Celestial Equator. Great circle of celestial sphere that is 90° from celestial poles. Is plane of Earth's equator carried to celestial concave. Usually called the Equinoctial.
Celestial Horizon. 'Rational horizon.'
Celestial Latitude. Angular distance above or below plane of Ecliptic. Measured on a circle of celestial longitude and prefixed with plus sign if north of Ecliptic, minus sign if south of it. Not usually considered in navigation.
Celestial Longitude. Angular distance along Ecliptic from First Point of Aries, measured in direction of Sun's apparent path and expressed in arc 0° to 360°. Not usually considered in navigation.
Share with your friends: |