Planetary orbits are elliptical
because gravitational interaction over time changes
the delicate balance of mass, velocity and distance from the star
which otherwise keeps planetary orbit circular.
For a very long time,
from Ptolemy to the age of Copernicus,
it was widely believed and accepted that planets
in our Solar System revolved in a perfectly circular path.
Because the circle was presumed
to be an ideal shape for planetary bodies to orbit.
But then in the seventeenth century
in his seminal book Astronomia Nova,
Johannes Kepler rebutted this very idea.
He put forth his own theory pertaining to planetary motion.
He theorized that planetary bodies orbit
in an elliptical path with the Sun sitting at one of the foci of that ellipse.
In this video we will try to understand
what makes these planetary orbits elliptical.
WHY Are Most CELESTIAL ORBITS ELLIPTICAL? WildAC 15 June 2018
WHY Are Most CELESTIAL ORBITS ELLIPTICAL? Video WildAC 15 June 2018
elliptical orbit USA
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