of forces14-1 Origin of the law of gravitation 1. In 16th century Copernicus ( 1473~1543 ) proposed a heliocentric ( sun-centered ) scheme, in which the Earth and other planets move about sun. 2. Kepler ( 1571~1630 ) proposed three law ( which we discuss in Section 14-7) that describe Planet’s motions. However, Kepler’s Laws were only empirical without any basis in terms of forces