Celestron 8i manual Right Ascension RA

	resolution.
Right Ascension: (RA)	the angular distance of a celestial object measured in hours, minutes, and seconds along
	the Celestial Equator eastward from the Vernal Equinox.
S -
Schmidt Telescope	Rated the most important advance in optics in 200 years, the Schmidt telescope combines
	the best features of the refractor and reflector for photographic purposes. It was invented in
	1930 by Bernhard Voldemar Schmidt (1879-1935).
Sidereal Rate	This is the angular speed at which the Earth is rotating. Telescope tracking motors drive
T -	the telescope at this rate. The rate is 15 arc seconds per second or 15 degrees per hour.
Terminator	The boundary line between the light and dark portion of the moon or a planet.
U -
Universe	The totality of astronomical things, events, relations and energies capable of being
V -	described objectively.
Variable Star	A star whose brightness varies over time due to either inherent properties of the star or
W -	something eclipsing or obscuring the brightness of the star.
Waning Moon	The period of the moon's cycle between full and new, when its illuminated portion is
	decreasing.
Waxing Moon	The period of the moon's cycle between new and full, when its illuminated portion is
Z -	increasing.
Zenith	The point on the Celestial Sphere directly above the observer.
Zodiac	The zodiac is the portion of the Celestial Sphere that lies within 8 deg on either side of the
	Ecliptic. The apparent paths of the Sun, the Moon, and the planets, with the exception of
	some portions of the path of Pluto, lie within this band. Twelve divisions, or signs, each 30
	deg in width, comprise the zodiac. These signs coincided with the zodiacal constellations
	about 2,000 years ago. Because of the Precession of the Earth's axis, the Vernal Equinox
	has moved westward by about 30 deg since that time; the signs have moved with it and
	thus no longer coincide with the constellations.

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