Applied Physics Research; Vol. 11, No. 2; 2019 ISSN 1916-9639 E-ISSN 1916-9647 Published by Canadian Center of Science and Education Newton’s Parabola Observed from Pappus’ Directrix, Apollonius’ Pedal Curve (Line), Newton’s Evolute, Leibniz’s Subtangent and Subnormal, Castillon’s Cardioid, and Ptolemy’s Circle (Hodograph) (09.02.2019) Jiří Stávek1 1 Bazovského, Prague, Czech Republic Correspondence: Jiří Stávek, Bazovského 1228, 163 00 Prague, Czech Republic. E-mail:
[email protected] Received: February 2, 2019 Accepted: February 20, 2019 Online Published: February 25, 2019 doi:10.5539/apr.v11n2p30 URL: http://dx.doi.org/10.5539/apr.v11n2p30 Abstract Johannes Kepler and Isaac Newton inspired generations of researchers to study properties of elliptic, hyperbolic, and parabolic paths of planets and other astronomical objects orbiting around the Sun. The books of these two Old Masters “Astronomia Nova” and “Principia…” were originally written in the geometrical language. However, the following generations of researchers translated the geometrical language of these Old Masters into the infinitesimal calculus independently discovered by Newton and Leibniz. In our attempt we will try to return back to the original geometrical language and to present several figures with possible hidden properties of parabolic orbits. For the description of events on parabolic orbits we will employ the interplay of the directrix of parabola discovered by Pappus of Alexandria, the pedal curve with the pedal point in the focus discovered by Apollonius of Perga (The Great Geometer), and the focus occupied by our Sun discovered in several stages by Aristarchus, Copernicus, Kepler and Isaac Newton (The Great Mathematician).