Definition of "pericenter" []

• The periapsis, the point of closest approach of an astronomical object in an elliptical orbit to its center of attraction. (noun)

Wiktionary.org : Text is available under the Creative Commons Attribution-ShareAlike License

• "A star called S2 (star) follows an elliptical orbit with a period of 15.2 years and a pericenter (closest) distance of 17 light hours from the central object."