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Astral Atlas
Wiki concept · Astronomy & coordinates

Meridian transit

Also called meridian transits · upper transit · lower transit · upper culmination · lower culmination

A body’s crossing of the observer’s meridian, at upper or lower transit on opposite sides of the celestial pole; alignment does not imply visibility.

In this entry

Word origin · etymology

Latin-derived astronomical phrase.

Meridian comes from meridies, midday; transit means crossing. The phrase names passage across the observer's north–south celestial circle.

Merriam-Webster: meridian ↗Merriam-Webster: transit ↗

How we know · epistemology

Earth-rotation geometry

Both crossings can occur below the horizon, or above it for a circumpolar body. Upper transit need not be overhead or exactly coincide with maximum altitude.

Skyfield: Almanac Computation — meridian transits and polar conditions ↗

Connected concepts

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: Almanac Computation — meridian transits and polar conditions ↗
  2. Merriam-Webster: meridian ↗
  3. Merriam-Webster: transit ↗