periapsis

Thân thiện

A satellite reaches its periapsis as it orbits the planet.

Definition

Noun (Astronomy): The point in the orbit of a celestial body or artificial satellite where it is nearest to the center of mass of the body it is orbiting.

Usage

This is a technical term used primarily in astronomy and orbital mechanics. It specifies the orbital position of minimum distance.

Examples: * The spacecraft fired its engines at periapsis to increase its orbital speed. * A planet's speed is greatest at the periapsis of its elliptical orbit. * Calculating the exact time of periapsis is crucial for mission planning.

Advanced Usage

• General vs. Specific Terms: "Periapsis" is the general term. When referring to a specific central body, more specific terms are used (e.g., perihelion for the Sun, perigee for Earth).
• Orbital Parameters: "Periapsis" is one of the standard orbital elements used to define the shape and orientation of an orbit, along with apoapsis (the farthest point).

Variants and Related Words

• Apoapsis (n): The point in an orbit farthest from the center of the body being orbited. (The opposite of periapsis).
• Peri-: A prefix meaning "near" or "around," used in compound terms like perihelion (closest to the Sun), perigee (closest to Earth), and perilune (closest to the Moon).

Synonyms

• Orbital pericenter: A more technical synonym.
• Pericenter: A shortened form of "orbital pericenter."

Antonyms

• Apoapsis: The point of greatest distance in an orbit.
• Apocenter / Apofocus: General terms for the farthest orbital point.

Học thuật

Noun

1. (astronomy) the point in an orbit closest to the body being orbited

Từ đồng nghĩa

• point of periapsis