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Astral Atlas
Wiki concept · Astronomy & coordinates

Geocentric

Measured from Earth’s center rather than from a particular observer on its surface.

In this entry

Word origin · etymology

Greek combining forms.

Geo- means earth and -centric means centered; the name specifies Earth as the positional origin.

Merriam-Webster: geocentric ↗

How we know · epistemology

Observer convention

Earth’s center is a mathematical observation origin. Geocentric positions are reproducible model outputs, but they omit the surface observer’s parallax and are not identical to every visible local direction.

Skyfield: astronomical positions ↗

Connected concepts

Terms used in this explanation

These links connect subjects and terminology. They do not establish a shared historical origin.

Sources & provenance

Use the citations beside each section to distinguish a calculation convention, a historical teaching and an editorial example.

Find these sources across the wiki →

  1. Skyfield: astronomical positions ↗
  2. Merriam-Webster: geocentric ↗