Periapsis
ApoapsisPeriapsis
The smallest radial distance of an ellipse as measured from a focus. Taking v=0 in the equation of an ellipse
gives the periapsis distance
| r_-=a(1-e). |
Periapsis for an orbit around the Earth is called perigee, and periapsis for an orbit around the Sun is called perihelion.
See also
Apoapsis, Eccentricity, Ellipse, FocusExplore with Wolfram|Alpha
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Cite this as:
Weisstein, Eric W. "Periapsis." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/Periapsis.html