จุดปลายระยะทางวงโคจร

Also known as apsides, apse

lang=zxx|thumb|345px|The apsides refer to the farthest (2) and nearest (3) points reached by an orbiting planetary-mass object|planetary body (2 and 3) with respect to a primary, or host, body (1) An apsis ( (third declension); ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values.