periapses

/ˌpɛriˈæpsiːz/
noun
  1. The points in an orbit around a celestial body (such as a planet or star) where the orbiting object is closest to that body.
    • Astronomers calculate the periapses of comets to predict how bright they will appear from Earth.
    • The spacecraft will study the planet's atmosphere during its periapses, when it flies closest to the surface.
    • Adjusting the orbit's periapses allows satellites to gather better data about the moon's gravity.
Antonyms
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