Word origin · etymology
Latin and Greek mathematical vocabulary.
Osculating comes from osculari, to kiss; a locally fitted orbit metaphorically kisses the actual trajectory. Apogee means far from Earth.
How we know · epistemology
Instantaneous fitted-orbit geometry
An ellipse fitted to the current lunar state supplies this apogee. Perturbations continually change that fit, so its direction is not necessarily the place of the Moon's next actual greatest distance from Earth.
Connected concepts
Terms used in this explanation
These links connect subjects and terminology. They do not establish a shared historical origin.
Sources & provenance
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