Equinox Dates in 2018

ascension measures the horizontal position of the object in time units and the vernal equinox is taken as the reference point. Thus we can measure the position of the Sun at the equinoxes and solstices. In reference to the figure below, vernal equinox: RA= 0 hrs; declination= 0°. Summer solstice: RA= 6 hrs; declination= +23.5°. ................
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