equatorial system
Quick Summary
The equatorial system is a celestial coordinate system used to pinpoint the position of objects in the sky. It is based on the celestial equator and poles, with coordinates analogous to terrestrial longitude and latitude. These coordinates are called right ascension and declination. Right ascension is measured eastward from the first point of Aries and is often expressed in hours, similar to a clock. Declination is analogous to latitude. Precise equatorial positions require specifying a particular year due to the continuous change caused by precession.123
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starBasic measurements…measured very accurately in the equatorial system (the coordinates of which are called right ascension [α, or RA] and declination [δ, or DEC] and are given for some epoch—for example, 1950.0 or, currently, 2000.0). Positions of fainter stars are measured by using electronic imaging devices (e.g., a charge-coupled device, or…
Read More…measured very accurately in the equatorial system (the coordinates of which are called right ascension [α, or RA] and declination [δ, or DEC] and are given for some epoch—for example, 1950.0 or, currently, 2000.0). Positions of fainter stars are measured by using electronic imaging devices (e.g., a charge-coupled device, or…
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astronomical mapThe equatorial systemBased on the celestial equator and poles, the equatorial coordinates, right ascension and declination, are directly analogous to terrestrial longitude and latitude. Right ascension, measured eastward from the first point of Aries (see directly above), is customarily divided into 24 hours rather than…
Read MoreBased on the celestial equator and poles, the equatorial coordinates, right ascension and declination, are directly analogous to terrestrial longitude and latitude. Right ascension, measured eastward from the first point of Aries (see directly above), is customarily divided into 24 hours rather than…
Read More