What are declination and right ascension?
They are coordinates resembling latitude and longitude, but instead of giving the position of a location on Earth, they give a position on the sphere of the heavens, for instance, the position of a star. Declination- δ (delta–small Greek d) is like latitude, measured in degrees, but from the North Pole, not from the equator, so that the north pole of the heavens has declination 0°, the equator has 90° and the south pole has 180°. Right Ascension- α (alpha– small Greek a, or RA) is like longitude, and “meridian lines” of constant RA connect the north and south poles of the sky and are everywhere perpendicular to lines of constant declination. RA and longitude differ in two ways. First, while the zero meridian on Earth is the one passing Greenwich, England, the celestial meridian on which α = 0 is the one passing one of the two points where the ecliptic crosses the celestial equator, in this case, the “first point in Aries” or “vernal equinox.” And second, for historical re
